release 17.03-beta

2026-06-13 16:53:53 +00:00 · 2017-02-27 20:12:01 +01:00
12006 changed files with 340860 additions and 485274 deletions
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -1,93 +0,0 @@
-# CODEOWNERS file
-#
-# This file is used to describe who owns what in this repository. This file does not
-# replace `meta.maintainers` but is instead used for other things than derivations
-# and modules, like documentation, package sets, and other assets.
-#
-# For documentation on this file, see https://help.github.com/articles/about-codeowners/
-# Mentioned users will get code review requests.
-
-# This file
-/.github/CODEOWNERS @edolstra
-
-# Libraries
-/lib                        @edolstra @nbp
-/lib/systems                @nbp @ericson2314
-
-# Nixpkgs Internals
-/default.nix                          @nbp
-/pkgs/top-level/default.nix           @nbp @Ericson2314
-/pkgs/top-level/impure.nix            @nbp @Ericson2314
-/pkgs/top-level/stage.nix             @nbp @Ericson2314
-/pkgs/stdenv
-/pkgs/build-support/cc-wrapper        @Ericson2314 @orivej
-/pkgs/build-support/bintools-wrapper  @Ericson2314 @orivej
-/pkgs/build-support/setup-hooks       @Ericson2314
-
-# NixOS Internals
-/nixos/default.nix          @nbp
-/nixos/lib/from-env.nix     @nbp
-/nixos/lib/eval-config.nix  @nbp
-/nixos/doc/manual/configuration/abstractions.xml      @nbp
-/nixos/doc/manual/configuration/config-file.xml       @nbp
-/nixos/doc/manual/configuration/config-syntax.xml     @nbp
-/nixos/doc/manual/configuration/modularity.xml        @nbp
-/nixos/doc/manual/development/assertions.xml          @nbp
-/nixos/doc/manual/development/meta-attributes.xml     @nbp
-/nixos/doc/manual/development/option-declarations.xml @nbp
-/nixos/doc/manual/development/option-def.xml          @nbp
-/nixos/doc/manual/development/option-types.xml        @nbp
-/nixos/doc/manual/development/replace-modules.xml     @nbp
-/nixos/doc/manual/development/writing-modules.xml     @nbp
-/nixos/doc/manual/man-nixos-option.xml                @nbp
-/nixos/modules/installer/tools/nixos-option.sh        @nbp
-
-# Python-related code and docs
-/pkgs/top-level/python-packages.nix     @FRidh
-/pkgs/development/interpreters/python   @FRidh
-/pkgs/development/python-modules        @FRidh
-/doc/languages-frameworks/python.md     @FRidh
-
-# Haskell
-/pkgs/development/compilers/ghc                       @peti
-/pkgs/development/haskell-modules                     @peti
-/pkgs/development/haskell-modules/default.nix         @peti
-/pkgs/development/haskell-modules/generic-builder.nix @peti
-/pkgs/development/haskell-modules/hoogle.nix          @peti
-
-# R
-/pkgs/applications/science/math/R   @peti
-/pkgs/development/r-modules         @peti
-
-# Ruby
-/pkgs/development/interpreters/ruby @zimbatm
-/pkgs/development/ruby-modules      @zimbatm
-
-# Darwin-related
-/pkgs/stdenv/darwin         @NixOS/darwin-maintainers
-/pkgs/os-specific/darwin    @NixOS/darwin-maintainers
-
-# Beam-related (Erlang, Elixir, LFE, etc)
-/pkgs/development/beam-modules                  @gleber
-/pkgs/development/interpreters/erlang           @gleber
-/pkgs/development/interpreters/lfe              @gleber
-/pkgs/development/interpreters/elixir           @gleber
-/pkgs/development/tools/build-managers/rebar    @gleber
-/pkgs/development/tools/build-managers/rebar3   @gleber
-/pkgs/development/tools/erlang                  @gleber
-
-# Jetbrains
-/pkgs/applications/editors/jetbrains @edwtjo
-
-# Eclipse
-/pkgs/applications/editors/eclipse @rycee
-
-# https://github.com/NixOS/nixpkgs/issues/31401
-/lib/maintainers.nix @ghost
-/lib/licenses.nix @ghost
-
-# Qt / KDE
-/pkgs/applications/kde @ttuegel
-/pkgs/desktops/plasma-5 @ttuegel
-/pkgs/development/libraries/kde-frameworks @ttuegel
-/pkgs/development/libraries/qt-5 @ttuegel
--- a/.github/CONTRIBUTING.md
+++ b/.github/CONTRIBUTING.md
@@ -12,34 +12,31 @@ under the terms of [COPYING](../COPYING), which is an MIT-like license.

 ## Submitting changes

-* Format the commit messages in the following way:
+* Format the commits in the following way:

  ```
-  (pkg-name | nixos/<module>): (from -> to | init at version | refactor | etc)
-
+  (pkg-name | service-name): (from -> to | init at version | refactor | etc)
+  
  (Motivation for change. Additional information.)
  ```

  Examples:

  * nginx: init at 2.0.1
-  * firefox: 54.0.1 -> 55.0
-  * nixos/hydra: add bazBaz option
-
+  * firefox: 3.0 -> 3.1.1
+  * hydra service: add bazBaz option
+  
    Dual baz behavior is needed to do foo.
-  * nixos/nginx: refactor config generation
-
+  * nginx service: refactor config generation
+    
    The old config generation system used impure shell scripts and could break in specific circumstances (see #1234).

 * `meta.description` should:
-  * Be capitalized.
-  * Not start with the package name.
-  * Not have a period at the end.
-* `meta.license` must be set and fit the upstream license.
-  * If there is no upstream license, `meta.license` should default to `stdenv.lib.licenses.unfree`.
-* `meta.maintainers` must be set.
+  * Be capitalized
+  * Not start with the package name
+  * Not have a dot at the end

-See the nixpkgs manual for more details on [standard meta-attributes](https://nixos.org/nixpkgs/manual/#sec-standard-meta-attributes) and on how to [submit changes to nixpkgs](https://nixos.org/nixpkgs/manual/#chap-submitting-changes).
+See the nixpkgs manual for more details on how to [Submit changes to nixpkgs](https://nixos.org/nixpkgs/manual/#chap-submitting-changes).

 ## Writing good commit messages

--- a/.github/ISSUE_TEMPLATE.md
+++ b/.github/ISSUE_TEMPLATE.md
@@ -8,5 +8,6 @@

 ## Technical details

-Please run `nix-shell -p nix-info --run "nix-info -m"` and paste the
-results.
+* System: (NixOS: `nixos-version`, Ubuntu/Fedora: `lsb_release -a`, ...)
+* Nix version: (run `nix-env --version`)
+* Nixpkgs version: (run `nix-instantiate --eval '<nixpkgs>' -A lib.nixpkgsVersion`)
--- a/.github/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -3,14 +3,14 @@

 ###### Things done

-<!-- Please check what applies. Note that these are not hard requirements but merely serve as information for reviewers. -->
-
- [ ] Tested using sandboxing ([nix.useSandbox](http://nixos.org/nixos/manual/options.html#opt-nix.useSandbox) on NixOS, or option `build-use-sandbox` in [`nix.conf`](http://nixos.org/nix/manual/#sec-conf-file) on non-NixOS)
+- [ ] Tested using sandboxing
+  ([nix.useSandbox](http://nixos.org/nixos/manual/options.html#opt-nix.useSandbox) on NixOS,
+    or option `build-use-sandbox` in [`nix.conf`](http://nixos.org/nix/manual/#sec-conf-file)
+    on non-NixOS)
 - Built on platform(s)
   - [ ] NixOS
   - [ ] macOS
-   - [ ] other Linux distributions
- [ ] Tested via one or more NixOS test(s) if existing and applicable for the change (look inside [nixos/tests](https://github.com/NixOS/nixpkgs/blob/master/nixos/tests))
+   - [ ] Linux
 - [ ] Tested compilation of all pkgs that depend on this change using `nix-shell -p nox --run "nox-review wip"`
 - [ ] Tested execution of all binary files (usually in `./result/bin/`)
 - [ ] Fits [CONTRIBUTING.md](https://github.com/NixOS/nixpkgs/blob/master/.github/CONTRIBUTING.md).
--- a/.mention-bot
+++ b/.mention-bot
@@ -0,0 +1,13 @@
+{
+  "userBlacklist": [
+    "civodul",
+    "jhasse",
+    "shlevy"
+  ],
+  "alwaysNotifyForPaths": [
+    { "name": "FRidh", "files": ["pkgs/top-level/python-packages.nix", "pkgs/development/interpreters/python/*", "pkgs/development/python-modules/*" ] },
+    { "name": "LnL7", "files": ["pkgs/stdenv/darwin/*", "pkgs/os-specific/darwin/*"] },
+    { "name": "copumpkin", "files": ["pkgs/stdenv/darwin/*", "pkgs/os-specific/darwin/apple-source-releases/*"] }
+  ],
+  "fileBlacklist": ["pkgs/top-level/all-packages.nix"]
+}
--- a/.travis.yml
+++ b/.travis.yml
@@ -0,0 +1,20 @@
+language: nix
+matrix:
+    include:
+        - os: linux
+          sudo: false
+          script:
+              - ./maintainers/scripts/travis-nox-review-pr.sh nixpkgs-verify nixpkgs-manual nixpkgs-tarball nixpkgs-unstable
+              - ./maintainers/scripts/travis-nox-review-pr.sh nixos-options nixos-manual
+        - os: linux
+          sudo: required
+          dist: trusty
+          before_script:
+              - sudo mount -o remount,exec,size=2G,mode=755 /run/user
+          script: ./maintainers/scripts/travis-nox-review-pr.sh nox pr
+        - os: osx
+          osx_image: xcode7.3
+          script: ./maintainers/scripts/travis-nox-review-pr.sh nox pr
+env:
+    global:
+        - GITHUB_TOKEN=5edaaf1017f691ed34e7f80878f8f5fbd071603f
--- a/.version
+++ b/.version
@@ -1 +1 @@
-18.03
+17.03
--- a/6
+++ b/6
@@ -1,4 +1,4 @@
-Copyright (c) 2003-2018 Eelco Dolstra and the Nixpkgs/NixOS contributors
+Copyright (c) 2003-2017 Eelco Dolstra and the Nixpkgs/NixOS contributors

 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
@@ -23,7 +23,9 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

 Note: the license above does not apply to the packages built by the
 Nix Packages collection, merely to the package descriptions (i.e., Nix
-expressions, build scripts, etc.).  It also might not apply to patches
+expressions, build scripts, etc.).  Also, the license does not apply
+to some of the binaries used for bootstrapping Nixpkgs (e.g.,
+pkgs/stdenv/linux/tools/bash).  It also might not apply to patches
 included in Nixpkgs, which may be derivative works of the packages to
 which they apply.  The aforementioned artifacts are all covered by the
 licenses of the respective packages.
--- a/README.md
+++ b/README.md
@@ -1,9 +1,10 @@
-[<img src="https://nixos.org/logo/nixos-hires.png" width="500px" alt="logo" />](https://nixos.org/nixos)
+[<img src="http://nixos.org/logo/nixos-hires.png" width="500px" alt="logo" />](https://nixos.org/nixos)

+[![Build Status](https://travis-ci.org/NixOS/nixpkgs.svg?branch=master)](https://travis-ci.org/NixOS/nixpkgs)
 [![Code Triagers Badge](https://www.codetriage.com/nixos/nixpkgs/badges/users.svg)](https://www.codetriage.com/nixos/nixpkgs)

 Nixpkgs is a collection of packages for the [Nix](https://nixos.org/nix/) package
-manager. It is periodically built and tested by the [Hydra](https://hydra.nixos.org/)
+manager. It is periodically built and tested by the [hydra](http://hydra.nixos.org/)
 build daemon as so-called channels. To get channel information via git, add
 [nixpkgs-channels](https://github.com/NixOS/nixpkgs-channels.git) as a remote:

@@ -12,30 +13,30 @@ build daemon as so-called channels. To get channel information via git, add
 ```

 For stability and maximum binary package support, it is recommended to maintain
-custom changes on top of one of the channels, e.g. `nixos-17.09` for the latest
+custom changes on top of one of the channels, e.g. `nixos-16.09` for the latest
 release and `nixos-unstable` for the latest successful build of master:

 ```
 % git remote update channels
-% git rebase channels/nixos-17.09
+% git rebase channels/nixos-16.09
 ```

 For pull-requests, please rebase onto nixpkgs `master`.

-[NixOS](https://nixos.org/nixos/) Linux distribution source code is located inside
+[NixOS](https://nixos.org/nixos/) linux distribution source code is located inside
 `nixos/` folder.

 * [NixOS installation instructions](https://nixos.org/nixos/manual/#ch-installation)
 * [Documentation (Nix Expression Language chapter)](https://nixos.org/nix/manual/#ch-expression-language)
 * [Manual (How to write packages for Nix)](https://nixos.org/nixpkgs/manual/)
 * [Manual (NixOS)](https://nixos.org/nixos/manual/)
-* [Community maintained wiki](https://nixos.wiki/)
+* [Nix Wiki](https://nixos.org/wiki/) (deprecated, see milestone ["Move the Wiki!"](https://github.com/NixOS/nixpkgs/issues?q=is%3Aopen+is%3Aissue+milestone%3A%22Move+the+wiki%21%22))
 * [Continuous package builds for unstable/master](https://hydra.nixos.org/jobset/nixos/trunk-combined)
-* [Continuous package builds for 17.09 release](https://hydra.nixos.org/jobset/nixos/release-17.09)
+* [Continuous package builds for 16.09 release](https://hydra.nixos.org/jobset/nixos/release-16.09)
 * [Tests for unstable/master](https://hydra.nixos.org/job/nixos/trunk-combined/tested#tabs-constituents)
-* [Tests for 17.09 release](https://hydra.nixos.org/job/nixos/release-17.09/tested#tabs-constituents)
+* [Tests for 16.09 release](https://hydra.nixos.org/job/nixos/release-16.09/tested#tabs-constituents)

 Communication:

-* [Mailing list](https://groups.google.com/forum/#!forum/nix-devel)
+* [Mailing list](http://lists.science.uu.nl/mailman/listinfo/nix-dev)
 * [IRC - #nixos on freenode.net](irc://irc.freenode.net/#nixos)
--- a/default.nix
+++ b/default.nix
@@ -2,17 +2,7 @@ let requiredVersion = import ./lib/minver.nix; in

 if ! builtins ? nixVersion || builtins.compareVersions requiredVersion builtins.nixVersion == 1 then

-  abort ''
-
-    This version of Nixpkgs requires Nix >= ${requiredVersion}, please upgrade:
-
-    - If you are running NixOS, use `nixos-rebuild' to upgrade your system.
-
-    - If you installed Nix using the install script (https://nixos.org/nix/install),
-      it is safe to upgrade by running it again:
-
-          curl https://nixos.org/nix/install | sh
-  ''
+  abort "This version of Nixpkgs requires Nix >= ${requiredVersion}, please upgrade! See https://nixos.org/wiki/How_to_update_when_Nix_is_too_old_to_evaluate_Nixpkgs"

 else

--- a/doc/.gitignore
+++ b/doc/.gitignore
@@ -1,6 +0,0 @@
-*.chapter.xml
-*.section.xml
-.version
-out
-manual-full.xml
-highlightjs
--- a/doc/Makefile
+++ b/doc/Makefile
@@ -1,96 +0,0 @@
-MD_TARGETS=$(addsuffix .xml, $(basename $(wildcard ./*.md ./**/*.md)))
-
-.PHONY: all
-all: validate out/html/index.html out/epub/manual.epub
-
-.PHONY: debug
-debug:
-	nix-shell --run "xmloscopy --docbook5 ./manual.xml ./manual-full.xml"
-
-.PHONY: clean
-clean:
-	rm -f ${MD_TARGETS} .version manual-full.xml
-	rm -rf ./out/ ./highlightjs
-
-.PHONY: validate
-validate: manual-full.xml
-	jing "$$RNG" manual-full.xml
-
-out/html/index.html: manual-full.xml style.css highlightjs
-	mkdir -p out/html
-	xsltproc ${xsltFlags} \
-		--nonet --xinclude \
-		--output $@ \
-		"$$XSL/docbook/xhtml/docbook.xsl" \
-		./manual-full.xml
-
-	mkdir -p out/html/highlightjs/
-	echo "document.onreadystatechange = function () { \
-	  var listings = document.querySelectorAll('.programlisting, .screen'); \
-	  for (i = 0; i < listings.length; ++i) { \
-	     hljs.highlightBlock(listings[i]); \
-	  } \
-	} " > out/html/highlightjs/loader.js
-
-	cp -r highlightjs out/html/
-
-	cp ./overrides.css out/html/
-	cp ./style.css out/html/style.css
-
-	mkdir -p out/html/images/callouts
-	cp "$$XSL/docbook/images/callouts/"*.svg out/html/images/callouts/
-	chmod u+w -R out/html/
-
-out/epub/manual.epub: manual-full.xml
-	mkdir -p out/epub/scratch
-	xsltproc ${xsltFlags} --nonet \
-		--output out/epub/scratch/ \
-		"$$XSL/docbook/epub/docbook.xsl" \
-		./manual-full.xml
-
-	cp ./overrides.css out/epub/scratch/OEBPS
-	cp ./style.css out/epub/scratch/OEBPS
-	mkdir -p out/epub/scratch/OEBPS/images/callouts/
-	cp "$$XSL/docbook/images/callouts/"*.svg out/epub/scratch/OEBPS/images/callouts/
-	echo "application/epub+zip" > mimetype
-	zip -0Xq "out/epub/manual.epub" mimetype
-	rm mimetype
-	cd "out/epub/scratch/" && zip -Xr9D "../manual.epub" *
-	rm -rf "out/epub/scratch/"
-
-highlightjs:
-	mkdir -p highlightjs
-	cp -r "$$HIGHLIGHTJS/highlight.pack.js" highlightjs/
-	cp -r "$$HIGHLIGHTJS/LICENSE" highlightjs/
-	cp -r "$$HIGHLIGHTJS/mono-blue.css" highlightjs/
-
-
-manual-full.xml: ${MD_TARGETS} .version *.xml
-	xmllint --nonet --xinclude --noxincludenode manual.xml --output manual-full.xml
-
-.version:
-	nix-instantiate --eval \
-		-E '(import ../lib).nixpkgsVersion' > .version
-
-%.section.xml: %.section.md
-	pandoc $^ -w docbook+smart \
-		-f markdown+smart \
-	  | sed -e 's|<ulink url=|<link xlink:href=|' \
-	      -e 's|</ulink>|</link>|' \
-	      -e 's|<sect. id=|<section xml:id=|' \
-	      -e 's|</sect[0-9]>|</section>|' \
-	      -e '1s| id=| xml:id=|' \
-	      -e '1s|\(<[^ ]* \)|\1xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" |' \
-	| cat  > $@
-
-%.chapter.xml: %.chapter.md
-	pandoc $^ -w docbook+smart \
-		--top-level-division=chapter \
-		-f markdown+smart \
-	  | sed -e 's|<ulink url=|<link xlink:href=|' \
-	      -e 's|</ulink>|</link>|' \
-	      -e 's|<sect. id=|<section xml:id=|' \
-	      -e 's|</sect[0-9]>|</section>|' \
-	      -e '1s| id=| xml:id=|' \
-	      -e '1s|\(<[^ ]* \)|\1|' \
-	| cat  > $@
--- a/doc/coding-conventions.xml
+++ b/doc/coding-conventions.xml
@@ -18,9 +18,9 @@
  tab settings so it’s asking for trouble.</para></listitem>

  <listitem><para>Use <literal>lowerCamelCase</literal> for variable
-  names, not <literal>UpperCamelCase</literal>.  Note, this rule does
-  not apply to package attribute names, which instead follow the rules
-  in <xref linkend="sec-package-naming"/>.</para></listitem>
+  names, not <literal>UpperCamelCase</literal>.  TODO: naming of
+  attributes in
+  <filename>all-packages.nix</filename>?</para></listitem>

  <listitem><para>Function calls with attribute set arguments are
  written as
@@ -220,10 +220,9 @@ args.stdenv.mkDerivation (args // {

  <listitem><para>The variable name used for the instantiated package
  in <filename>all-packages.nix</filename>, and when passing it as a
-  dependency to other functions.  Typically this is called the
-  <emphasis>package attribute name</emphasis>.  This is what Nix
-  expression authors see.  It can also be used when installing using
-  <command>nix-env -iA</command>.</para></listitem>
+  dependency to other functions.  This is what Nix expression authors
+  see.  It can also be used when installing using <command>nix-env
+  -iA</command>.</para></listitem>

  <listitem><para>The filename for (the directory containing) the Nix
  expression.</para></listitem>
@@ -255,17 +254,17 @@ bound to the variable name <varname>e2fsprogs</varname> in
  dash) — e.g., <literal>"hello-0.3.1rc2"</literal>.</para></listitem>

  <listitem><para>If a package is not a release but a commit from a repository, then
-  the version part of the name <emphasis>must</emphasis> be the date of that
+  the version part of the name <emphasis>must</emphasis> be the date of that 
  (fetched) commit. The date must be in <literal>"YYYY-MM-DD"</literal> format.
  Also append <literal>"unstable"</literal> to the name - e.g.,
  <literal>"pkgname-unstable-2014-09-23"</literal>.</para></listitem>

-  <listitem><para>Dashes in the package name should be preserved in
-  new variable names, rather than converted to underscores or camel
-  cased — e.g., <varname>http-parser</varname> instead of
-  <varname>http_parser</varname> or <varname>httpParser</varname>.  The
-  hyphenated style is preferred in all three package
-  names.</para></listitem>
+  <listitem><para>Dashes in the package name should be preserved
+  in new variable names, rather than converted to underscores
+  (which was convention up to around 2013 and most names
+   still have underscores instead of dashes) — e.g.,
+  <varname>http-parser</varname> instead of
+  <varname>http_parser</varname>.</para></listitem>

  <listitem><para>If there are multiple versions of a package, this
  should be reflected in the variable names in
@@ -366,7 +365,7 @@ splitting up an existing category.</para>
  <varlistentry>
    <term>If it’s a (set of) <emphasis>tool(s)</emphasis>:</term>
    <listitem>
-      <para>(A tool is a relatively small program, especially one intended
+      <para>(A tool is a relatively small program, especially one intented
      to be used non-interactively.)</para>
      <variablelist>
        <varlistentry>
@@ -457,7 +456,7 @@ splitting up an existing category.</para>
  <varlistentry>
    <term>If it’s a <emphasis>window manager</emphasis>:</term>
    <listitem>
-      <para><filename>applications/window-managers</filename> (e.g. <filename>awesome</filename>, <filename>stumpwm</filename>)</para>
+      <para><filename>applications/window-managers</filename> (e.g. <filename>awesome</filename>, <filename>compiz</filename>, <filename>stumpwm</filename>)</para>
    </listitem>
  </varlistentry>
  <varlistentry>
@@ -609,7 +608,7 @@ evaluate correctly.</para>
 </section>
 <section xml:id="sec-sources"><title>Fetching Sources</title>
  <para>There are multiple ways to fetch a package source in nixpkgs. The
-    general guideline is that you should package sources with a high degree of
+    general guidline is that you should package sources with a high degree of
    availability. Right now there is only one fetcher which has mirroring
    support and that is <literal>fetchurl</literal>. Note that you should also
    prefer protocols which have a corresponding proxy environment variable.
@@ -662,7 +661,9 @@ src = fetchFromGitHub {
 </section>

 <section xml:id="sec-patches"><title>Patches</title>
-  <para>Patches available online should be retrieved using
+  <para>Only patches that are unique to <literal>nixpkgs</literal> should be 
+    included in <literal>nixpkgs</literal> source.</para>
+  <para>Patches available online should be retrieved using 
    <literal>fetchpatch</literal>.</para>
  <para>
 <programlisting>
@@ -675,30 +676,5 @@ patches = [
 ];
 </programlisting>
  </para>
-  <para>Otherwise, you can add a <literal>.patch</literal> file to the
-  <literal>nixpkgs</literal> repository. In the interest of keeping our
-  maintenance burden to a minimum, only patches that are unique
-  to <literal>nixpkgs</literal> should be added in this way.</para>
-<para><programlisting>
-patches = [ ./0001-changes.patch ];
-</programlisting></para>
-  <para>If you do need to do create this sort of patch file,
-  one way to do so is with git:
-  <orderedlist>
-    <listitem><para>Move to the root directory of the source code
-    you're patching.<screen>
-$ cd the/program/source</screen></para></listitem>
-    <listitem><para>If a git repository is not already present,
-    create one and stage all of the source files.<screen>
-$ git init
-$ git add .</screen></para></listitem>
-    <listitem><para>Edit some files to make whatever changes need
-    to be included in the patch.</para></listitem>
-    <listitem><para>Use git to create a diff, and pipe the output
-    to a patch file:<screen>
-$ git diff > nixpkgs/pkgs/the/package/0001-changes.patch</screen>
-    </para></listitem>
-  </orderedlist></para>
 </section>
-
 </chapter>
--- a/doc/configuration.xml
+++ b/doc/configuration.xml
@@ -55,10 +55,6 @@ configuration file located at
 </programlisting>
 </para>

-<para>Note that we are not able to test or build unfree software on Hydra
-due to policy. Most unfree licenses prohibit us from either executing or
-distributing the software.</para>
-
 <section xml:id="sec-allow-broken">
  <title>Installing broken packages</title>

@@ -231,7 +227,7 @@ packages via <literal>packageOverrides</literal></title>

 <para>You can define a function called
 <varname>packageOverrides</varname> in your local
-<filename>~/.config/nixpkgs/config.nix</filename> to override nix packages.  It
+<filename>~/.config/nixpkgs/config.nix</filename> to overide nix packages.  It
 must be a function that takes pkgs as an argument and return modified
 set of packages.

@@ -247,218 +243,5 @@ set of packages.

 </section>

-<section xml:id="sec-declarative-package-management">
-  <title>Declarative Package Management</title>
-
-  <section xml:id="sec-building-environment">
-    <title>Build an environment</title>
-
-    <para>
-      Using <literal>packageOverrides</literal>, it is possible to manage
-      packages declaratively. This means that we can list all of our desired
-      packages within a declarative Nix expression. For example, to have
-      <literal>aspell</literal>, <literal>bc</literal>,
-      <literal>ffmpeg</literal>, <literal>coreutils</literal>,
-      <literal>gdb</literal>, <literal>nixUnstable</literal>,
-      <literal>emscripten</literal>, <literal>jq</literal>,
-      <literal>nox</literal>, and <literal>silver-searcher</literal>, we could
-      use the following in <filename>~/.config/nixpkgs/config.nix</filename>:
-    </para>
-
-    <screen>
-{
-  packageOverrides = pkgs: with pkgs; {
-    myPackages = pkgs.buildEnv {
-      name = "my-packages";
-      paths = [ aspell bc coreutils gdb ffmpeg nixUnstable emscripten jq nox silver-searcher ];
-    };
-  };
-}
-    </screen>
-
-    <para>
-      To install it into our environment, you can just run <literal>nix-env -iA
-      nixpkgs.myPackages</literal>. If you want to load the packages to be built
-      from a working copy of <literal>nixpkgs</literal> you just run
-      <literal>nix-env -f. -iA myPackages</literal>. To explore what's been
-      installed, just look through <filename>~/.nix-profile/</filename>. You can
-      see that a lot of stuff has been installed. Some of this stuff is useful
-      some of it isn't. Let's tell Nixpkgs to only link the stuff that we want:
-    </para>
-
-    <screen>
-{
-  packageOverrides = pkgs: with pkgs; {
-    myPackages = pkgs.buildEnv {
-      name = "my-packages";
-      paths = [ aspell bc coreutils gdb ffmpeg nixUnstable emscripten jq nox silver-searcher ];
-      pathsToLink = [ "/share" "/bin" ];
-    };
-  };
-}
-    </screen>
-
-    <para>
-      <literal>pathsToLink</literal> tells Nixpkgs to only link the paths listed
-      which gets rid of the extra stuff in the profile.
-      <filename>/bin</filename> and <filename>/share</filename> are good
-      defaults for a user environment, getting rid of the clutter. If you are
-      running on Nix on MacOS, you may want to add another path as well,
-      <filename>/Applications</filename>, that makes GUI apps available.
-    </para>
-
-  </section>
-
-  <section xml:id="sec-getting-documentation">
-    <title>Getting documentation</title>
-
-    <para>
-      After building that new environment, look through
-      <filename>~/.nix-profile</filename> to make sure everything is there that
-      we wanted. Discerning readers will note that some files are missing. Look
-      inside <filename>~/.nix-profile/share/man/man1/</filename> to verify this.
-      There are no man pages for any of the Nix tools! This is because some
-      packages like Nix have multiple outputs for things like documentation (see
-      section 4). Let's make Nix install those as well.
-    </para>
-
-    <screen>
-{
-  packageOverrides = pkgs: with pkgs; {
-    myPackages = pkgs.buildEnv {
-      name = "my-packages";
-      paths = [ aspell bc coreutils ffmpeg nixUnstable emscripten jq nox silver-searcher ];
-      pathsToLink = [ "/share/man" "/share/doc" /bin" ];
-      extraOutputsToInstall = [ "man" "doc" ];
-    };
-  };
-}
-    </screen>
-
-    <para>
-      This provides us with some useful documentation for using our packages.
-      However, if we actually want those manpages to be detected by man, we need
-      to set up our environment. This can also be managed within Nix
-      expressions.
-    </para>
-
-    <screen>
-{
-  packageOverrides = pkgs: with pkgs; rec {
-    myProfile = writeText "my-profile" ''
-export PATH=$HOME/.nix-profile/bin:/nix/var/nix/profiles/default/bin:/sbin:/bin:/usr/sbin:/usr/bin
-export MANPATH=$HOME/.nix-profile/share/man:/nix/var/nix/profiles/default/share/man:/usr/share/man
-    '';
-    myPackages = pkgs.buildEnv {
-      name = "my-packages";
-      paths = [
-        (runCommand "profile" {} ''
-mkdir -p $out/etc/profile.d
-cp ${myProfile} $out/etc/profile.d/my-profile.sh
-        '')
-        aspell
-        bc
-        coreutils
-        ffmpeg
-        man
-        nixUnstable
-        emscripten
-        jq
-        nox
-        silver-searcher
-      ];
-      pathsToLink = [ "/share/man" "/share/doc" /bin" "/etc" ];
-      extraOutputsToInstall = [ "man" "doc" ];
-    };
-  };
-}
-    </screen>
-
-    <para>
-      For this to work fully, you must also have this script sourced when you
-      are logged in. Try adding something like this to your
-      <filename>~/.profile</filename> file:
-    </para>
-
-    <screen>
-#!/bin/sh
-if [ -d $HOME/.nix-profile/etc/profile.d ]; then
-  for i in $HOME/.nix-profile/etc/profile.d/*.sh; do
-    if [ -r $i ]; then
-      . $i
-    fi
-  done
-fi
-    </screen>
-
-    <para>
-      Now just run <literal>source $HOME/.profile</literal> and you can starting
-      loading man pages from your environent.
-    </para>
-
-  </section>
-    
-  <section xml:id="sec-gnu-info-setup">
-    <title>GNU info setup</title>
-
-    <para>
-      Configuring GNU info is a little bit trickier than man pages. To work
-      correctly, info needs a database to be generated. This can be done with
-      some small modifications to our environment scripts.
-    </para>
-
-    <screen>
-{
-  packageOverrides = pkgs: with pkgs; rec {
-    myProfile = writeText "my-profile" ''
-export PATH=$HOME/.nix-profile/bin:/nix/var/nix/profiles/default/bin:/sbin:/bin:/usr/sbin:/usr/bin
-export MANPATH=$HOME/.nix-profile/share/man:/nix/var/nix/profiles/default/share/man:/usr/share/man
-export INFOPATH=$HOME/.nix-profile/share/info:/nix/var/nix/profiles/default/share/info:/usr/share/info
-    '';
-    myPackages = pkgs.buildEnv {
-      name = "my-packages";
-      paths = [
-        (runCommand "profile" {} ''
-mkdir -p $out/etc/profile.d
-cp ${myProfile} $out/etc/profile.d/my-profile.sh
-        '')
-        aspell
-        bc
-        coreutils
-        ffmpeg
-        man
-        nixUnstable
-        emscripten
-        jq
-        nox
-        silver-searcher
-        texinfoInteractive
-      ];
-      pathsToLink = [ "/share/man" "/share/doc" "/share/info" "/bin" "/etc" ];
-      extraOutputsToInstall = [ "man" "doc" "info" ];
-      postBuild = ''
-          if [ -x $out/bin/install-info -a -w $out/share/info ]; then
-            shopt -s nullglob
-            for i in $out/share/info/*.info $out/share/info/*.info.gz; do
-                $out/bin/install-info $i $out/share/info/dir
-            done
-          fi
-      '';
-    };
-  };
-}
-    </screen>
-
-    <para>
-      <literal>postBuild</literal> tells Nixpkgs to run a command after building
-      the environment. In this case, <literal>install-info</literal> adds the
-      installed info pages to <literal>dir</literal> which is GNU info's default
-      root node. Note that <literal>texinfoInteractive</literal> is added to the
-      environment to give the <literal>install-info</literal> command.
-    </para>
-
-  </section>
-
-</section>

 </chapter>
--- a/doc/contributing.xml
+++ b/doc/contributing.xml
@@ -6,27 +6,12 @@

 <para>The DocBook sources of the Nixpkgs manual are in the <filename
 xlink:href="https://github.com/NixOS/nixpkgs/tree/master/doc">doc</filename>
-subdirectory of the Nixpkgs repository.</para>
-
-<para>You can quickly check your edits with <command>make</command>:</para>
+subdirectory of the Nixpkgs repository. If you make modifications to
+the manual, it's important to build it before committing. You can do that as follows:

 <screen>
-  $ cd /path/to/nixpkgs/doc
-  $ nix-shell
-  [nix-shell]$ make
-</screen>
-
-<para>If you experience problems, run <command>make debug</command>
-to help understand the docbook errors.</para>
-
-<para>After making modifications to the manual, it's important to
-build it before committing. You can do that as follows:
-
-<screen>
-  $ cd /path/to/nixpkgs/doc
-  $ nix-shell
-  [nix-shell]$ make clean
-  [nix-shell]$ nix-build .
+$ cd /path/to/nixpkgs
+$ nix-build doc
 </screen>

 If the build succeeds, the manual will be in
--- a/doc/cross-compilation.xml
+++ b/doc/cross-compilation.xml
@@ -11,7 +11,7 @@
    For example, a typical use of cross compilation is to compile programs for embedded devices.
    These devices often don't have the computing power and memory to compile their own programs.
    One might think that cross-compilation is a fairly niche concern, but there are advantages to being rigorous about distinguishing build-time vs run-time environments even when one is developing and deploying on the same machine.
-    Nixpkgs is increasingly adopting the opinion that packages should be written with cross-compilation in mind, and nixpkgs should evaluate in a similar way (by minimizing cross-compilation-specific special cases) whether or not one is cross-compiling.
+    Nixpkgs is increasingly adopting this opinion in that packages should be written with cross-compilation in mind, and nixpkgs should evaluate in a similar way (by minimizing cross-compilation-specific special cases) whether or not one is cross-compiling.
  </para>

  <para>
@@ -30,17 +30,23 @@
  <section>
    <title>Platform parameters</title>
    <para>
-      Nixpkgs follows the <link xlink:href="https://gcc.gnu.org/onlinedocs/gccint/Configure-Terms.html">common historical convention of GNU autoconf</link> of distinguishing between 3 types of platform: <wordasword>build</wordasword>, <wordasword>host</wordasword>, and <wordasword>target</wordasword>.
-
-      In summary, <wordasword>build</wordasword> is the platform on which a package is being built, <wordasword>host</wordasword> is the platform on which it is to run. The third attribute, <wordasword>target</wordasword>, is relevant only for certain specific compilers and build tools.
+      The three GNU Autoconf platforms, <wordasword>build</wordasword>, <wordasword>host</wordasword>, and <wordasword>cross</wordasword>, are historically the result of much confusion.
+      <link xlink:href="https://gcc.gnu.org/onlinedocs/gccint/Configure-Terms.html" /> clears this up somewhat but there is more to be said.
+      An important advice to get out the way is, unless you are packaging a compiler or other build tool, just worry about the build and host platforms.
+      Dealing with just two platforms usually better matches people's preconceptions, and in this case is completely correct.
    </para>
-
    <para>
      In Nixpkgs, these three platforms are defined as attribute sets under the names <literal>buildPlatform</literal>, <literal>hostPlatform</literal>, and <literal>targetPlatform</literal>.
-      All three are always defined as attributes in the standard environment, and at the top level. That means one can get at them just like a dependency in a function that is imported with <literal>callPackage</literal>:
-      <programlisting>{ stdenv, buildPlatform, hostPlatform, fooDep, barDep, .. }: ...buildPlatform...</programlisting>, or just off <varname>stdenv</varname>:
-      <programlisting>{ stdenv, fooDep, barDep, .. }: ...stdenv.buildPlatform...</programlisting>.
+      All are guaranteed to contain at least a <varname>platform</varname> field, which contains detailed information on the platform.
+      All three are always defined at the top level, so one can get at them just like a dependency in a function that is imported with <literal>callPackage</literal>:
+      <programlisting>{ stdenv, buildPlatform, hostPlatform, fooDep, barDep, .. }: ...</programlisting>
    </para>
+    <warning><para>
+      These platforms should all have the same structure in all scenarios, but that is currently not the case.
+      When not cross-compiling, they will each contain a <literal>system</literal> field with a short 2-part, hyphen-separated summering string name for the platform.
+      But, when when cross compiling, <literal>hostPlatform</literal> and <literal>targetPlatform</literal> may instead contain <literal>config</literal> with a fuller 3- or 4-part string in the manner of LLVM.
+      We should have all 3 platforms always contain both, and maybe give <literal>config</literal> a better name while we are at it.
+    </para></warning>
    <variablelist>
      <varlistentry>
        <term><varname>buildPlatform</varname></term>
@@ -52,7 +58,7 @@
      <varlistentry>
        <term><varname>hostPlatform</varname></term>
        <listitem><para>
-          The "host platform" is the platform on which a package will be run.
+          The "host platform" is the platform on which a package is run.
          This is the simplest platform to understand, but also the one with the worst name.
        </para></listitem>
      </varlistentry>
@@ -60,119 +66,44 @@
        <term><varname>targetPlatform</varname></term>
        <listitem>
          <para>
-            The "target platform" attribute is, unlike the other two attributes, not actually fundamental to the process of building software.
-            Instead, it is only relevant for compatibility with building certain specific compilers and build tools.
-            It can be safely ignored for all other packages.
+            The "target platform" is black sheep.
+            The other two intrinsically apply to all compiled software—or any build process with a notion of "build-time" followed by "run-time".
+            The target platform only applies to programming tools, and even then only is a good for for some of them.
+            Briefly, GCC, Binutils, GHC, and certain other tools are written in such a way such that a single build can only compiler code for a single platform.
+            Thus, when building them, one must think ahead about what platforms they wish to use the tool to produce machine code for, and build binaries for each.
          </para>
          <para>
-            The build process of certain compilers is written in such a way that the compiler resulting from a single build can itself only produce binaries for a single platform.
-            The task specifying this single "target platform" is thus pushed to build time of the compiler.
-            The root cause of this mistake is often that the compiler (which will be run on the host) and the the standard library/runtime (which will be run on the target) are built by a single build process.
+            There is no fundamental need to think about the target ahead of time like this.
+            LLVM, for example, was designed from the beginning with cross-compilation in mind, and so a normal LLVM binary will support every architecture that LLVM supports.
+            If the tool supports modular or pluggable backends, one might imagine specifying a <emphasis>set</emphasis> of target platforms / backends one wishes to support, rather than a single one.
          </para>
          <para>
-            There is no fundamental need to think about a single target ahead of time like this.
-            If the tool supports modular or pluggable backends, both the need to specify the target at build time and the constraint of having only a single target disappear.
-            An example of such a tool is LLVM.
+            The biggest reason for mess, if there is one, is that many compilers have the bad habit a build process that builds the compiler and standard library/runtime together.
+            Then the specifying target platform is essential, because it determines the host platform of the standard library/runtime.
+            Nixpkgs tries to avoid this where possible too, but still, because the concept of a target platform is so ingrained now in Autoconf and other tools, it is best to support it as is.
+            Tools like LLVM that don't need up-front target platforms can safely ignore it like normal packages, and it will do no harm.
          </para>
-          <para>
-            Although the existance of a "target platfom" is arguably a historical mistake, it is a common one: examples of tools that suffer from it are GCC, Binutils, GHC and Autoconf.
-            Nixpkgs tries to avoid sharing in the mistake where possible.
-            Still, because the concept of a target platform is so ingrained, it is best to support it as is.
-          </para>
-        </listitem>
-      </varlistentry>
-    </variablelist>
-    <para>
-      The exact schema these fields follow is a bit ill-defined due to a long and convoluted evolution, but this is slowly being cleaned up.
-      You can see examples of ones used in practice in <literal>lib.systems.examples</literal>; note how they are not all very consistent.
-      For now, here are few fields can count on them containing:
-    </para>
-    <variablelist>
-      <varlistentry>
-        <term><varname>system</varname></term>
-        <listitem>
-          <para>
-            This is a two-component shorthand for the platform.
-            Examples of this would be "x86_64-darwin" and "i686-linux"; see <literal>lib.systems.doubles</literal> for more.
-            This format isn't very standard, but has built-in support in Nix, such as the <varname>builtins.currentSystem</varname> impure string.
-          </para>
-        </listitem>
-      </varlistentry>
-      <varlistentry>
-        <term><varname>config</varname></term>
-        <listitem>
-          <para>
-            This is a 3- or 4- component shorthand for the platform.
-            Examples of this would be "x86_64-unknown-linux-gnu" and "aarch64-apple-darwin14".
-            This is a standard format called the "LLVM target triple", as they are pioneered by LLVM and traditionally just used for the <varname>targetPlatform</varname>.
-            This format is strictly more informative than the "Nix host double", as the previous format could analogously be termed.
-            This needs a better name than <varname>config</varname>!
-          </para>
-        </listitem>
-      </varlistentry>
-      <varlistentry>
-        <term><varname>parsed</varname></term>
-        <listitem>
-          <para>
-            This is a nix representation of a parsed LLVM target triple with white-listed components.
-            This can be specified directly, or actually parsed from the <varname>config</varname>.
-            [Technically, only one need be specified and the others can be inferred, though the precision of inference may not be very good.]
-            See <literal>lib.systems.parse</literal> for the exact representation.
-          </para>
-        </listitem>
-      </varlistentry>
-      <varlistentry>
-        <term><varname>libc</varname></term>
-        <listitem>
-          <para>
-            This is a string identifying the standard C library used.
-            Valid identifiers include "glibc" for GNU libc, "libSystem" for Darwin's Libsystem, and "uclibc" for µClibc.
-            It should probably be refactored to use the module system, like <varname>parse</varname>.
-          </para>
-        </listitem>
-      </varlistentry>
-      <varlistentry>
-        <term><varname>is*</varname></term>
-        <listitem>
-          <para>
-            These predicates are defined in <literal>lib.systems.inspect</literal>, and slapped on every platform.
-            They are superior to the ones in <varname>stdenv</varname> as they force the user to be explicit about which platform they are inspecting.
-            Please use these instead of those.
-          </para>
-        </listitem>
-      </varlistentry>
-      <varlistentry>
-        <term><varname>platform</varname></term>
-        <listitem>
-          <para>
-            This is, quite frankly, a dumping ground of ad-hoc settings (it's an attribute set).
-            See <literal>lib.systems.platforms</literal> for examples—there's hopefully one in there that will work verbatim for each platform that is working.
-            Please help us triage these flags and give them better homes!
-          </para>
-        </listitem>
+          </listitem>
      </varlistentry>
    </variablelist>
+    <note><para>
+      If you dig around nixpkgs, you may notice there is also <varname>stdenv.cross</varname>.
+      This field defined as <varname>hostPlatform</varname> when the host and build platforms differ, but otherwise not defined at all.
+      This field is obsolete and will soon disappear—please do not use it.
+    </para></note>
  </section>

  <section>
    <title>Specifying Dependencies</title>
    <para>
-      In this section we explore the relationship between both runtime and buildtime dependencies and the 3 Autoconf platforms.
-    </para>
-    <para>
-      A runtime dependency between 2 packages implies that between them both the host and target platforms match.
-      This is directly implied by the meaning of "host platform" and "runtime dependency":
-      The package dependency exists while both packages are running on a single host platform.
-    </para>
-    <para>
-      A build time dependency, however, implies a shift in platforms between the depending package and the depended-on package.
-      The meaning of a build time dependency is that to build the depending package we need to be able to run the depended-on's package.
-      The depending package's build platform is therefore equal to the depended-on package's host platform.
-      Analogously, the depending package's host platform is equal to the depended-on package's target platform.
-    </para>
-    <para>
-      In this manner, given the 3 platforms for one package, we can determine the three platforms for all its transitive dependencies.
+      As mentioned in the introduction to this chapter, one can think about a build time vs run time distinction whether cross-compiling or not.
+      In the case of cross-compilation, this corresponds with whether a derivation running on the native or foreign platform is produced.
+      An interesting thing to think about is how this corresponds with the three Autoconf platforms.
+      In the run-time case, the depending and depended-on package simply have matching build, host, and target platforms.
+      But in the build-time case, one can imagine "sliding" the platforms one over.
+      The depended-on package's host and target platforms (respectively) become the depending package's build and host platforms.
      This is the most important guiding principle behind cross-compilation with Nixpkgs, and will be called the <wordasword>sliding window principle</wordasword>.
+      In this manner, given the 3 platforms for one package, we can determine the three platforms for all its transitive dependencies.
    </para>
    <para>
      Some examples will probably make this clearer.
@@ -184,61 +115,17 @@
      The depending package's target platform is unconstrained by the sliding window principle, which makes sense in that one can in principle build cross compilers targeting arbitrary platforms.
    </para></note>
    <para>
-      How does this work in practice? Nixpkgs is now structured so that build-time dependencies are taken from <varname>buildPackages</varname>, whereas run-time dependencies are taken from the top level attribute set.
+      How does this work in practice? Nixpkgs is now structured so that build-time dependencies are taken from from <varname>buildPackages</varname>, whereas run-time dependencies are taken from the top level attribute set.
      For example, <varname>buildPackages.gcc</varname> should be used at build time, while <varname>gcc</varname> should be used at run time.
      Now, for most of Nixpkgs's history, there was no <varname>buildPackages</varname>, and most packages have not been refactored to use it explicitly.
-      Instead, one can use the six (<emphasis>gasp</emphasis>) attributes used for specifying dependencies as documented in <xref linkend="ssec-stdenv-dependencies"/>.
+      Instead, one can use the four attributes used for specifying dependencies as documented in <link linkend="ssec-stdenv-attributes" />.
      We "splice" together the run-time and build-time package sets with <varname>callPackage</varname>, and then <varname>mkDerivation</varname> for each of four attributes pulls the right derivation out.
      This splicing can be skipped when not cross compiling as the package sets are the same, but is a bit slow for cross compiling.
      Because of this, a best-of-both-worlds solution is in the works with no splicing or explicit access of <varname>buildPackages</varname> needed.
      For now, feel free to use either method.
    </para>
-    <note><para>
-      There is also a "backlink" <varname>targetPackages</varname>, yielding a package set whose <varname>buildPackages</varname> is the current package set.
-      This is a hack, though, to accommodate compilers with lousy build systems.
-      Please do not use this unless you are absolutely sure you are packaging such a compiler and there is no other way.
-    </para></note>
  </section>

-  <section>
-    <title>Cross packagaing cookbook</title>
-    <para>
-      Some frequently problems when packaging for cross compilation are good to just spell and answer.
-      Ideally the information above is exhaustive, so this section cannot provide any new information,
-      but its ludicrous and cruel to expect everyone to spend effort working through the interaction of many features just to figure out the same answer to the same common problem.
-      Feel free to add to this list!
-    </para>
-    <qandaset>
-      <qandaentry>
-        <question><para>
-          What if my package's build system needs to build a C program to be run under the build environment?
-        </para></question>
-        <answer><para>
-          <programlisting>depsBuildBuild = [ buildPackages.stdenv.cc ];</programlisting>
-          Add it to your <function>mkDerivation</function> invocation.
-        </para></answer>
-      </qandaentry>
-      <qandaentry>
-        <question><para>
-          My package fails to find <command>ar</command>.
-        </para></question>
-        <answer><para>
-          Many packages assume that an unprefixed <command>ar</command> is available, but Nix doesn't provide one.
-          It only provides a prefixed one, just as it only does for all the other binutils programs.
-          It may be necessary to patch the package to fix the build system to use a prefixed `ar`.
-        </para></answer>
-      </qandaentry>
-      <qandaentry>
-        <question><para>
-          My package's testsuite needs to run host platform code.
-        </para></question>
-        <answer><para>
-          <programlisting>doCheck = stdenv.hostPlatform != stdenv.buildPlatfrom;</programlisting>
-          Add it to your <function>mkDerivation</function> invocation.
-        </para></answer>
-      </qandaentry>
-    </qandaset>
-  </section>
 </section>

 <!--============================================================-->
@@ -249,38 +136,11 @@
    More information needs to moved from the old wiki, especially <link xlink:href="https://nixos.org/wiki/CrossCompiling" />, for this section.
  </para></note>
  <para>
-    Nixpkgs can be instantiated with <varname>localSystem</varname> alone, in which case there is no cross compiling and everything is built by and for that system,
-    or also with <varname>crossSystem</varname>, in which case packages run on the latter, but all building happens on the former.
-    Both parameters take the same schema as the 3 (build, host, and target) platforms defined in the previous section.
-    As mentioned above, <literal>lib.systems.examples</literal> has some platforms which are used as arguments for these parameters in practice.
-    You can use them programmatically, or on the command line: <programlisting>
-nix-build &lt;nixpkgs&gt; --arg crossSystem '(import &lt;nixpkgs/lib&gt;).systems.examples.fooBarBaz' -A whatever</programlisting>
+    Many sources (manual, wiki, etc) probably mention passing <varname>system</varname>, <varname>platform</varname>, and, optionally, <varname>crossSystem</varname> to nixpkgs:
+    <literal>import &lt;nixpkgs&gt; { system = ..; platform = ..; crossSystem = ..; }</literal>.
+    <varname>system</varname> and <varname>platform</varname> together determine the system on which packages are built, and <varname>crossSystem</varname> specifies the platform on which packages are ultimately intended to run, if it is different.
+    This still works, but with more recent changes, one can alternatively pass <varname>localSystem</varname>, containing <varname>system</varname> and <varname>platform</varname>, for symmetry.
  </para>
-  <note>
-    <para>
-      Eventually we would like to make these platform examples an unnecessary convenience so that <programlisting>
-nix-build &lt;nixpkgs&gt; --arg crossSystem.config '&lt;arch&gt;-&lt;os&gt;-&lt;vendor&gt;-&lt;abi&gt;' -A whatever</programlisting>
-      works in the vast majority of cases.
-      The problem today is dependencies on other sorts of configuration which aren't given proper defaults.
-      We rely on the examples to crudely to set those configuration parameters in some vaguely sane manner on the users behalf.
-      Issue <link xlink:href="https://github.com/NixOS/nixpkgs/issues/34274">#34274</link> tracks this inconvenience along with its root cause in crufty configuration options.
-    </para>
-  </note>
-  <para>
-    While one is free to pass both parameters in full, there's a lot of logic to fill in missing fields.
-    As discussed in the previous section, only one of <varname>system</varname>, <varname>config</varname>, and <varname>parsed</varname> is needed to infer the other two.
-    Additionally, <varname>libc</varname> will be inferred from <varname>parse</varname>.
-    Finally, <literal>localSystem.system</literal> is also <emphasis>impurely</emphasis> inferred based on the platform evaluation occurs.
-    This means it is often not necessary to pass <varname>localSystem</varname> at all, as in the command-line example in the previous paragraph.
-  </para>
-  <note>
-    <para>
-      Many sources (manual, wiki, etc) probably mention passing <varname>system</varname>, <varname>platform</varname>, along with the optional <varname>crossSystem</varname> to nixpkgs:
-      <literal>import &lt;nixpkgs&gt; { system = ..; platform = ..; crossSystem = ..; }</literal>.
-      Passing those two instead of <varname>localSystem</varname> is still supported for compatibility, but is discouraged.
-      Indeed, much of the inference we do for these parameters is motivated by compatibility as much as convenience.
-    </para>
-  </note>
  <para>
    One would think that <varname>localSystem</varname> and <varname>crossSystem</varname> overlap horribly with the three <varname>*Platforms</varname> (<varname>buildPlatform</varname>, <varname>hostPlatform,</varname> and <varname>targetPlatform</varname>; see <varname>stage.nix</varname> or the manual).
    Actually, those identifiers are purposefully not used here to draw a subtle but important distinction:
--- a/doc/default.nix
+++ b/doc/default.nix
@@ -7,41 +7,103 @@ in
 pkgs.stdenv.mkDerivation {
  name = "nixpkgs-manual";

-  buildInputs = with pkgs; [ pandoc libxml2 libxslt zip jing ];

-  src = ./.;
+  buildInputs = with pkgs; [ pandoc libxml2 libxslt zip ];

-  # Hacking on these variables? Make sure to close and open
-  # nix-shell between each test, maybe even:
-  # $ nix-shell --run "make clean all"
-  # otherwise they won't reapply :)
-  HIGHLIGHTJS = pkgs.documentation-highlighter;
-  XSL = "${pkgs.docbook5_xsl}/xml/xsl";
-  RNG = "${pkgs.docbook5}/xml/rng/docbook/docbook.rng";
-  xsltFlags = lib.concatStringsSep " " [
-    "--param section.autolabel 1"
-    "--param section.label.includes.component.label 1"
-    "--stringparam html.stylesheet 'style.css overrides.css highlightjs/mono-blue.css'"
-    "--stringparam html.script './highlightjs/highlight.pack.js ./highlightjs/loader.js'"
-    "--param xref.with.number.and.title 1"
-    "--param toc.section.depth 3"
-    "--stringparam admon.style ''"
-    "--stringparam callout.graphics.extension .svg"
-  ];
-
-  postPatch = ''
-    echo ${lib.nixpkgsVersion} > .version
+  xsltFlags = ''
+    --param section.autolabel 1
+    --param section.label.includes.component.label 1
+    --param html.stylesheet 'style.css'
+    --param xref.with.number.and.title 1
+    --param toc.section.depth 3
+    --param admon.style '''
+    --param callout.graphics.extension '.gif'
  '';

-  installPhase = ''
-    dest="$out/share/doc/nixpkgs"
-    mkdir -p "$(dirname "$dest")"
-    mv out/html "$dest"
-    mv "$dest/index.html" "$dest/manual.html"

-    mv out/epub/manual.epub "$dest/nixpkgs-manual.epub"
+  buildCommand = let toDocbook = { useChapters ? false, inputFile, outputFile }:
+    let
+      extraHeader = ''xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" '';
+    in ''
+      {
+        pandoc '${inputFile}' -w docbook ${lib.optionalString useChapters "--chapters"} \
+          --smart \
+          | sed -e 's|<ulink url=|<link xlink:href=|' \
+              -e 's|</ulink>|</link>|' \
+              -e 's|<sect. id=|<section xml:id=|' \
+              -e 's|</sect[0-9]>|</section>|' \
+              -e '1s| id=| xml:id=|' \
+              -e '1s|\(<[^ ]* \)|\1${extraHeader}|'
+      } > '${outputFile}'
+    '';
+  in

-    mkdir -p $out/nix-support/
-    echo "doc manual $dest manual.html" >> $out/nix-support/hydra-build-products
+  ''
+    ln -s '${sources}/'*.xml .
+    mkdir ./languages-frameworks
+    cp -s '${sources-langs}'/* ./languages-frameworks
+  ''
+  + toDocbook {
+      inputFile = ./introduction.md;
+      outputFile = "introduction.xml";
+      useChapters = true;
+    }
+  + toDocbook {
+      inputFile = ./languages-frameworks/python.md;
+      outputFile = "./languages-frameworks/python.xml";
+    }
+  + toDocbook {
+      inputFile = ./languages-frameworks/haskell.md;
+      outputFile = "./languages-frameworks/haskell.xml";
+    }
+  + toDocbook {
+      inputFile = ../pkgs/development/idris-modules/README.md;
+      outputFile = "languages-frameworks/idris.xml";
+    }
+  + toDocbook {
+      inputFile = ../pkgs/development/node-packages/README.md;
+      outputFile = "languages-frameworks/node.xml";
+    }
+  + toDocbook {
+      inputFile = ../pkgs/development/r-modules/README.md;
+      outputFile = "languages-frameworks/r.xml";
+    }
+  + toDocbook {
+      inputFile = ./languages-frameworks/vim.md;
+      outputFile = "./languages-frameworks/vim.xml";
+    }
+  + ''
+    echo ${lib.nixpkgsVersion} > .version
+
+    # validate against relaxng schema
+    xmllint --nonet --xinclude --noxincludenode manual.xml --output manual-full.xml
+    ${pkgs.jing}/bin/jing ${pkgs.docbook5}/xml/rng/docbook/docbook.rng manual-full.xml
+
+    dst=$out/share/doc/nixpkgs
+    mkdir -p $dst
+    xsltproc $xsltFlags --nonet --xinclude \
+      --output $dst/manual.html \
+      ${pkgs.docbook5_xsl}/xml/xsl/docbook/xhtml/docbook.xsl \
+      ./manual.xml
+
+    cp ${./style.css} $dst/style.css
+
+    mkdir -p $dst/images/callouts
+    cp "${pkgs.docbook5_xsl}/xml/xsl/docbook/images/callouts/"*.gif $dst/images/callouts/
+
+    mkdir -p $out/nix-support
+    echo "doc manual $dst manual.html" >> $out/nix-support/hydra-build-products
+
+    xsltproc $xsltFlags --nonet --xinclude \
+      --output $dst/epub/ \
+      ${pkgs.docbook5_xsl}/xml/xsl/docbook/epub/docbook.xsl \
+      ./manual.xml
+
+    cp -r $dst/images $dst/epub/OEBPS
+    echo "application/epub+zip" > mimetype
+    manual="$dst/nixpkgs-manual.epub"
+    zip -0Xq "$manual" mimetype
+    cd $dst/epub && zip -Xr9D "$manual" *
+    rm -rf $dst/epub
  '';
 }
--- a/doc/functions.xml
+++ b/doc/functions.xml
@@ -70,7 +70,7 @@

    <para>
      In the above example, the <varname>separateDebugInfo</varname> attribute is
-      overridden to be true, thus building debug info for
+      overriden to be true, thus building debug info for
      <varname>helloWithDebug</varname>, while all other attributes will be
      retained from the original <varname>hello</varname> package.
    </para>
@@ -358,8 +358,8 @@
 <para>
  <varname>pkgs.dockerTools</varname> is a set of functions for creating and
  manipulating Docker images according to the
-  <link xlink:href="https://github.com/moby/moby/blob/master/image/spec/v1.2.md#docker-image-specification-v120">
-  Docker Image Specification v1.2.0
+  <link xlink:href="https://github.com/docker/docker/blob/master/image/spec/v1.md#docker-image-specification-v100">
+  Docker Image Specification v1.0.0
  </link>. Docker itself is not used to perform any of the operations done by these
  functions.
 </para>
@@ -493,8 +493,8 @@
    <varname>config</varname> is used to specify the configuration of the
    containers that will be started off the built image in Docker.
    The available options are listed in the
-    <link xlink:href="https://github.com/moby/moby/blob/master/image/spec/v1.2.md#image-json-field-descriptions">
-      Docker Image Specification v1.2.0
+    <link xlink:href="https://github.com/docker/docker/blob/master/image/spec/v1.md#container-runconfig-field-descriptions">
+      Docker Image Specification v1.0.0
    </link>.
    </para>
  </callout>
@@ -529,7 +529,7 @@
  <note>
  <para>
  If you see errors similar to <literal>getProtocolByName: does not exist (no such protocol name: tcp)</literal>
-  you may need to add <literal>pkgs.iana-etc</literal> to <varname>contents</varname>.
+  you may need to add <literal>pkgs.iana_etc</literal> to <varname>contents</varname>.
  </para>
  </note>

--- a/doc/introduction.chapter.md
+++ b/doc/introduction.chapter.md
@@ -1,51 +0,0 @@
---
-title: Introduction
-author: Frederik Rietdijk
-date: 2015-11-25
---
-
-# Introduction
-
-The Nix Packages collection (Nixpkgs) is a set of thousands of packages for the
-[Nix package manager](http://nixos.org/nix/), released under a
-[permissive MIT/X11 license](https://github.com/NixOS/nixpkgs/blob/master/COPYING).
-Packages are available for several platforms, and can be used with the Nix
-package manager on most GNU/Linux distributions as well as NixOS.
-
-This manual primarily describes how to write packages for the Nix Packages collection
-(Nixpkgs). Thus it’s mainly for packagers and developers who want to add packages to
-Nixpkgs. If you like to learn more about the Nix package manager and the Nix
-expression language, then you are kindly referred to the [Nix manual](http://nixos.org/nix/manual/).
-
-## Overview of Nixpkgs
-
-Nix expressions describe how to build packages from source and are collected in
-the [nixpkgs repository](https://github.com/NixOS/nixpkgs). Also included in the
-collection are Nix expressions for
-[NixOS modules](http://nixos.org/nixos/manual/index.html#sec-writing-modules).
-With these expressions the Nix package manager can build binary packages.
-
-Packages, including the Nix packages collection, are distributed through
-[channels](http://nixos.org/nix/manual/#sec-channels). The collection is
-distributed for users of Nix on non-NixOS distributions through the channel
-`nixpkgs`. Users of NixOS generally use one of the `nixos-*` channels, e.g.
-`nixos-16.03`, which includes all packages and modules for the stable NixOS
-16.03. The purpose of stable NixOS releases are generally only given
-security updates. More up to date packages and modules are available via the
-`nixos-unstable` channel.
-
-Both `nixos-unstable` and `nixpkgs` follow the `master` branch of the Nixpkgs
-repository, although both do lag the `master` branch by generally
-[a couple of days](http://howoldis.herokuapp.com/). Updates to a channel are
-distributed as soon as all tests for that channel pass, e.g.
-[this table](http://hydra.nixos.org/job/nixpkgs/trunk/unstable#tabs-constituents)
-shows the status of tests for the `nixpkgs` channel.
-
-The tests are conducted by a cluster called [Hydra](http://nixos.org/hydra/),
-which also builds binary packages from the Nix expressions in Nixpkgs for
-`x86_64-linux`, `i686-linux` and `x86_64-darwin`.
-The binaries are made available via a [binary cache](https://cache.nixos.org).
-
-The current Nix expressions of the channels are available in the
-[`nixpkgs-channels`](https://github.com/NixOS/nixpkgs-channels) repository,
-which has branches corresponding to the available channels.
--- a/doc/introduction.md
+++ b/doc/introduction.md
@@ -0,0 +1,53 @@
+---
+title: Introduction
+author: Frederik Rietdijk
+date: 2015-11-25
+---
+
+# Introduction
+
+The Nix Packages collection (Nixpkgs) is a set of thousands of packages for the
+[Nix package manager](http://nixos.org/nix/), released under a
+[permissive MIT/X11 license](https://github.com/NixOS/nixpkgs/blob/master/COPYING).
+Packages are available for several platforms, and can be used with the Nix
+package manager on most GNU/Linux distributions as well as NixOS.
+
+This manual primarily describes how to write packages for the Nix Packages collection
+(Nixpkgs). Thus it’s mainly for packagers and developers who want to add packages to
+Nixpkgs. If you like to learn more about the Nix package manager and the Nix
+expression language, then you are kindly referred to the [Nix manual](http://nixos.org/nix/manual/).
+
+## Overview of Nixpkgs
+
+Nix expressions describe how to build packages from source and are collected in
+the [nixpkgs repository](https://github.com/NixOS/nixpkgs). Also included in the
+collection are Nix expressions for
+[NixOS modules](http://nixos.org/nixos/manual/index.html#sec-writing-modules).
+With these expressions the Nix package manager can build binary packages.
+
+Packages, including the Nix packages collection, are distributed through
+[channels](http://nixos.org/nix/manual/#sec-channels). The collection is
+distributed for users of Nix on non-NixOS distributions through the channel
+`nixpkgs`. Users of NixOS generally use one of the `nixos-*` channels, e.g.
+`nixos-16.03`, which includes all packages and modules for the stable NixOS
+16.03. The purpose of stable NixOS releases are generally only given
+security updates. More up to date packages and modules are available via the
+`nixos-unstable` channel.
+
+Both `nixos-unstable` and `nixpkgs` follow the `master` branch of the Nixpkgs
+repository, although both do lag the `master` branch by generally
+[a couple of days](http://howoldis.herokuapp.com/). Updates to a channel are
+distributed as soon as all tests for that channel pass, e.g.
+[this table](http://hydra.nixos.org/job/nixpkgs/trunk/unstable#tabs-constituents)
+shows the status of tests for the `nixpkgs` channel.
+
+The tests are conducted by a cluster called [Hydra](http://nixos.org/hydra/),
+which also builds binary packages from the Nix expressions in Nixpkgs for
+`x86_64-linux`, `i686-linux` and `x86_64-darwin`.
+The binaries are made available via a [binary cache](https://cache.nixos.org).
+
+The current Nix expressions of the channels are available in the
+[`nixpkgs-channels`](https://github.com/NixOS/nixpkgs-channels) repository,
+which has branches corresponding to the available channels. There is also the
+[Nixpkgs Monitor](http://monitor.nixos.org) which keeps track of updates
+and security vulnerabilities.
--- a/doc/languages-frameworks/beam.xml
+++ b/doc/languages-frameworks/beam.xml
@@ -2,120 +2,60 @@
         xmlns:xlink="http://www.w3.org/1999/xlink"
         xml:id="sec-beam">

-  <title>BEAM Languages (Erlang, Elixir &amp; LFE)</title>
+  <title>Beam Languages (Erlang &amp; Elixir)</title>
  <section xml:id="beam-introduction">
    <title>Introduction</title>
    <para>
-      In this document and related Nix expressions, we use the term,
-      <emphasis>BEAM</emphasis>, to describe the environment. BEAM is the name
-      of the Erlang Virtual Machine and, as far as we're concerned, from a
-      packaging perspective, all languages that run on the BEAM are
-      interchangeable. That which varies, like the build system, is transparent
-      to users of any given BEAM package, so we make no distinction.
+      In this document and related Nix expressions we use the term
+      <emphasis>Beam</emphasis> to describe the environment. Beam is
+      the name of the Erlang Virtial Machine and, as far as we know,
+      from a packaging perspective all languages that run on Beam are
+      interchangable. The things that do change, like the build
+      system, are transperant to the users of the package. So we make
+      no distinction.
    </para>
  </section>
-  <section xml:id="beam-structure">
-    <title>Structure</title>
-    <para>
-      All BEAM-related expressions are available via the top-level
-      <literal>beam</literal> attribute, which includes:
-    </para>
-    <itemizedlist>
-      <listitem>
-        <para>
-          <literal>interpreters</literal>: a set of compilers running on the
-          BEAM, including multiple Erlang/OTP versions
-          (<literal>beam.interpreters.erlangR19</literal>, etc), Elixir
-          (<literal>beam.interpreters.elixir</literal>) and LFE
-          (<literal>beam.interpreters.lfe</literal>).
-        </para>
-      </listitem>
-      <listitem>
-        <para>
-          <literal>packages</literal>: a set of package sets, each compiled with
-          a specific Erlang/OTP version, e.g.
-          <literal>beam.packages.erlangR19</literal>.
-        </para>
-      </listitem>
-    </itemizedlist>
-    <para>
-      The default Erlang compiler, defined by
-      <literal>beam.interpreters.erlang</literal>, is aliased as
-      <literal>erlang</literal>. The default BEAM package set is defined by
-      <literal>beam.packages.erlang</literal> and aliased at the top level as
-      <literal>beamPackages</literal>.
-    </para>
-    <para>
-      To create a package set built with a custom Erlang version, use the
-      lambda, <literal>beam.packagesWith</literal>, which accepts an Erlang/OTP
-      derivation and produces a package set similar to
-      <literal>beam.packages.erlang</literal>.
-    </para>
-    <para>
-      Many Erlang/OTP distributions available in
-      <literal>beam.interpreters</literal> have versions with ODBC and/or Java
-      enabled. For example, there's
-      <literal>beam.interpreters.erlangR19_odbc_javac</literal>, which
-      corresponds to <literal>beam.interpreters.erlangR19</literal>.
-    </para>
-    <para xml:id="erlang-call-package">
-      We also provide the lambda,
-      <literal>beam.packages.erlang.callPackage</literal>, which simplifies
-      writing BEAM package definitions by injecting all packages from
-      <literal>beam.packages.erlang</literal> into the top-level context.
-    </para>
-  </section>
-  <section xml:id="build-tools">
+<section xml:id="build-tools">
  <title>Build Tools</title>
  <section xml:id="build-tools-rebar3">
    <title>Rebar3</title>
    <para>
-      By default, Rebar3 wants to manage its own dependencies. This is perfectly
-      acceptable in the normal, non-Nix setup, but in the Nix world, it is not.
-      To rectify this, we provide two versions of Rebar3:
-      <itemizedlist>
-        <listitem>
-          <para>
-            <literal>rebar3</literal>: patched to remove the ability to download
-            anything. When not running it via <literal>nix-shell</literal> or
-            <literal>nix-build</literal>, it's probably not going to work as
-            desired.
-          </para>
-        </listitem>
-        <listitem>
-          <para>
-            <literal>rebar3-open</literal>: the normal, unmodified Rebar3. It
-            should work exactly as would any other version of Rebar3. Any Erlang
-            package should rely on <literal>rebar3</literal> instead. See <xref
-            linkend="rebar3-packages"/>.
-          </para>
-        </listitem>
-      </itemizedlist>
+      By default Rebar3 wants to manage it's own dependencies. In the
+      normal non-Nix, this is perfectly acceptable. In the Nix world it
+      is not. To support this we have created two versions of rebar3,
+      <literal>rebar3</literal> and <literal>rebar3-open</literal>. The
+      <literal>rebar3</literal> version has been patched to remove the
+      ability to download anything from it. If you are not running it a
+      nix-shell or a nix-build then its probably not going to work for
+      you. <literal>rebar3-open</literal> is the normal, un-modified
+      rebar3. It should work exactly as would any other version of
+      rebar3. Any Erlang package should rely on
+      <literal>rebar3</literal> and thats really what you should be
+      using too.
    </para>
  </section>
  <section xml:id="build-tools-other">
    <title>Mix &amp; Erlang.mk</title>
    <para>
-      Both Mix and Erlang.mk work exactly as expected. There is a bootstrap
-      process that needs to be run for both, however, which is supported by the
-      <literal>buildMix</literal> and <literal>buildErlangMk</literal>
-      derivations, respectively.
+      Both Mix and Erlang.mk work exactly as you would expect. There
+      is a bootstrap process that needs to be run for both of
+      them. However, that is supported by the
+      <literal>buildMix</literal> and <literal>buildErlangMk</literal> derivations.
    </para>
  </section>
+
 </section>

 <section xml:id="how-to-install-beam-packages">
-  <title>How to Install BEAM Packages</title>
+  <title>How to install Beam packages</title>
  <para>
-    BEAM packages are not registered at the top level, simply because they are
-    not relevant to the vast majority of Nix users. They are installable using
-    the <literal>beam.packages.erlang</literal> attribute set (aliased as
-    <literal>beamPackages</literal>), which points to packages built by the
-    default Erlang/OTP version in Nixpkgs, as defined by
-    <literal>beam.interpreters.erlang</literal>.
+    Beam packages are not registered in the top level simply because
+    they are not relevant to the vast majority of Nix users. They are
+    installable using the <literal>beamPackages</literal> attribute
+    set.

-    To list the available packages in
-    <literal>beamPackages</literal>, use the following command:
+    You can list the avialable packages in the
+    <literal>beamPackages</literal> with the following command:
  </para>

  <programlisting>
@@ -129,152 +69,115 @@ beamPackages.meck       meck-0.8.3
 beamPackages.rebar3-pc  pc-1.1.0
  </programlisting>
  <para>
-    To install any of those packages into your profile, refer to them by their
-    attribute path (first column):
+    To install any of those packages into your profile, refer to them by
+    their attribute path (first column):
  </para>
  <programlisting>
 $ nix-env -f &quot;&lt;nixpkgs&gt;&quot; -iA beamPackages.ibrowse
  </programlisting>
  <para>
-    The attribute path of any BEAM package corresponds to the name of that
-    particular package in <link xlink:href="https://hex.pm">Hex</link> or its
-    OTP Application/Release name.
+    The attribute path of any Beam packages corresponds to the name
+    of that particular package in Hex or its OTP Application/Release name.
  </para>
 </section>
 <section xml:id="packaging-beam-applications">
-  <title>Packaging BEAM Applications</title>
+  <title>Packaging Beam Applications</title>
  <section  xml:id="packaging-erlang-applications">
    <title>Erlang Applications</title>
    <section xml:id="rebar3-packages">
      <title>Rebar3 Packages</title>
      <para>
-        The Nix function, <literal>buildRebar3</literal>, defined in
-        <literal>beam.packages.erlang.buildRebar3</literal> and aliased at the
-        top level, can be used to build a derivation that understands how to
-        build a Rebar3 project. For example, we can build <link
-        xlink:href="https://github.com/erlang-nix/hex2nix">hex2nix</link> as
-        follows:
+        There is a Nix functional called
+        <literal>buildRebar3</literal>. We use this function to make a
+        derivation that understands how to build the rebar3 project. For
+        example, the epression we use to build the <link
+        xlink:href="https://github.com/erlang-nix/hex2nix">hex2nix</link>
+        project follows.
      </para>
      <programlisting>
-        { stdenv, fetchFromGitHub, buildRebar3, ibrowse, jsx, erlware_commons }:
+        {stdenv, fetchFromGitHub, buildRebar3, ibrowse, jsx, erlware_commons }:

-        buildRebar3 rec {
-          name = "hex2nix";
-          version = "0.0.1";
+          buildRebar3 rec {
+            name = "hex2nix";
+            version = "0.0.1";

-          src = fetchFromGitHub {
-            owner = "ericbmerritt";
-            repo = "hex2nix";
-            rev = "${version}";
-            sha256 = "1w7xjidz1l5yjmhlplfx7kphmnpvqm67w99hd2m7kdixwdxq0zqg";
-          };
+            src = fetchFromGitHub {
+              owner = "ericbmerritt";
+              repo = "hex2nix";
+              rev = "${version}";
+              sha256 = "1w7xjidz1l5yjmhlplfx7kphmnpvqm67w99hd2m7kdixwdxq0zqg";
+            };

          beamDeps = [ ibrowse jsx erlware_commons ];
        }
      </programlisting>
      <para>
-        Such derivations are callable with
-        <literal>beam.packages.erlang.callPackage</literal> (see <xref
-        linkend="erlang-call-package"/>). To call this package using the normal
-        <literal>callPackage</literal>, refer to dependency packages via
-        <literal>beamPackages</literal>, e.g.
-        <literal>beamPackages.ibrowse</literal>.
+        The only visible difference between this derivation and
+        something like <literal>stdenv.mkDerivation</literal> is that we
+        have added <literal>erlangDeps</literal> to the derivation. If
+        you add your Beam dependencies here they will be correctly
+        handled by the system.
      </para>
      <para>
-        Notably, <literal>buildRebar3</literal> includes
-        <literal>beamDeps</literal>, while
-        <literal>stdenv.mkDerivation</literal> does not. BEAM dependencies added
-        there will be correctly handled by the system.
-      </para>
-      <para>
-        If a package needs to compile native code via Rebar3's port compilation
-        mechanism, add <literal>compilePort = true;</literal> to the derivation.
+        If your package needs to compile native code via Rebar's port
+        compilation mechenism. You should add <literal>compilePort =
+        true;</literal> to the derivation.
      </para>
    </section>
    <section xml:id="erlang-mk-packages">
      <title>Erlang.mk Packages</title>
      <para>
-        Erlang.mk functions similarly to Rebar3, except we use
-        <literal>buildErlangMk</literal> instead of
-        <literal>buildRebar3</literal>.
+        Erlang.mk functions almost identically to Rebar. The only real
+        difference is that <literal>buildErlangMk</literal> is called
+        instead of <literal>buildRebar3</literal>
      </para>
      <programlisting>
-        { buildErlangMk, fetchHex, cowlib, ranch }:
-
-        buildErlangMk {
-          name = "cowboy";
-          version = "1.0.4";
-
-          src = fetchHex {
-            pkg = "cowboy";
+        { buildErlangMk, fetchHex,  cowlib, ranch }:
+          buildErlangMk {
+            name = "cowboy";
            version = "1.0.4";
-            sha256 = "6a0edee96885fae3a8dd0ac1f333538a42e807db638a9453064ccfdaa6b9fdac";
-          };
+            src = fetchHex {
+              pkg = "cowboy";
+              version = "1.0.4";
+              sha256 =
+                "6a0edee96885fae3a8dd0ac1f333538a42e807db638a9453064ccfdaa6b9fdac";
+            };
+            beamDeps  = [ cowlib ranch ];

-          beamDeps = [ cowlib ranch ];
-
-          meta = {
-            description = ''
-              Small, fast, modular HTTP server written in Erlang
-            '';
-            license = stdenv.lib.licenses.isc;
-            homepage = https://github.com/ninenines/cowboy;
-          };
+            meta = {
+              description = ''Small, fast, modular HTTP server written in
+                            Erlang.'';
+              license = stdenv.lib.licenses.isc;
+              homepage = "https://github.com/ninenines/cowboy";
+            };
        }
      </programlisting>
    </section>
    <section xml:id="mix-packages">
      <title>Mix Packages</title>
      <para>
-        Mix functions similarly to Rebar3, except we use
-        <literal>buildMix</literal> instead of <literal>buildRebar3</literal>.
+        Mix functions almost identically to Rebar. The only real
+        difference is that <literal>buildMix</literal> is called
+        instead of <literal>buildRebar3</literal>
      </para>
      <programlisting>
        { buildMix, fetchHex, plug, absinthe }:
-
        buildMix {
          name = "absinthe_plug";
          version = "1.0.0";
-
          src = fetchHex {
            pkg = "absinthe_plug";
            version = "1.0.0";
-            sha256 = "08459823fe1fd4f0325a8bf0c937a4520583a5a26d73b193040ab30a1dfc0b33";
+            sha256 =
+              "08459823fe1fd4f0325a8bf0c937a4520583a5a26d73b193040ab30a1dfc0b33";
          };
-
-          beamDeps = [ plug absinthe ];
+          beamDeps  = [ plug absinthe];

          meta = {
-            description = ''
-              A plug for Absinthe, an experimental GraphQL toolkit
-            '';
+            description = ''A plug for Absinthe, an experimental GraphQL
+                            toolkit'';
            license = stdenv.lib.licenses.bsd3;
-            homepage = https://github.com/CargoSense/absinthe_plug;
-          };
-        }
-      </programlisting>
-      <para>
-        Alternatively, we can use <literal>buildHex</literal> as a shortcut:
-      </para>
-      <programlisting>
-        { buildHex, buildMix, plug, absinthe }:
-
-        buildHex {
-          name = "absinthe_plug";
-          version = "1.0.0";
-
-          sha256 = "08459823fe1fd4f0325a8bf0c937a4520583a5a26d73b193040ab30a1dfc0b33";
-
-          builder = buildMix;
-
-          beamDeps = [ plug absinthe ];
-
-          meta = {
-            description = ''
-              A plug for Absinthe, an experimental GraphQL toolkit
-            '';
-            license = stdenv.lib.licenses.bsd3;
-            homepage = https://github.com/CargoSense/absinthe_plug;
+            homepage = "https://github.com/CargoSense/absinthe_plug";
         };
       }
      </programlisting>
@@ -282,18 +185,18 @@ $ nix-env -f &quot;&lt;nixpkgs&gt;&quot; -iA beamPackages.ibrowse
  </section>
 </section>
 <section xml:id="how-to-develop">
-  <title>How to Develop</title>
+  <title>How to develop</title>
  <section xml:id="accessing-an-environment">
    <title>Accessing an Environment</title>
    <para>
-      Often, we simply want to access a valid environment that contains a
-      specific package and its dependencies. We can accomplish that with the
-      <literal>env</literal> attribute of a derivation. For example, let's say
-      we want to access an Erlang REPL with <literal>ibrowse</literal> loaded
-      up. We could do the following:
+      Often, all you want to do is be able to access a valid
+      environment that contains a specific package and its
+      dependencies. we can do that with the <literal>env</literal>
+      part of a derivation. For example, lets say we want to access an
+      erlang repl with ibrowse loaded up. We could do the following.
    </para>
    <programlisting>
-      $ nix-shell -A beamPackages.ibrowse.env --run "erl"
+      ~/w/nixpkgs ❯❯❯ nix-shell -A beamPackages.ibrowse.env --run "erl"
      Erlang/OTP 18 [erts-7.0] [source] [64-bit] [smp:4:4] [async-threads:10] [hipe] [kernel-poll:false]

      Eshell V7.0  (abort with ^G)
@@ -334,19 +237,20 @@ $ nix-env -f &quot;&lt;nixpkgs&gt;&quot; -iA beamPackages.ibrowse
      2>
    </programlisting>
    <para>
-      Notice the <literal>-A beamPackages.ibrowse.env</literal>. That is the key
-      to this functionality.
+      Notice the <literal>-A beamPackages.ibrowse.env</literal>.That
+      is the key to this functionality.
    </para>
  </section>
  <section xml:id="creating-a-shell">
    <title>Creating a Shell</title>
    <para>
      Getting access to an environment often isn't enough to do real
-      development. Usually, we need to create a <literal>shell.nix</literal>
-      file and do our development inside of the environment specified therein.
-      This file looks a lot like the packaging described above, except that
-      <literal>src</literal> points to the project root and we call the package
-      directly.
+      development. Many times we need to create a
+      <literal>shell.nix</literal> file and do our development inside
+      of the environment specified by that file. This file looks a lot
+      like the packaging described above. The main difference is that
+      <literal>src</literal> points to project root and we call the
+      package directly.
    </para>
    <programlisting>
 { pkgs ? import &quot;&lt;nixpkgs&quot;&gt; {} }:
@@ -360,19 +264,18 @@ let
        name = "hex2nix";
        version = "0.1.0";
        src = ./.;
-        beamDeps = [ ibrowse jsx erlware_commons ];
+        erlangDeps = [ ibrowse jsx erlware_commons ];
      };
  drv = beamPackages.callPackage f {};

 in
-
-  drv
+ drv
    </programlisting>
    <section xml:id="building-in-a-shell">
-    <title>Building in a Shell (for Mix Projects)</title>
+    <title>Building in a shell</title>
    <para>
-      We can leverage the support of the derivation, irrespective of the build
-      derivation, by calling the commands themselves.
+      We can leveral the support of the Derivation, regardless of
+      which build Derivation is called by calling the commands themselv.s
    </para>
    <programlisting>
 # =============================================================================
@@ -432,43 +335,42 @@ analyze: build plt

    </programlisting>
    <para>
-      Using a <literal>shell.nix</literal> as described (see <xref
-      linkend="creating-a-shell"/>) should just work. Aside from
+      If you add the <literal>shell.nix</literal> as described and
+      user rebar as follows things should simply work. Aside from the
      <literal>test</literal>, <literal>plt</literal>, and
-      <literal>analyze</literal>, the Make targets work just fine for all of the
-      build derivations.
+      <literal>analyze</literal> the talks work just fine for all of
+      the build Derivations.
    </para>
  </section>
 </section>
 </section>
 <section xml:id="generating-packages-from-hex-with-hex2nix">
-  <title>Generating Packages from Hex with <literal>hex2nix</literal></title>
+  <title>Generating Packages from Hex with Hex2Nix</title>
  <para>
-    Updating the <link xlink:href="https://hex.pm">Hex</link> package set
-    requires <link
-    xlink:href="https://github.com/erlang-nix/hex2nix">hex2nix</link>. Given the
-    path to the Erlang modules (usually
-    <literal>pkgs/development/erlang-modules</literal>), it will dump a file
-    called <literal>hex-packages.nix</literal>, containing all the packages that
-    use a recognized build system in <link
-    xlink:href="https://hex.pm">Hex</link>. It can't be determined, however,
-    whether every package is buildable.
+    Updating the Hex packages requires the use of the
+    <literal>hex2nix</literal> tool. Given the path to the Erlang
+    modules (usually
+    <literal>pkgs/development/erlang-modules</literal>). It will
+    happily dump a file called
+    <literal>hex-packages.nix</literal>. That file will contain all
+    the packages that use a recognized build system in Hex. However,
+    it can't know whether or not all those packages are buildable.
    </para>
    <para>
-      To make life easier for our users, try to build every <link
-      xlink:href="https://hex.pm">Hex</link> package and remove those that fail.
-      To do that, simply run the following command in the root of your
-      <literal>nixpkgs</literal> repository:
+      To make life easier for our users, it makes good sense to go
+      ahead and attempt to build all those packages and remove the
+      ones that don't build. To do that, simply run the command (in
+      the root of your <literal>nixpkgs</literal> repository). that follows.
    </para>
    <programlisting>
 $ nix-build -A beamPackages
    </programlisting>
    <para>
-      That will attempt to build every package in
-      <literal>beamPackages</literal>. Then manually remove those that fail.
-      Hopefully, someone will improve <link
-      xlink:href="https://github.com/erlang-nix/hex2nix">hex2nix</link> in the
-      future to automate the process.
+      That will build every package in
+      <literal>beamPackages</literal>. Then you can go through and
+      manually remove the ones that fail. Hopefully, someone will
+      improve <literal>hex2nix</literal> in the future to automate
+      that.
    </para>
 </section>
 </section>
--- a/doc/languages-frameworks/coq.xml
+++ b/doc/languages-frameworks/coq.xml
@@ -11,53 +11,31 @@
    in the Coq derivation.
  </para>
  <para>
-    Some libraries require OCaml and sometimes also Camlp5 or findlib.
-    The exact versions that were used to build Coq are saved in the
+    Some libraries require OCaml and sometimes also Camlp5. The exact
+    versions that were used to build Coq are saved in the
    <literal>coq.ocaml</literal> and <literal>coq.camlp5</literal>
-    and <literal>coq.findlib</literal> attributes.
-  </para>
-  <para>
-    Coq libraries may be compatible with some specific versions of Coq only.
-    The <literal>compatibleCoqVersions</literal> attribute is used to
-    precisely select those versions of Coq that are compatible with this
-    derivation.
+    attributes.
  </para>
  <para>
    Here is a simple package example. It is a pure Coq library, thus it
-    depends on Coq. It builds on the Mathematical Components library, thus it
-    also takes <literal>mathcomp</literal> as <literal>buildInputs</literal>.
-    Its <literal>Makefile</literal> has been generated using
-    <literal>coq_makefile</literal> so we only have to
+    only depends on Coq. Its <literal>makefile</literal> has been
+    generated using <literal>coq_makefile</literal> so we only have to
    set the <literal>$COQLIB</literal> variable at install time.
  </para>
  <programlisting>
-{ stdenv, fetchFromGitHub, coq, mathcomp }:
-
-stdenv.mkDerivation rec {
-  name = "coq${coq.coq-version}-multinomials-${version}";
-  version = "1.0";
-  src = fetchFromGitHub {
-    owner = "math-comp";
-    repo = "multinomials";
-    rev = version;
-    sha256 = "1qmbxp1h81cy3imh627pznmng0kvv37k4hrwi2faa101s6bcx55m";
+{stdenv, fetchurl, coq}:
+stdenv.mkDerivation {
+  src = fetchurl {
+    url = http://coq.inria.fr/pylons/contribs/files/Karatsuba/v8.4/Karatsuba.tar.gz;
+    sha256 = "0ymfpv4v49k4fm63nq6gcl1hbnnxrvjjp7yzc4973n49b853c5b1";
  };

+  name = "coq-karatsuba";
+
  buildInputs = [ coq ];
-  propagatedBuildInputs = [ mathcomp ];

  installFlags = "COQLIB=$(out)/lib/coq/${coq.coq-version}/";
-
-  meta = {
-    description = "A Coq/SSReflect Library for Monoidal Rings and Multinomials";
-    inherit (src.meta) homepage;
-    license = stdenv.lib.licenses.cecill-b;
-    inherit (coq.meta) platforms;
-  };
-
-  passthru = {
-    compatibleCoqVersions = v: builtins.elem v [ "8.5" "8.6" "8.7" ];
-  };
 }
 </programlisting>
 </section>
+
--- a/doc/languages-frameworks/go.xml
+++ b/doc/languages-frameworks/go.xml
@@ -13,7 +13,7 @@ standard Go programs.
 deis = buildGoPackage rec {
  name = "deis-${version}";
  version = "1.13.0";
-
+  
  goPackagePath = "github.com/deis/deis"; <co xml:id='ex-buildGoPackage-1' />
  subPackages = [ "client" ]; <co xml:id='ex-buildGoPackage-2' />

@@ -130,9 +130,6 @@ the following arguments are of special significance to the function:

 </para>

-<para>To extract dependency information from a Go package in automated way use <link xlink:href="https://github.com/kamilchm/go2nix">go2nix</link>.
-  It can produce complete derivation and <varname>goDeps</varname> file for Go programs.</para>
-
 <para>
  <varname>buildGoPackage</varname> produces <xref linkend='chap-multiple-output' xrefstyle="select: title" />
  where <varname>bin</varname> includes program binaries. You can test build a Go binary as follows:
@@ -163,4 +160,7 @@ done
 </screen>
 </para>

+<para>To extract dependency information from a Go package in automated way use <link xlink:href="https://github.com/kamilchm/go2nix">go2nix</link>.
+  It can produce complete derivation and <varname>goDeps</varname> file for Go programs.</para>
 </section>
+
--- a/doc/languages-frameworks/haskell.md
+++ b/doc/languages-frameworks/haskell.md
@@ -0,0 +1,883 @@
+---
+title: User's Guide for Haskell in Nixpkgs
+author: Peter Simons
+date: 2015-06-01
+---
+# User's Guide to the Haskell Infrastructure
+
+
+## How to install Haskell packages
+
+Nixpkgs distributes build instructions for all Haskell packages registered on
+[Hackage](http://hackage.haskell.org/), but strangely enough normal Nix package
+lookups don't seem to discover any of them, except for the default version of ghc, cabal-install, and stack:
+
+    $ nix-env -i alex
+    error: selector ‘alex’ matches no derivations
+    $ nix-env -qa ghc
+    ghc-7.10.2
+
+The Haskell package set is not registered in the top-level namespace because it
+is *huge*. If all Haskell packages were visible to these commands, then
+name-based search/install operations would be much slower than they are now. We
+avoided that by keeping all Haskell-related packages in a separate attribute
+set called `haskellPackages`, which the following command will list:
+
+    $ nix-env -f "<nixpkgs>" -qaP -A haskellPackages
+    haskellPackages.a50         a50-0.5
+    haskellPackages.abacate     haskell-abacate-0.0.0.0
+    haskellPackages.abcBridge   haskell-abcBridge-0.12
+    haskellPackages.afv         afv-0.1.1
+    haskellPackages.alex        alex-3.1.4
+    haskellPackages.Allure      Allure-0.4.101.1
+    haskellPackages.alms        alms-0.6.7
+    [... some 8000 entries omitted  ...]
+
+To install any of those packages into your profile, refer to them by their
+attribute path (first column):
+
+    $ nix-env -f "<nixpkgs>" -iA haskellPackages.Allure ...
+
+The attribute path of any Haskell packages corresponds to the name of that
+particular package on Hackage: the package `cabal-install` has the attribute
+`haskellPackages.cabal-install`, and so on. (Actually, this convention causes
+trouble with packages like `3dmodels` and `4Blocks`, because these names are
+invalid identifiers in the Nix language. The issue of how to deal with these
+rare corner cases is currently unresolved.)
+
+Haskell packages who's Nix name (second column) begins with a `haskell-` prefix
+are packages that provide a library whereas packages without that prefix
+provide just executables. Libraries may provide executables too, though: the
+package `haskell-pandoc`, for example, installs both a library and an
+application. You can install and use Haskell executables just like any other
+program in Nixpkgs, but using Haskell libraries for development is a bit
+trickier and we'll address that subject in great detail in section [How to
+create a development environment].
+
+Attribute paths are deterministic inside of Nixpkgs, but the path necessary to
+reach Nixpkgs varies from system to system. We dodged that problem by giving
+`nix-env` an explicit `-f "<nixpkgs>"` parameter, but if you call `nix-env`
+without that flag, then chances are the invocation fails:
+
+    $ nix-env -iA haskellPackages.cabal-install
+    error: attribute ‘haskellPackages’ in selection path
+           ‘haskellPackages.cabal-install’ not found
+
+On NixOS, for example, Nixpkgs does *not* exist in the top-level namespace by
+default. To figure out the proper attribute path, it's easiest to query for the
+path of a well-known Nixpkgs package, i.e.:
+
+    $ nix-env -qaP coreutils
+    nixos.coreutils  coreutils-8.23
+
+If your system responds like that (most NixOS installations will), then the
+attribute path to `haskellPackages` is `nixos.haskellPackages`. Thus, if you
+want to use `nix-env` without giving an explicit `-f` flag, then that's the way
+to do it:
+
+    $ nix-env -qaP -A nixos.haskellPackages
+    $ nix-env -iA nixos.haskellPackages.cabal-install
+
+Our current default compiler is GHC 7.10.x and the `haskellPackages` set
+contains packages built with that particular version. Nixpkgs contains the
+latest major release of every GHC since 6.10.4, however, and there is a whole
+family of package sets available that defines Hackage packages built with each
+of those compilers, too:
+
+    $ nix-env -f "<nixpkgs>" -qaP -A haskell.packages.ghc6123
+    $ nix-env -f "<nixpkgs>" -qaP -A haskell.packages.ghc763
+
+The name `haskellPackages` is really just a synonym for
+`haskell.packages.ghc7102`, because we prefer that package set internally and
+recommend it to our users as their default choice, but ultimately you are free
+to compile your Haskell packages with any GHC version you please. The following
+command displays the complete list of available compilers:
+
+    $ nix-env -f "<nixpkgs>" -qaP -A haskell.compiler
+    haskell.compiler.ghc6104        ghc-6.10.4
+    haskell.compiler.ghc6123        ghc-6.12.3
+    haskell.compiler.ghc704         ghc-7.0.4
+    haskell.compiler.ghc722         ghc-7.2.2
+    haskell.compiler.ghc742         ghc-7.4.2
+    haskell.compiler.ghc763         ghc-7.6.3
+    haskell.compiler.ghc784         ghc-7.8.4
+    haskell.compiler.ghc7102        ghc-7.10.2
+    haskell.compiler.ghcHEAD        ghc-7.11.20150402
+    haskell.compiler.ghcNokinds     ghc-nokinds-7.11.20150704
+    haskell.compiler.ghcjs          ghcjs-0.1.0
+    haskell.compiler.jhc            jhc-0.8.2
+    haskell.compiler.uhc            uhc-1.1.9.0
+
+We have no package sets for `jhc` or `uhc` yet, unfortunately, but for every
+version of GHC listed above, there exists a package set based on that compiler.
+Also, the attributes `haskell.compiler.ghcXYC` and
+`haskell.packages.ghcXYC.ghc` are synonymous for the sake of convenience.
+
+## How to create a development environment
+
+### How to install a compiler
+
+A simple development environment consists of a Haskell compiler and one or both
+of the tools `cabal-install` and `stack`. We saw in section
+[How to install Haskell packages] how you can install those programs into your
+user profile:
+
+    $ nix-env -f "<nixpkgs>" -iA haskellPackages.ghc haskellPackages.cabal-install
+
+Instead of the default package set `haskellPackages`, you can also use the more
+precise name `haskell.compiler.ghc7102`, which has the advantage that it refers
+to the same GHC version regardless of what Nixpkgs considers "default" at any
+given time.
+
+Once you've made those tools available in `$PATH`, it's possible to build
+Hackage packages the same way people without access to Nix do it all the time:
+
+    $ cabal get lens-4.11 && cd lens-4.11
+    $ cabal install -j --dependencies-only
+    $ cabal configure
+    $ cabal build
+
+If you enjoy working with Cabal sandboxes, then that's entirely possible too:
+just execute the command
+
+    $ cabal sandbox init
+
+before installing the required dependencies.
+
+The `nix-shell` utility makes it easy to switch to a different compiler
+version; just enter the Nix shell environment with the command
+
+    $ nix-shell -p haskell.compiler.ghc784
+
+to bring GHC 7.8.4 into `$PATH`. Alternatively, you can use Stack instead of
+`nix-shell` directly to select compiler versions and other build tools
+per-project. It uses `nix-shell` under the hood when Nix support is turned on.
+See [How to build a Haskell project using Stack].
+
+If you're using `cabal-install`, re-running `cabal configure` inside the spawned
+shell switches your build to use that compiler instead. If you're working on
+a project that doesn't depend on any additional system libraries outside of GHC,
+then it's even sufficient to just run the `cabal configure` command inside of
+the shell:
+
+    $ nix-shell -p haskell.compiler.ghc784 --command "cabal configure"
+
+Afterwards, all other commands like `cabal build` work just fine in any shell
+environment, because the configure phase recorded the absolute paths to all
+required tools like GHC in its build configuration inside of the `dist/`
+directory. Please note, however, that `nix-collect-garbage` can break such an
+environment because the Nix store paths created by `nix-shell` aren't "alive"
+anymore once `nix-shell` has terminated. If you find that your Haskell builds
+no longer work after garbage collection, then you'll have to re-run `cabal
+configure` inside of a new `nix-shell` environment.
+
+### How to install a compiler with libraries
+
+GHC expects to find all installed libraries inside of its own `lib` directory.
+This approach works fine on traditional Unix systems, but it doesn't work for
+Nix, because GHC's store path is immutable once it's built. We cannot install
+additional libraries into that location. As a consequence, our copies of GHC
+don't know any packages except their own core libraries, like `base`,
+`containers`, `Cabal`, etc.
+
+We can register additional libraries to GHC, however, using a special build
+function called `ghcWithPackages`. That function expects one argument: a
+function that maps from an attribute set of Haskell packages to a list of
+packages, which determines the libraries known to that particular version of
+GHC. For example, the Nix expression `ghcWithPackages (pkgs: [pkgs.mtl])`
+generates a copy of GHC that has the `mtl` library registered in addition to
+its normal core packages:
+
+    $ nix-shell -p "haskellPackages.ghcWithPackages (pkgs: [pkgs.mtl])"
+
+    [nix-shell:~]$ ghc-pkg list mtl
+    /nix/store/zy79...-ghc-7.10.2/lib/ghc-7.10.2/package.conf.d:
+        mtl-2.2.1
+
+This function allows users to define their own development environment by means
+of an override. After adding the following snippet to `~/.config/nixpkgs/config.nix`,
+
+    {
+      packageOverrides = super: let self = super.pkgs; in
+      {
+        myHaskellEnv = self.haskell.packages.ghc7102.ghcWithPackages
+                         (haskellPackages: with haskellPackages; [
+                           # libraries
+                           arrows async cgi criterion
+                           # tools
+                           cabal-install haskintex
+                         ]);
+      };
+    }
+
+it's possible to install that compiler with `nix-env -f "<nixpkgs>" -iA
+myHaskellEnv`. If you'd like to switch that development environment to a
+different version of GHC, just replace the `ghc7102` bit in the previous
+definition with the appropriate name. Of course, it's also possible to define
+any number of these development environments! (You can't install two of them
+into the same profile at the same time, though, because that would result in
+file conflicts.)
+
+The generated `ghc` program is a wrapper script that re-directs the real
+GHC executable to use a new `lib` directory --- one that we specifically
+constructed to contain all those packages the user requested:
+
+    $ cat $(type -p ghc)
+    #! /nix/store/xlxj...-bash-4.3-p33/bin/bash -e
+    export NIX_GHC=/nix/store/19sm...-ghc-7.10.2/bin/ghc
+    export NIX_GHCPKG=/nix/store/19sm...-ghc-7.10.2/bin/ghc-pkg
+    export NIX_GHC_DOCDIR=/nix/store/19sm...-ghc-7.10.2/share/doc/ghc/html
+    export NIX_GHC_LIBDIR=/nix/store/19sm...-ghc-7.10.2/lib/ghc-7.10.2
+    exec /nix/store/j50p...-ghc-7.10.2/bin/ghc "-B$NIX_GHC_LIBDIR" "$@"
+
+The variables `$NIX_GHC`, `$NIX_GHCPKG`, etc. point to the *new* store path
+`ghcWithPackages` constructed specifically for this environment. The last line
+of the wrapper script then executes the real `ghc`, but passes the path to the
+new `lib` directory using GHC's `-B` flag.
+
+The purpose of those environment variables is to work around an impurity in the
+popular [ghc-paths](http://hackage.haskell.org/package/ghc-paths) library. That
+library promises to give its users access to GHC's installation paths. Only,
+the library can't possible know that path when it's compiled, because the path
+GHC considers its own is determined only much later, when the user configures
+it through `ghcWithPackages`. So we [patched
+ghc-paths](https://github.com/NixOS/nixpkgs/blob/master/pkgs/development/haskell-modules/patches/ghc-paths-nix.patch)
+to return the paths found in those environment variables at run-time rather
+than trying to guess them at compile-time.
+
+To make sure that mechanism works properly all the time, we recommend that you
+set those variables to meaningful values in your shell environment, too, i.e.
+by adding the following code to your `~/.bashrc`:
+
+    if type >/dev/null 2>&1 -p ghc; then
+      eval "$(egrep ^export "$(type -p ghc)")"
+    fi
+
+If you are certain that you'll use only one GHC environment which is located in
+your user profile, then you can use the following code, too, which has the
+advantage that it doesn't contain any paths from the Nix store, i.e. those
+settings always remain valid even if a `nix-env -u` operation updates the GHC
+environment in your profile:
+
+    if [ -e ~/.nix-profile/bin/ghc ]; then
+      export NIX_GHC="$HOME/.nix-profile/bin/ghc"
+      export NIX_GHCPKG="$HOME/.nix-profile/bin/ghc-pkg"
+      export NIX_GHC_DOCDIR="$HOME/.nix-profile/share/doc/ghc/html"
+      export NIX_GHC_LIBDIR="$HOME/.nix-profile/lib/ghc-$($NIX_GHC --numeric-version)"
+    fi
+
+### How to install a compiler with libraries, hoogle and documentation indexes
+
+If you plan to use your environment for interactive programming, not just
+compiling random Haskell code, you might want to replace `ghcWithPackages` in
+all the listings above with `ghcWithHoogle`.
+
+This environment generator not only produces an environment with GHC and all
+the specified libraries, but also generates a `hoogle` and `haddock` indexes
+for all the packages, and provides a wrapper script around `hoogle` binary that
+uses all those things. A precise name for this thing would be
+"`ghcWithPackagesAndHoogleAndDocumentationIndexes`", which is, regrettably, too
+long and scary.
+
+For example, installing the following environment
+
+    {
+      packageOverrides = super: let self = super.pkgs; in
+      {
+        myHaskellEnv = self.haskellPackages.ghcWithHoogle
+                         (haskellPackages: with haskellPackages; [
+                           # libraries
+                           arrows async cgi criterion
+                           # tools
+                           cabal-install haskintex
+                         ]);
+      };
+    }
+
+allows one to browse module documentation index [not too dissimilar to
+this](https://downloads.haskell.org/~ghc/latest/docs/html/libraries/index.html)
+for all the specified packages and their dependencies by directing a browser of
+choice to `~/.nix-profiles/share/doc/hoogle/index.html` (or
+`/run/current-system/sw/share/doc/hoogle/index.html` in case you put it in
+`environment.systemPackages` in NixOS).
+
+After you've marveled enough at that try adding the following to your
+`~/.ghc/ghci.conf`
+
+    :def hoogle \s -> return $ ":! hoogle search -cl --count=15 \"" ++ s ++ "\""
+    :def doc \s -> return $ ":! hoogle search -cl --info \"" ++ s ++ "\""
+
+and test it by typing into `ghci`:
+
+    :hoogle a -> a
+    :doc a -> a
+
+Be sure to note the links to `haddock` files in the output. With any modern and
+properly configured terminal emulator you can just click those links to
+navigate there.
+
+Finally, you can run
+
+    hoogle server -p 8080
+
+and navigate to http://localhost:8080/ for your own local
+[Hoogle](https://www.haskell.org/hoogle/). Note, however, that Firefox and
+possibly other browsers disallow navigation from `http:` to `file:` URIs for
+security reasons, which might be quite an inconvenience. See [this
+page](http://kb.mozillazine.org/Links_to_local_pages_do_not_work) for
+workarounds.
+
+### How to build a Haskell project using Stack
+
+[Stack](http://haskellstack.org) is a popular build tool for Haskell projects.
+It has first-class support for Nix. Stack can optionally use Nix to
+automatically select the right version of GHC and other build tools to build,
+test and execute apps in an existing project downloaded from somewhere on the
+Internet. Pass the `--nix` flag to any `stack` command to do so, e.g.
+
+    $ git clone --recursive http://github.com/yesodweb/wai
+    $ cd wai
+    $ stack --nix build
+
+If you want `stack` to use Nix by default, you can add a `nix` section to the
+`stack.yaml` file, as explained in the [Stack documentation][stack-nix-doc]. For
+example:
+
+    nix:
+      enable: true
+      packages: [pkgconfig zeromq zlib]
+
+The example configuration snippet above tells Stack to create an ad hoc
+environment for `nix-shell` as in the below section, in which the `pkgconfig`,
+`zeromq` and `zlib` packages from Nixpkgs are available. All `stack` commands
+will implicitly be executed inside this ad hoc environment.
+
+Some projects have more sophisticated needs. For examples, some ad hoc
+environments might need to expose Nixpkgs packages compiled in a certain way, or
+with extra environment variables. In these cases, you'll need a `shell` field
+instead of `packages`:
+
+    nix:
+      enable: true
+      shell-file: shell.nix
+
+For more on how to write a `shell.nix` file see the below section. You'll need
+to express a derivation. Note that Nixpkgs ships with a convenience wrapper
+function around `mkDerivation` called `haskell.lib.buildStackProject` to help you
+create this derivation in exactly the way Stack expects. All of the same inputs
+as `mkDerivation` can be provided. For example, to build a Stack project that
+including packages that link against a version of the R library compiled with
+special options turned on:
+
+    with (import <nixpkgs> { });
+
+    let R = pkgs.R.override { enableStrictBarrier = true; };
+    in
+	haskell.lib.buildStackProject {
+      name = "HaskellR";
+	  buildInputs = [ R zeromq zlib ];
+    }
+
+You can select a particular GHC version to compile with by setting the
+`ghc` attribute as an argument to `buildStackProject`. Better yet, let
+Stack choose what GHC version it wants based on the snapshot specified
+in `stack.yaml` (only works with Stack >= 1.1.3):
+
+    {nixpkgs ? import <nixpkgs> { }, ghc ? nixpkgs.ghc}:
+
+    with nixpkgs;
+
+    let R = pkgs.R.override { enableStrictBarrier = true; };
+    in
+    haskell.lib.buildStackProject {
+      name = "HaskellR";
+      buildInputs = [ R zeromq zlib ];
+      inherit ghc;
+    }
+
+[stack-nix-doc]: http://docs.haskellstack.org/en/stable/nix_integration.html
+
+### How to create ad hoc environments for `nix-shell`
+
+The easiest way to create an ad hoc development environment is to run
+`nix-shell` with the appropriate GHC environment given on the command-line:
+
+    nix-shell -p "haskellPackages.ghcWithPackages (pkgs: with pkgs; [mtl pandoc])"
+
+For more sophisticated use-cases, however, it's more convenient to save the
+desired configuration in a file called `shell.nix` that looks like this:
+
+    { nixpkgs ? import <nixpkgs> {}, compiler ? "ghc7102" }:
+    let
+      inherit (nixpkgs) pkgs;
+      ghc = pkgs.haskell.packages.${compiler}.ghcWithPackages (ps: with ps; [
+              monad-par mtl
+            ]);
+    in
+    pkgs.stdenv.mkDerivation {
+      name = "my-haskell-env-0";
+      buildInputs = [ ghc ];
+      shellHook = "eval $(egrep ^export ${ghc}/bin/ghc)";
+    }
+
+Now run `nix-shell` --- or even `nix-shell --pure` --- to enter a shell
+environment that has the appropriate compiler in `$PATH`. If you use `--pure`,
+then add all other packages that your development environment needs into the
+`buildInputs` attribute. If you'd like to switch to a different compiler
+version, then pass an appropriate `compiler` argument to the expression, i.e.
+`nix-shell --argstr compiler ghc784`.
+
+If you need such an environment because you'd like to compile a Hackage package
+outside of Nix --- i.e. because you're hacking on the latest version from Git
+---, then the package set provides suitable nix-shell environments for you
+already! Every Haskell package has an `env` attribute that provides a shell
+environment suitable for compiling that particular package. If you'd like to
+hack the `lens` library, for example, then you just have to check out the
+source code and enter the appropriate environment:
+
+      $ cabal get lens-4.11 && cd lens-4.11
+      Downloading lens-4.11...
+      Unpacking to lens-4.11/
+
+      $ nix-shell "<nixpkgs>" -A haskellPackages.lens.env
+      [nix-shell:/tmp/lens-4.11]$
+
+At point, you can run `cabal configure`, `cabal build`, and all the other
+development commands. Note that you need `cabal-install` installed in your
+`$PATH` already to use it here --- the `nix-shell` environment does not provide
+it.
+
+## How to create Nix builds for your own private Haskell packages
+
+If your own Haskell packages have build instructions for Cabal, then you can
+convert those automatically into build instructions for Nix using the
+`cabal2nix` utility, which you can install into your profile by running
+`nix-env -i cabal2nix`.
+
+### How to build a stand-alone project
+
+For example, let's assume that you're working on a private project called
+`foo`. To generate a Nix build expression for it, change into the project's
+top-level directory and run the command:
+
+    $ cabal2nix . >foo.nix
+
+Then write the following snippet into a file called `default.nix`:
+
+    { nixpkgs ? import <nixpkgs> {}, compiler ? "ghc7102" }:
+    nixpkgs.pkgs.haskell.packages.${compiler}.callPackage ./foo.nix { }
+
+Finally, store the following code in a file called `shell.nix`:
+
+    { nixpkgs ? import <nixpkgs> {}, compiler ? "ghc7102" }:
+    (import ./default.nix { inherit nixpkgs compiler; }).env
+
+At this point, you can run `nix-build` to have Nix compile your project and
+install it into a Nix store path. The local directory will contain a symlink
+called `result` after `nix-build` returns that points into that location. Of
+course, passing the flag `--argstr compiler ghc763` allows switching the build
+to any version of GHC currently supported.
+
+Furthermore, you can call `nix-shell` to enter an interactive development
+environment in which you can use `cabal configure` and `cabal build` to develop
+your code. That environment will automatically contain a proper GHC derivation
+with all the required libraries registered as well as all the system-level
+libraries your package might need.
+
+If your package does not depend on any system-level libraries, then it's
+sufficient to run
+
+    $ nix-shell --command "cabal configure"
+
+once to set up your build. `cabal-install` determines the absolute paths to all
+resources required for the build and writes them into a config file in the
+`dist/` directory. Once that's done, you can run `cabal build` and any other
+command for that project even outside of the `nix-shell` environment. This
+feature is particularly nice for those of us who like to edit their code with
+an IDE, like Emacs' `haskell-mode`, because it's not necessary to start Emacs
+inside of nix-shell just to make it find out the necessary settings for
+building the project; `cabal-install` has already done that for us.
+
+If you want to do some quick-and-dirty hacking and don't want to bother setting
+up a `default.nix` and `shell.nix` file manually, then you can use the
+`--shell` flag offered by `cabal2nix` to have it generate a stand-alone
+`nix-shell` environment for you. With that feature, running
+
+    $ cabal2nix --shell . >shell.nix
+    $ nix-shell --command "cabal configure"
+
+is usually enough to set up a build environment for any given Haskell package.
+You can even use that generated file to run `nix-build`, too:
+
+    $ nix-build shell.nix
+
+### How to build projects that depend on each other
+
+If you have multiple private Haskell packages that depend on each other, then
+you'll have to register those packages in the Nixpkgs set to make them visible
+for the dependency resolution performed by `callPackage`. First of all, change
+into each of your projects top-level directories and generate a `default.nix`
+file with `cabal2nix`:
+
+    $ cd ~/src/foo && cabal2nix . >default.nix
+    $ cd ~/src/bar && cabal2nix . >default.nix
+
+Then edit your `~/.config/nixpkgs/config.nix` file to register those builds in the
+default Haskell package set:
+
+      {
+        packageOverrides = super: let self = super.pkgs; in
+        {
+          haskellPackages = super.haskellPackages.override {
+            overrides = self: super: {
+              foo = self.callPackage ../src/foo {};
+              bar = self.callPackage ../src/bar {};
+            };
+          };
+        };
+      }
+
+Once that's accomplished, `nix-env -f "<nixpkgs>" -qA haskellPackages` will
+show your packages like any other package from Hackage, and you can build them
+
+    $ nix-build "<nixpkgs>" -A haskellPackages.foo
+
+or enter an interactive shell environment suitable for building them:
+
+    $ nix-shell "<nixpkgs>" -A haskellPackages.bar.env
+
+## Miscellaneous Topics
+
+### How to build with profiling enabled
+
+Every Haskell package set takes a function called `overrides` that you can use
+to manipulate the package as much as you please. One useful application of this
+feature is to replace the default `mkDerivation` function with one that enables
+library profiling for all packages. To accomplish that, add configure the
+following snippet in your `~/.config/nixpkgs/config.nix` file:
+
+    {
+      packageOverrides = super: let self = super.pkgs; in
+      {
+        profiledHaskellPackages = self.haskellPackages.override {
+          overrides = self: super: {
+            mkDerivation = args: super.mkDerivation (args // {
+              enableLibraryProfiling = true;
+            });
+          };
+        };
+      };
+    }
+
+Then, replace instances of `haskellPackages` in the `cabal2nix`-generated
+`default.nix` or `shell.nix` files with `profiledHaskellPackages`.
+
+### How to override package versions in a compiler-specific package set
+
+Nixpkgs provides the latest version of
+[`ghc-events`](http://hackage.haskell.org/package/ghc-events), which is 0.4.4.0
+at the time of this writing. This is fine for users of GHC 7.10.x, but GHC
+7.8.4 cannot compile that binary. Now, one way to solve that problem is to
+register an older version of `ghc-events` in the 7.8.x-specific package set.
+The first step is to generate Nix build instructions with `cabal2nix`:
+
+    $ cabal2nix cabal://ghc-events-0.4.3.0 >~/.nixpkgs/ghc-events-0.4.3.0.nix
+
+Then add the override in `~/.config/nixpkgs/config.nix`:
+
+    {
+      packageOverrides = super: let self = super.pkgs; in
+      {
+        haskell = super.haskell // {
+          packages = super.haskell.packages // {
+            ghc784 = super.haskell.packages.ghc784.override {
+              overrides = self: super: {
+                ghc-events = self.callPackage ./ghc-events-0.4.3.0.nix {};
+              };
+            };
+          };
+        };
+      };
+    }
+
+This code is a little crazy, no doubt, but it's necessary because the intuitive
+version
+
+    haskell.packages.ghc784 = super.haskell.packages.ghc784.override {
+      overrides = self: super: {
+        ghc-events = self.callPackage ./ghc-events-0.4.3.0.nix {};
+      };
+    };
+
+doesn't do what we want it to: that code replaces the `haskell` package set in
+Nixpkgs with one that contains only one entry,`packages`, which contains only
+one entry `ghc784`. This override loses the `haskell.compiler` set, and it
+loses the `haskell.packages.ghcXYZ` sets for all compilers but GHC 7.8.4. To
+avoid that problem, we have to perform the convoluted little dance from above,
+iterating over each step in hierarchy.
+
+Once it's accomplished, however, we can install a variant of `ghc-events`
+that's compiled with GHC 7.8.4:
+
+    nix-env -f "<nixpkgs>" -iA haskell.packages.ghc784.ghc-events
+
+Unfortunately, it turns out that this build fails again while executing the
+test suite! Apparently, the release archive on Hackage is missing some data
+files that the test suite requires, so we cannot run it. We accomplish that by
+re-generating the Nix expression with the `--no-check` flag:
+
+    $ cabal2nix --no-check cabal://ghc-events-0.4.3.0 >~/.nixpkgs/ghc-events-0.4.3.0.nix
+
+Now the builds succeeds.
+
+Of course, in the concrete example of `ghc-events` this whole exercise is not
+an ideal solution, because `ghc-events` can analyze the output emitted by any
+version of GHC later than 6.12 regardless of the compiler version that was used
+to build the `ghc-events` executable, so strictly speaking there's no reason to
+prefer one built with GHC 7.8.x in the first place. However, for users who
+cannot use GHC 7.10.x at all for some reason, the approach of downgrading to an
+older version might be useful.
+
+### How to recover from GHC's infamous non-deterministic library ID bug
+
+GHC and distributed build farms don't get along well:
+
+    https://ghc.haskell.org/trac/ghc/ticket/4012
+
+When you see an error like this one
+
+    package foo-0.7.1.0 is broken due to missing package
+    text-1.2.0.4-98506efb1b9ada233bb5c2b2db516d91
+
+then you have to download and re-install `foo` and all its dependents from
+scratch:
+
+    # nix-store -q --referrers /nix/store/*-haskell-text-1.2.0.4 \
+      | xargs -L 1 nix-store --repair-path
+
+If you're using additional Hydra servers other than `hydra.nixos.org`, then it
+might be necessary to purge the local caches that store data from those
+machines to disable these binary channels for the duration of the previous
+command, i.e. by running:
+
+    rm /nix/var/nix/binary-cache-v3.sqlite
+    rm /nix/var/nix/manifests/*
+    rm /nix/var/nix/channel-cache/*
+
+### How to use the Haste Haskell-to-Javascript transpiler
+
+Open a shell with `haste-compiler` and `haste-cabal-install` (you don't actually need
+`node`, but it can be useful to test stuff):
+
+    $ nix-shell -p "haskellPackages.ghcWithPackages (self: with self; [haste-cabal-install haste-compiler])" -p nodejs
+
+You may not need the following step but if `haste-boot` fails to compile all the
+packages it needs, this might do the trick
+
+    $ haste-cabal update
+
+`haste-boot` builds a set of core libraries so that they can be used from Javascript
+transpiled programs:
+
+    $ haste-boot
+
+Transpile and run a "Hello world" program:
+
+    $ echo 'module Main where main = putStrLn "Hello world"' > hello-world.hs
+    $ hastec --onexec hello-world.hs
+    $ node hello-world.js
+    Hello world
+
+### Builds on Darwin fail with `math.h` not found
+
+Users of GHC on Darwin have occasionally reported that builds fail, because the
+compiler complains about a missing include file:
+
+    fatal error: 'math.h' file not found
+
+The issue has been discussed at length in [ticket
+6390](https://github.com/NixOS/nixpkgs/issues/6390), and so far no good
+solution has been proposed. As a work-around, users who run into this problem
+can configure the environment variables
+
+    export NIX_CFLAGS_COMPILE="-idirafter /usr/include"
+    export NIX_CFLAGS_LINK="-L/usr/lib"
+
+in their `~/.bashrc` file to avoid the compiler error.
+
+### Builds using Stack complain about missing system libraries
+
+    --  While building package zlib-0.5.4.2 using:
+      runhaskell -package=Cabal-1.22.4.0 -clear-package-db [... lots of flags ...]
+    Process exited with code: ExitFailure 1
+    Logs have been written to: /home/foo/src/stack-ide/.stack-work/logs/zlib-0.5.4.2.log
+
+    Configuring zlib-0.5.4.2...
+    Setup.hs: Missing dependency on a foreign library:
+    * Missing (or bad) header file: zlib.h
+    This problem can usually be solved by installing the system package that
+    provides this library (you may need the "-dev" version). If the library is
+    already installed but in a non-standard location then you can use the flags
+    --extra-include-dirs= and --extra-lib-dirs= to specify where it is.
+    If the header file does exist, it may contain errors that are caught by the C
+    compiler at the preprocessing stage. In this case you can re-run configure
+    with the verbosity flag -v3 to see the error messages.
+
+When you run the build inside of the nix-shell environment, the system
+is configured to find libz.so without any special flags -- the compiler
+and linker "just know" how to find it. Consequently, Cabal won't record
+any search paths for libz.so in the package description, which means
+that the package works fine inside of nix-shell, but once you leave the
+shell the shared object can no longer be found. That issue is by no
+means specific to Stack: you'll have that problem with any other
+Haskell package that's built inside of nix-shell but run outside of that
+environment.
+
+You can remedy this issue in several ways. The easiest is to add a `nix` section
+to the `stack.yaml` like the following:
+
+    nix:
+      enable: true
+	  packages: [ zlib ]
+
+Stack's Nix support knows to add `${zlib.out}/lib` and `${zlib.dev}/include` as an
+`--extra-lib-dirs` and `extra-include-dirs`, respectively. Alternatively, you
+can achieve the same effect by hand. First of all, run
+
+    $ nix-build --no-out-link "<nixpkgs>" -A zlib
+    /nix/store/alsvwzkiw4b7ip38l4nlfjijdvg3fvzn-zlib-1.2.8
+
+to find out the store path of the system's zlib library. Now, you can
+
+1) add that path (plus a "/lib" suffix) to your $LD_LIBRARY_PATH
+   environment variable to make sure your system linker finds libz.so
+   automatically. It's no pretty solution, but it will work.
+
+2) As a variant of (1), you can also install any number of system
+   libraries into your user's profile (or some other profile) and point
+   $LD_LIBRARY_PATH to that profile instead, so that you don't have to
+   list dozens of those store paths all over the place.
+
+3) The solution I prefer is to call stack with an appropriate
+   --extra-lib-dirs flag like so:
+
+    $ stack --extra-lib-dirs=/nix/store/alsvwzkiw4b7ip38l4nlfjijdvg3fvzn-zlib-1.2.8/lib build
+
+   Typically, you'll need --extra-include-dirs as well. It's possible
+   to add those flag to the project's "stack.yaml" or your user's
+   global "~/.stack/global/stack.yaml" file so that you don't have to
+   specify them manually every time. But again, you're likely better off using
+   Stack's Nix support instead.
+
+   The same thing applies to `cabal configure`, of course, if you're
+   building with `cabal-install` instead of Stack.
+
+### Creating statically linked binaries
+
+There are two levels of static linking. The first option is to configure the
+build with the Cabal flag `--disable-executable-dynamic`. In Nix expressions,
+this can be achieved by setting the attribute:
+
+    enableSharedExecutables = false;
+
+That gives you a binary with statically linked Haskell libraries and
+dynamically linked system libraries.
+
+To link both Haskell libraries and system libraries statically, the additional
+flags `--ghc-option=-optl=-static --ghc-option=-optl=-pthread` need to be used.
+In Nix, this is accomplished with:
+
+    configureFlags = [ "--ghc-option=-optl=-static" "--ghc-option=-optl=-pthread" ];
+
+It's important to realize, however, that most system libraries in Nix are built
+as shared libraries only, i.e. there is just no static library available that
+Cabal could link!
+
+### Building GHC with integer-simple
+
+By default GHC implements the Integer type using the
+[GNU Multiple Precision Arithmetic (GMP) library](https://gmplib.org/).
+The implementation can be found in the
+[integer-gmp](http://hackage.haskell.org/package/integer-gmp) package.
+
+A potential problem with this is that GMP is licensed under the
+[GNU Lesser General Public License (LGPL)](http://www.gnu.org/copyleft/lesser.html),
+a kind of "copyleft" license. According to the terms of the LGPL, paragraph 5,
+you may distribute a program that is designed to be compiled and dynamically
+linked with the library under the terms of your choice (i.e., commercially) but
+if your program incorporates portions of the library, if it is linked
+statically, then your program is a "derivative"--a "work based on the
+library"--and according to paragraph 2, section c, you "must cause the whole of
+the work to be licensed" under the terms of the LGPL (including for free).
+
+The LGPL licensing for GMP is a problem for the overall licensing of binary
+programs compiled with GHC because most distributions (and builds) of GHC use
+static libraries. (Dynamic libraries are currently distributed only for OS X.)
+The LGPL licensing situation may be worse: even though
+[The Glasgow Haskell Compiler License](https://www.haskell.org/ghc/license)
+is essentially a "free software" license (BSD3), according to
+paragraph 2 of the LGPL, GHC must be distributed under the terms of the LGPL!
+
+To work around these problems GHC can be build with a slower but LGPL-free
+alternative implemention for Integer called
+[integer-simple](http://hackage.haskell.org/package/integer-simple).
+
+To get a GHC compiler build with `integer-simple` instead of `integer-gmp` use
+the attribute: `pkgs.haskell.compiler.integer-simple."${ghcVersion}"`.
+For example:
+
+    $ nix-build -E '(import <nixpkgs> {}).pkgs.haskell.compiler.integer-simple.ghc802'
+    ...
+    $ result/bin/ghc-pkg list | grep integer
+        integer-simple-0.1.1.1
+
+The following command displays the complete list of GHC compilers build with `integer-simple`:
+
+    $ nix-env -f "<nixpkgs>" -qaP -A haskell.compiler.integer-simple
+    haskell.compiler.integer-simple.ghc7102  ghc-7.10.2
+    haskell.compiler.integer-simple.ghc7103  ghc-7.10.3
+    haskell.compiler.integer-simple.ghc722   ghc-7.2.2
+    haskell.compiler.integer-simple.ghc742   ghc-7.4.2
+    haskell.compiler.integer-simple.ghc763   ghc-7.6.3
+    haskell.compiler.integer-simple.ghc783   ghc-7.8.3
+    haskell.compiler.integer-simple.ghc784   ghc-7.8.4
+    haskell.compiler.integer-simple.ghc801   ghc-8.0.1
+    haskell.compiler.integer-simple.ghc802   ghc-8.0.2
+    haskell.compiler.integer-simple.ghcHEAD  ghc-8.1.20170106
+
+To get a package set supporting `integer-simple` use the attribute:
+`pkgs.haskell.packages.integer-simple."${ghcVersion}"`. For example
+use the following to get the `scientific` package build with `integer-simple`:
+
+    $ nix-build -A pkgs.haskell.packages.integer-simple.ghc802.scientific
+
+
+## Other resources
+
+- The Youtube video [Nix Loves Haskell](https://www.youtube.com/watch?v=BsBhi_r-OeE)
+  provides an introduction into Haskell NG aimed at beginners. The slides are
+  available at http://cryp.to/nixos-meetup-3-slides.pdf and also -- in a form
+  ready for cut & paste -- at
+  https://github.com/NixOS/cabal2nix/blob/master/doc/nixos-meetup-3-slides.md.
+
+- Another Youtube video is [Escaping Cabal Hell with Nix](https://www.youtube.com/watch?v=mQd3s57n_2Y),
+  which discusses the subject of Haskell development with Nix but also provides
+  a basic introduction to Nix as well, i.e. it's suitable for viewers with
+  almost no prior Nix experience.
+
+- Oliver Charles wrote a very nice [Tutorial how to develop Haskell packages with Nix](http://wiki.ocharles.org.uk/Nix).
+
+- The *Journey into the Haskell NG infrastructure* series of postings
+  describe the new Haskell infrastructure in great detail:
+
+    - [Part 1](http://lists.science.uu.nl/pipermail/nix-dev/2015-January/015591.html)
+      explains the differences between the old and the new code and gives
+      instructions how to migrate to the new setup.
+
+    - [Part 2](http://lists.science.uu.nl/pipermail/nix-dev/2015-January/015608.html)
+      looks in-depth at how to tweak and configure your setup by means of
+      overrides.
+
+    - [Part 3](http://lists.science.uu.nl/pipermail/nix-dev/2015-April/016912.html)
+      describes the infrastructure that keeps the Haskell package set in Nixpkgs
+      up-to-date.
--- a/doc/languages-frameworks/haskell.section.md
+++ b/doc/languages-frameworks/haskell.section.md
@@ -1,955 +0,0 @@
---
-title: User's Guide for Haskell in Nixpkgs
-author: Peter Simons
-date: 2015-06-01
---
-# User's Guide to the Haskell Infrastructure
-
-
-## How to install Haskell packages
-
-Nixpkgs distributes build instructions for all Haskell packages registered on
-[Hackage](http://hackage.haskell.org/), but strangely enough normal Nix package
-lookups don't seem to discover any of them, except for the default version of ghc, cabal-install, and stack:
-```
-$ nix-env -i alex
-error: selector ‘alex’ matches no derivations
-$ nix-env -qa ghc
-ghc-7.10.2
-```
-
-The Haskell package set is not registered in the top-level namespace because it
-is *huge*. If all Haskell packages were visible to these commands, then
-name-based search/install operations would be much slower than they are now. We
-avoided that by keeping all Haskell-related packages in a separate attribute
-set called `haskellPackages`, which the following command will list:
-```
-$ nix-env -f "<nixpkgs>" -qaP -A haskellPackages
-haskellPackages.a50         a50-0.5
-haskellPackages.abacate     haskell-abacate-0.0.0.0
-haskellPackages.abcBridge   haskell-abcBridge-0.12
-haskellPackages.afv         afv-0.1.1
-haskellPackages.alex        alex-3.1.4
-haskellPackages.Allure      Allure-0.4.101.1
-haskellPackages.alms        alms-0.6.7
-[... some 8000 entries omitted  ...]
-```
-
-To install any of those packages into your profile, refer to them by their
-attribute path (first column):
-```shell
-nix-env -f "<nixpkgs>" -iA haskellPackages.Allure ...
-```
-
-The attribute path of any Haskell packages corresponds to the name of that
-particular package on Hackage: the package `cabal-install` has the attribute
-`haskellPackages.cabal-install`, and so on. (Actually, this convention causes
-trouble with packages like `3dmodels` and `4Blocks`, because these names are
-invalid identifiers in the Nix language. The issue of how to deal with these
-rare corner cases is currently unresolved.)
-
-Haskell packages whose Nix name (second column) begins with a `haskell-` prefix
-are packages that provide a library whereas packages without that prefix
-provide just executables. Libraries may provide executables too, though: the
-package `haskell-pandoc`, for example, installs both a library and an
-application. You can install and use Haskell executables just like any other
-program in Nixpkgs, but using Haskell libraries for development is a bit
-trickier and we'll address that subject in great detail in section [How to
-create a development environment].
-
-Attribute paths are deterministic inside of Nixpkgs, but the path necessary to
-reach Nixpkgs varies from system to system. We dodged that problem by giving
-`nix-env` an explicit `-f "<nixpkgs>"` parameter, but if you call `nix-env`
-without that flag, then chances are the invocation fails:
-```
-$ nix-env -iA haskellPackages.cabal-install
-error: attribute ‘haskellPackages’ in selection path
-       ‘haskellPackages.cabal-install’ not found
-```
-
-On NixOS, for example, Nixpkgs does *not* exist in the top-level namespace by
-default. To figure out the proper attribute path, it's easiest to query for the
-path of a well-known Nixpkgs package, i.e.:
-```
-$ nix-env -qaP coreutils
-nixos.coreutils  coreutils-8.23
-```
-
-If your system responds like that (most NixOS installations will), then the
-attribute path to `haskellPackages` is `nixos.haskellPackages`. Thus, if you
-want to use `nix-env` without giving an explicit `-f` flag, then that's the way
-to do it:
-```shell
-nix-env -qaP -A nixos.haskellPackages
-nix-env -iA nixos.haskellPackages.cabal-install
-```
-
-Our current default compiler is GHC 7.10.x and the `haskellPackages` set
-contains packages built with that particular version. Nixpkgs contains the
-latest major release of every GHC since 6.10.4, however, and there is a whole
-family of package sets available that defines Hackage packages built with each
-of those compilers, too:
-```shell
-nix-env -f "<nixpkgs>" -qaP -A haskell.packages.ghc6123
-nix-env -f "<nixpkgs>" -qaP -A haskell.packages.ghc763
-```
-
-The name `haskellPackages` is really just a synonym for
-`haskell.packages.ghc7102`, because we prefer that package set internally and
-recommend it to our users as their default choice, but ultimately you are free
-to compile your Haskell packages with any GHC version you please. The following
-command displays the complete list of available compilers:
-```
-$ nix-env -f "<nixpkgs>" -qaP -A haskell.compiler
-haskell.compiler.ghc6104        ghc-6.10.4
-haskell.compiler.ghc6123        ghc-6.12.3
-haskell.compiler.ghc704         ghc-7.0.4
-haskell.compiler.ghc722         ghc-7.2.2
-haskell.compiler.ghc742         ghc-7.4.2
-haskell.compiler.ghc763         ghc-7.6.3
-haskell.compiler.ghc784         ghc-7.8.4
-haskell.compiler.ghc7102        ghc-7.10.2
-haskell.compiler.ghcHEAD        ghc-7.11.20150402
-haskell.compiler.ghcNokinds     ghc-nokinds-7.11.20150704
-haskell.compiler.ghcjs          ghcjs-0.1.0
-haskell.compiler.jhc            jhc-0.8.2
-haskell.compiler.uhc            uhc-1.1.9.0
-```
-
-We have no package sets for `jhc` or `uhc` yet, unfortunately, but for every
-version of GHC listed above, there exists a package set based on that compiler.
-Also, the attributes `haskell.compiler.ghcXYC` and
-`haskell.packages.ghcXYC.ghc` are synonymous for the sake of convenience.
-
-## How to create a development environment
-
-### How to install a compiler
-
-A simple development environment consists of a Haskell compiler and one or both
-of the tools `cabal-install` and `stack`. We saw in section
-[How to install Haskell packages] how you can install those programs into your
-user profile:
-```shell
-nix-env -f "<nixpkgs>" -iA haskellPackages.ghc haskellPackages.cabal-install
-```
-
-Instead of the default package set `haskellPackages`, you can also use the more
-precise name `haskell.compiler.ghc7102`, which has the advantage that it refers
-to the same GHC version regardless of what Nixpkgs considers "default" at any
-given time.
-
-Once you've made those tools available in `$PATH`, it's possible to build
-Hackage packages the same way people without access to Nix do it all the time:
-```shell
-cabal get lens-4.11 && cd lens-4.11
-cabal install -j --dependencies-only
-cabal configure
-cabal build
-```
-
-If you enjoy working with Cabal sandboxes, then that's entirely possible too:
-just execute the command
-```shell
-cabal sandbox init
-```
-before installing the required dependencies.
-
-The `nix-shell` utility makes it easy to switch to a different compiler
-version; just enter the Nix shell environment with the command
-```shell
-nix-shell -p haskell.compiler.ghc784
-```
-to bring GHC 7.8.4 into `$PATH`. Alternatively, you can use Stack instead of
-`nix-shell` directly to select compiler versions and other build tools
-per-project. It uses `nix-shell` under the hood when Nix support is turned on.
-See [How to build a Haskell project using Stack].
-
-If you're using `cabal-install`, re-running `cabal configure` inside the spawned
-shell switches your build to use that compiler instead. If you're working on
-a project that doesn't depend on any additional system libraries outside of GHC,
-then it's even sufficient to just run the `cabal configure` command inside of
-the shell:
-```shell
-nix-shell -p haskell.compiler.ghc784 --command "cabal configure"
-```
-
-Afterwards, all other commands like `cabal build` work just fine in any shell
-environment, because the configure phase recorded the absolute paths to all
-required tools like GHC in its build configuration inside of the `dist/`
-directory. Please note, however, that `nix-collect-garbage` can break such an
-environment because the Nix store paths created by `nix-shell` aren't "alive"
-anymore once `nix-shell` has terminated. If you find that your Haskell builds
-no longer work after garbage collection, then you'll have to re-run `cabal
-configure` inside of a new `nix-shell` environment.
-
-### How to install a compiler with libraries
-
-GHC expects to find all installed libraries inside of its own `lib` directory.
-This approach works fine on traditional Unix systems, but it doesn't work for
-Nix, because GHC's store path is immutable once it's built. We cannot install
-additional libraries into that location. As a consequence, our copies of GHC
-don't know any packages except their own core libraries, like `base`,
-`containers`, `Cabal`, etc.
-
-We can register additional libraries to GHC, however, using a special build
-function called `ghcWithPackages`. That function expects one argument: a
-function that maps from an attribute set of Haskell packages to a list of
-packages, which determines the libraries known to that particular version of
-GHC. For example, the Nix expression `ghcWithPackages (pkgs: [pkgs.mtl])`
-generates a copy of GHC that has the `mtl` library registered in addition to
-its normal core packages:
-```
-$ nix-shell -p "haskellPackages.ghcWithPackages (pkgs: [pkgs.mtl])"
-
-[nix-shell:~]$ ghc-pkg list mtl
-/nix/store/zy79...-ghc-7.10.2/lib/ghc-7.10.2/package.conf.d:
-    mtl-2.2.1
-```
-
-This function allows users to define their own development environment by means
-of an override. After adding the following snippet to `~/.config/nixpkgs/config.nix`,
-```nix
-{
-  packageOverrides = super: let self = super.pkgs; in
-  {
-    myHaskellEnv = self.haskell.packages.ghc7102.ghcWithPackages
-                     (haskellPackages: with haskellPackages; [
-                       # libraries
-                       arrows async cgi criterion
-                       # tools
-                       cabal-install haskintex
-                     ]);
-  };
-}
-```
-it's possible to install that compiler with `nix-env -f "<nixpkgs>" -iA
-myHaskellEnv`. If you'd like to switch that development environment to a
-different version of GHC, just replace the `ghc7102` bit in the previous
-definition with the appropriate name. Of course, it's also possible to define
-any number of these development environments! (You can't install two of them
-into the same profile at the same time, though, because that would result in
-file conflicts.)
-
-The generated `ghc` program is a wrapper script that re-directs the real
-GHC executable to use a new `lib` directory --- one that we specifically
-constructed to contain all those packages the user requested:
-```
-$ cat $(type -p ghc)
-#! /nix/store/xlxj...-bash-4.3-p33/bin/bash -e
-export NIX_GHC=/nix/store/19sm...-ghc-7.10.2/bin/ghc
-export NIX_GHCPKG=/nix/store/19sm...-ghc-7.10.2/bin/ghc-pkg
-export NIX_GHC_DOCDIR=/nix/store/19sm...-ghc-7.10.2/share/doc/ghc/html
-export NIX_GHC_LIBDIR=/nix/store/19sm...-ghc-7.10.2/lib/ghc-7.10.2
-exec /nix/store/j50p...-ghc-7.10.2/bin/ghc "-B$NIX_GHC_LIBDIR" "$@"
-```
-
-The variables `$NIX_GHC`, `$NIX_GHCPKG`, etc. point to the *new* store path
-`ghcWithPackages` constructed specifically for this environment. The last line
-of the wrapper script then executes the real `ghc`, but passes the path to the
-new `lib` directory using GHC's `-B` flag.
-
-The purpose of those environment variables is to work around an impurity in the
-popular [ghc-paths](http://hackage.haskell.org/package/ghc-paths) library. That
-library promises to give its users access to GHC's installation paths. Only,
-the library can't possible know that path when it's compiled, because the path
-GHC considers its own is determined only much later, when the user configures
-it through `ghcWithPackages`. So we [patched
-ghc-paths](https://github.com/NixOS/nixpkgs/blob/master/pkgs/development/haskell-modules/patches/ghc-paths-nix.patch)
-to return the paths found in those environment variables at run-time rather
-than trying to guess them at compile-time.
-
-To make sure that mechanism works properly all the time, we recommend that you
-set those variables to meaningful values in your shell environment, too, i.e.
-by adding the following code to your `~/.bashrc`:
-```bash
-if type >/dev/null 2>&1 -p ghc; then
-  eval "$(egrep ^export "$(type -p ghc)")"
-fi
-```
-
-If you are certain that you'll use only one GHC environment which is located in
-your user profile, then you can use the following code, too, which has the
-advantage that it doesn't contain any paths from the Nix store, i.e. those
-settings always remain valid even if a `nix-env -u` operation updates the GHC
-environment in your profile:
-```bash
-if [ -e ~/.nix-profile/bin/ghc ]; then
-  export NIX_GHC="$HOME/.nix-profile/bin/ghc"
-  export NIX_GHCPKG="$HOME/.nix-profile/bin/ghc-pkg"
-  export NIX_GHC_DOCDIR="$HOME/.nix-profile/share/doc/ghc/html"
-  export NIX_GHC_LIBDIR="$HOME/.nix-profile/lib/ghc-$($NIX_GHC --numeric-version)"
-fi
-```
-
-### How to install a compiler with libraries, hoogle and documentation indexes
-
-If you plan to use your environment for interactive programming, not just
-compiling random Haskell code, you might want to replace `ghcWithPackages` in
-all the listings above with `ghcWithHoogle`.
-
-This environment generator not only produces an environment with GHC and all
-the specified libraries, but also generates a `hoogle` and `haddock` indexes
-for all the packages, and provides a wrapper script around `hoogle` binary that
-uses all those things. A precise name for this thing would be
-"`ghcWithPackagesAndHoogleAndDocumentationIndexes`", which is, regrettably, too
-long and scary.
-
-For example, installing the following environment
-```nix
-{
-  packageOverrides = super: let self = super.pkgs; in
-  {
-    myHaskellEnv = self.haskellPackages.ghcWithHoogle
-                     (haskellPackages: with haskellPackages; [
-                       # libraries
-                       arrows async cgi criterion
-                       # tools
-                       cabal-install haskintex
-                     ]);
-  };
-}
-```
-allows one to browse module documentation index [not too dissimilar to
-this](https://downloads.haskell.org/~ghc/latest/docs/html/libraries/index.html)
-for all the specified packages and their dependencies by directing a browser of
-choice to `~/.nix-profiles/share/doc/hoogle/index.html` (or
-`/run/current-system/sw/share/doc/hoogle/index.html` in case you put it in
-`environment.systemPackages` in NixOS).
-
-After you've marveled enough at that try adding the following to your
-`~/.ghc/ghci.conf`
-```
-:def hoogle \s -> return $ ":! hoogle search -cl --count=15 \"" ++ s ++ "\""
-:def doc \s -> return $ ":! hoogle search -cl --info \"" ++ s ++ "\""
-```
-and test it by typing into `ghci`:
-```
-:hoogle a -> a
-:doc a -> a
-```
-
-Be sure to note the links to `haddock` files in the output. With any modern and
-properly configured terminal emulator you can just click those links to
-navigate there.
-
-Finally, you can run
-```shell
-hoogle server -p 8080 --local
-```
-and navigate to http://localhost:8080/ for your own local
-[Hoogle](https://www.haskell.org/hoogle/).
-
-### How to build a Haskell project using Stack
-
-[Stack](http://haskellstack.org) is a popular build tool for Haskell projects.
-It has first-class support for Nix. Stack can optionally use Nix to
-automatically select the right version of GHC and other build tools to build,
-test and execute apps in an existing project downloaded from somewhere on the
-Internet. Pass the `--nix` flag to any `stack` command to do so, e.g.
-```shell
-git clone --recursive http://github.com/yesodweb/wai
-cd wai
-stack --nix build
-```
-
-If you want `stack` to use Nix by default, you can add a `nix` section to the
-`stack.yaml` file, as explained in the [Stack documentation][stack-nix-doc]. For
-example:
-```yaml
-nix:
-  enable: true
-  packages: [pkgconfig zeromq zlib]
-```
-
-The example configuration snippet above tells Stack to create an ad hoc
-environment for `nix-shell` as in the below section, in which the `pkgconfig`,
-`zeromq` and `zlib` packages from Nixpkgs are available. All `stack` commands
-will implicitly be executed inside this ad hoc environment.
-
-Some projects have more sophisticated needs. For examples, some ad hoc
-environments might need to expose Nixpkgs packages compiled in a certain way, or
-with extra environment variables. In these cases, you'll need a `shell` field
-instead of `packages`:
-```yaml
-nix:
-  enable: true
-  shell-file: shell.nix
-```
-
-For more on how to write a `shell.nix` file see the below section. You'll need
-to express a derivation. Note that Nixpkgs ships with a convenience wrapper
-function around `mkDerivation` called `haskell.lib.buildStackProject` to help you
-create this derivation in exactly the way Stack expects. All of the same inputs
-as `mkDerivation` can be provided. For example, to build a Stack project that
-including packages that link against a version of the R library compiled with
-special options turned on:
-```nix
-with (import <nixpkgs> { });
-
-let R = pkgs.R.override { enableStrictBarrier = true; };
-in
-haskell.lib.buildStackProject {
-  name = "HaskellR";
-  buildInputs = [ R zeromq zlib ];
-}
-```
-
-You can select a particular GHC version to compile with by setting the
-`ghc` attribute as an argument to `buildStackProject`. Better yet, let
-Stack choose what GHC version it wants based on the snapshot specified
-in `stack.yaml` (only works with Stack >= 1.1.3):
-```nix
-{nixpkgs ? import <nixpkgs> { }, ghc ? nixpkgs.ghc}:
-
-with nixpkgs;
-
-let R = pkgs.R.override { enableStrictBarrier = true; };
-in
-haskell.lib.buildStackProject {
-  name = "HaskellR";
-  buildInputs = [ R zeromq zlib ];
-  inherit ghc;
-}
-```
-
-[stack-nix-doc]: http://docs.haskellstack.org/en/stable/nix_integration.html
-
-### How to create ad hoc environments for `nix-shell`
-
-The easiest way to create an ad hoc development environment is to run
-`nix-shell` with the appropriate GHC environment given on the command-line:
-```shell
-nix-shell -p "haskellPackages.ghcWithPackages (pkgs: with pkgs; [mtl pandoc])"
-```
-
-For more sophisticated use-cases, however, it's more convenient to save the
-desired configuration in a file called `shell.nix` that looks like this:
-```nix
-{ nixpkgs ? import <nixpkgs> {}, compiler ? "ghc7102" }:
-let
-  inherit (nixpkgs) pkgs;
-  ghc = pkgs.haskell.packages.${compiler}.ghcWithPackages (ps: with ps; [
-          monad-par mtl
-        ]);
-in
-pkgs.stdenv.mkDerivation {
-  name = "my-haskell-env-0";
-  buildInputs = [ ghc ];
-  shellHook = "eval $(egrep ^export ${ghc}/bin/ghc)";
-}
-```
-
-Now run `nix-shell` --- or even `nix-shell --pure` --- to enter a shell
-environment that has the appropriate compiler in `$PATH`. If you use `--pure`,
-then add all other packages that your development environment needs into the
-`buildInputs` attribute. If you'd like to switch to a different compiler
-version, then pass an appropriate `compiler` argument to the expression, i.e.
-`nix-shell --argstr compiler ghc784`.
-
-If you need such an environment because you'd like to compile a Hackage package
-outside of Nix --- i.e. because you're hacking on the latest version from Git
---, then the package set provides suitable nix-shell environments for you
-already! Every Haskell package has an `env` attribute that provides a shell
-environment suitable for compiling that particular package. If you'd like to
-hack the `lens` library, for example, then you just have to check out the
-source code and enter the appropriate environment:
-```
-$ cabal get lens-4.11 && cd lens-4.11
-Downloading lens-4.11...
-Unpacking to lens-4.11/
-
-$ nix-shell "<nixpkgs>" -A haskellPackages.lens.env
-[nix-shell:/tmp/lens-4.11]$
-```
-
-At point, you can run `cabal configure`, `cabal build`, and all the other
-development commands. Note that you need `cabal-install` installed in your
-`$PATH` already to use it here --- the `nix-shell` environment does not provide
-it.
-
-## How to create Nix builds for your own private Haskell packages
-
-If your own Haskell packages have build instructions for Cabal, then you can
-convert those automatically into build instructions for Nix using the
-`cabal2nix` utility, which you can install into your profile by running
-`nix-env -i cabal2nix`.
-
-### How to build a stand-alone project
-
-For example, let's assume that you're working on a private project called
-`foo`. To generate a Nix build expression for it, change into the project's
-top-level directory and run the command:
-```shell
-cabal2nix . > foo.nix
-```
-Then write the following snippet into a file called `default.nix`:
-```nix
-{ nixpkgs ? import <nixpkgs> {}, compiler ? "ghc7102" }:
-nixpkgs.pkgs.haskell.packages.${compiler}.callPackage ./foo.nix { }
-```
-
-Finally, store the following code in a file called `shell.nix`:
-```nix
-{ nixpkgs ? import <nixpkgs> {}, compiler ? "ghc7102" }:
-(import ./default.nix { inherit nixpkgs compiler; }).env
-```
-
-At this point, you can run `nix-build` to have Nix compile your project and
-install it into a Nix store path. The local directory will contain a symlink
-called `result` after `nix-build` returns that points into that location. Of
-course, passing the flag `--argstr compiler ghc763` allows switching the build
-to any version of GHC currently supported.
-
-Furthermore, you can call `nix-shell` to enter an interactive development
-environment in which you can use `cabal configure` and `cabal build` to develop
-your code. That environment will automatically contain a proper GHC derivation
-with all the required libraries registered as well as all the system-level
-libraries your package might need.
-
-If your package does not depend on any system-level libraries, then it's
-sufficient to run
-```shell
-nix-shell --command "cabal configure"
-```
-once to set up your build. `cabal-install` determines the absolute paths to all
-resources required for the build and writes them into a config file in the
-`dist/` directory. Once that's done, you can run `cabal build` and any other
-command for that project even outside of the `nix-shell` environment. This
-feature is particularly nice for those of us who like to edit their code with
-an IDE, like Emacs' `haskell-mode`, because it's not necessary to start Emacs
-inside of nix-shell just to make it find out the necessary settings for
-building the project; `cabal-install` has already done that for us.
-
-If you want to do some quick-and-dirty hacking and don't want to bother setting
-up a `default.nix` and `shell.nix` file manually, then you can use the
-`--shell` flag offered by `cabal2nix` to have it generate a stand-alone
-`nix-shell` environment for you. With that feature, running
-```shell
-cabal2nix --shell . > shell.nix
-nix-shell --command "cabal configure"
-```
-is usually enough to set up a build environment for any given Haskell package.
-You can even use that generated file to run `nix-build`, too:
-```shell
-nix-build shell.nix
-```
-
-### How to build projects that depend on each other
-
-If you have multiple private Haskell packages that depend on each other, then
-you'll have to register those packages in the Nixpkgs set to make them visible
-for the dependency resolution performed by `callPackage`. First of all, change
-into each of your projects top-level directories and generate a `default.nix`
-file with `cabal2nix`:
-```shell
-cd ~/src/foo && cabal2nix . > default.nix
-cd ~/src/bar && cabal2nix . > default.nix
-```
-Then edit your `~/.config/nixpkgs/config.nix` file to register those builds in the
-default Haskell package set:
-```nix
-{
-  packageOverrides = super: let self = super.pkgs; in
-  {
-    haskellPackages = super.haskellPackages.override {
-      overrides = self: super: {
-        foo = self.callPackage ../src/foo {};
-        bar = self.callPackage ../src/bar {};
-      };
-    };
-  };
-}
-```
-Once that's accomplished, `nix-env -f "<nixpkgs>" -qA haskellPackages` will
-show your packages like any other package from Hackage, and you can build them
-```shell
-nix-build "<nixpkgs>" -A haskellPackages.foo
-```
-or enter an interactive shell environment suitable for building them:
-```shell
-nix-shell "<nixpkgs>" -A haskellPackages.bar.env
-```
-
-## Miscellaneous Topics
-
-### How to build with profiling enabled
-
-Every Haskell package set takes a function called `overrides` that you can use
-to manipulate the package as much as you please. One useful application of this
-feature is to replace the default `mkDerivation` function with one that enables
-library profiling for all packages. To accomplish that add the following
-snippet to your `~/.config/nixpkgs/config.nix` file:
-```nix
-{
-  packageOverrides = super: let self = super.pkgs; in
-  {
-    profiledHaskellPackages = self.haskellPackages.override {
-      overrides = self: super: {
-        mkDerivation = args: super.mkDerivation (args // {
-          enableLibraryProfiling = true;
-        });
-      };
-    };
-  };
-}
-```
-Then, replace instances of `haskellPackages` in the `cabal2nix`-generated
-`default.nix` or `shell.nix` files with `profiledHaskellPackages`.
-
-### How to override package versions in a compiler-specific package set
-
-Nixpkgs provides the latest version of
-[`ghc-events`](http://hackage.haskell.org/package/ghc-events), which is 0.4.4.0
-at the time of this writing. This is fine for users of GHC 7.10.x, but GHC
-7.8.4 cannot compile that binary. Now, one way to solve that problem is to
-register an older version of `ghc-events` in the 7.8.x-specific package set.
-The first step is to generate Nix build instructions with `cabal2nix`:
-```shell
-cabal2nix cabal://ghc-events-0.4.3.0 > ~/.nixpkgs/ghc-events-0.4.3.0.nix
-```
-Then add the override in `~/.config/nixpkgs/config.nix`:
-```nix
-{
-  packageOverrides = super: let self = super.pkgs; in
-  {
-    haskell = super.haskell // {
-      packages = super.haskell.packages // {
-        ghc784 = super.haskell.packages.ghc784.override {
-          overrides = self: super: {
-            ghc-events = self.callPackage ./ghc-events-0.4.3.0.nix {};
-          };
-        };
-      };
-    };
-  };
-}
-```
-
-This code is a little crazy, no doubt, but it's necessary because the intuitive
-version
-```nix
-{ # ...
-
-  haskell.packages.ghc784 = super.haskell.packages.ghc784.override {
-    overrides = self: super: {
-      ghc-events = self.callPackage ./ghc-events-0.4.3.0.nix {};
-    };
-  };
-}
-```
-doesn't do what we want it to: that code replaces the `haskell` package set in
-Nixpkgs with one that contains only one entry,`packages`, which contains only
-one entry `ghc784`. This override loses the `haskell.compiler` set, and it
-loses the `haskell.packages.ghcXYZ` sets for all compilers but GHC 7.8.4. To
-avoid that problem, we have to perform the convoluted little dance from above,
-iterating over each step in hierarchy.
-
-Once it's accomplished, however, we can install a variant of `ghc-events`
-that's compiled with GHC 7.8.4:
-```shell
-nix-env -f "<nixpkgs>" -iA haskell.packages.ghc784.ghc-events
-```
-Unfortunately, it turns out that this build fails again while executing the
-test suite! Apparently, the release archive on Hackage is missing some data
-files that the test suite requires, so we cannot run it. We accomplish that by
-re-generating the Nix expression with the `--no-check` flag:
-```shell
-cabal2nix --no-check cabal://ghc-events-0.4.3.0 > ~/.nixpkgs/ghc-events-0.4.3.0.nix
-```
-Now the builds succeeds.
-
-Of course, in the concrete example of `ghc-events` this whole exercise is not
-an ideal solution, because `ghc-events` can analyze the output emitted by any
-version of GHC later than 6.12 regardless of the compiler version that was used
-to build the `ghc-events` executable, so strictly speaking there's no reason to
-prefer one built with GHC 7.8.x in the first place. However, for users who
-cannot use GHC 7.10.x at all for some reason, the approach of downgrading to an
-older version might be useful.
-
-### How to recover from GHC's infamous non-deterministic library ID bug
-
-GHC and distributed build farms don't get along well:
-
-  - https://ghc.haskell.org/trac/ghc/ticket/4012
-
-When you see an error like this one
-```
-package foo-0.7.1.0 is broken due to missing package
-text-1.2.0.4-98506efb1b9ada233bb5c2b2db516d91
-```
-then you have to download and re-install `foo` and all its dependents from
-scratch:
-```shell
-nix-store -q --referrers /nix/store/*-haskell-text-1.2.0.4 \
-  | xargs -L 1 nix-store --repair-path
-```
-
-If you're using additional Hydra servers other than `hydra.nixos.org`, then it
-might be necessary to purge the local caches that store data from those
-machines to disable these binary channels for the duration of the previous
-command, i.e. by running:
-```shell
-rm /nix/var/nix/binary-cache-v3.sqlite
-rm /nix/var/nix/manifests/*
-rm /nix/var/nix/channel-cache/*
-```
-
-### Builds on Darwin fail with `math.h` not found
-
-Users of GHC on Darwin have occasionally reported that builds fail, because the
-compiler complains about a missing include file:
-```
-fatal error: 'math.h' file not found
-```
-The issue has been discussed at length in [ticket
-6390](https://github.com/NixOS/nixpkgs/issues/6390), and so far no good
-solution has been proposed. As a work-around, users who run into this problem
-can configure the environment variables
-```shell
-export NIX_CFLAGS_COMPILE="-idirafter /usr/include"
-export NIX_CFLAGS_LINK="-L/usr/lib"
-```
-in their `~/.bashrc` file to avoid the compiler error.
-
-### Builds using Stack complain about missing system libraries
-
-```
--  While building package zlib-0.5.4.2 using:
-  runhaskell -package=Cabal-1.22.4.0 -clear-package-db [... lots of flags ...]
-Process exited with code: ExitFailure 1
-Logs have been written to: /home/foo/src/stack-ide/.stack-work/logs/zlib-0.5.4.2.log
-
-Configuring zlib-0.5.4.2...
-Setup.hs: Missing dependency on a foreign library:
-* Missing (or bad) header file: zlib.h
-This problem can usually be solved by installing the system package that
-provides this library (you may need the "-dev" version). If the library is
-already installed but in a non-standard location then you can use the flags
--extra-include-dirs= and --extra-lib-dirs= to specify where it is.
-If the header file does exist, it may contain errors that are caught by the C
-compiler at the preprocessing stage. In this case you can re-run configure
-with the verbosity flag -v3 to see the error messages.
-```
-
-When you run the build inside of the nix-shell environment, the system
-is configured to find `libz.so` without any special flags -- the compiler
-and linker "just know" how to find it. Consequently, Cabal won't record
-any search paths for `libz.so` in the package description, which means
-that the package works fine inside of nix-shell, but once you leave the
-shell the shared object can no longer be found. That issue is by no
-means specific to Stack: you'll have that problem with any other
-Haskell package that's built inside of nix-shell but run outside of that
-environment.
-
-You can remedy this issue in several ways. The easiest is to add a `nix` section
-to the `stack.yaml` like the following:
-```yaml
-nix:
-  enable: true
-  packages: [ zlib ]
-```
-
-Stack's Nix support knows to add `${zlib.out}/lib` and `${zlib.dev}/include`
-as an `--extra-lib-dirs` and `extra-include-dirs`, respectively.
-Alternatively, you can achieve the same effect by hand. First of all, run
-```
-$ nix-build --no-out-link "<nixpkgs>" -A zlib
-/nix/store/alsvwzkiw4b7ip38l4nlfjijdvg3fvzn-zlib-1.2.8
-```
-to find out the store path of the system's zlib library. Now, you can
-
-  1. add that path (plus a "/lib" suffix) to your `$LD_LIBRARY_PATH`
-    environment variable to make sure your system linker finds `libz.so`
-    automatically. It's no pretty solution, but it will work.
-
-  2. As a variant of (1), you can also install any number of system
-    libraries into your user's profile (or some other profile) and point
-    `$LD_LIBRARY_PATH` to that profile instead, so that you don't have to
-    list dozens of those store paths all over the place.
-
-  3. The solution I prefer is to call stack with an appropriate
-    --extra-lib-dirs flag like so:
-    ```shell
-    stack --extra-lib-dirs=/nix/store/alsvwzkiw4b7ip38l4nlfjijdvg3fvzn-zlib-1.2.8/lib build
-    ```
-
-Typically, you'll need `--extra-include-dirs` as well. It's possible
-to add those flag to the project's `stack.yaml` or your user's
-global `~/.stack/global/stack.yaml` file so that you don't have to
-specify them manually every time. But again, you're likely better off
-using Stack's Nix support instead.
-
-The same thing applies to `cabal configure`, of course, if you're
-building with `cabal-install` instead of Stack.
-
-### Creating statically linked binaries
-
-There are two levels of static linking. The first option is to configure the
-build with the Cabal flag `--disable-executable-dynamic`. In Nix expressions,
-this can be achieved by setting the attribute:
-```
-enableSharedExecutables = false;
-```
-That gives you a binary with statically linked Haskell libraries and
-dynamically linked system libraries.
-
-To link both Haskell libraries and system libraries statically, the additional
-flags `--ghc-option=-optl=-static --ghc-option=-optl=-pthread` need to be used.
-In Nix, this is accomplished with:
-```
-configureFlags = [ "--ghc-option=-optl=-static" "--ghc-option=-optl=-pthread" ];
-```
-
-It's important to realize, however, that most system libraries in Nix are
-built as shared libraries only, i.e. there is just no static library
-available that Cabal could link!
-
-### Building GHC with integer-simple
-
-By default GHC implements the Integer type using the
-[GNU Multiple Precision Arithmetic (GMP) library](https://gmplib.org/).
-The implementation can be found in the
-[integer-gmp](http://hackage.haskell.org/package/integer-gmp) package.
-
-A potential problem with this is that GMP is licensed under the
-[GNU Lesser General Public License (LGPL)](http://www.gnu.org/copyleft/lesser.html),
-a kind of "copyleft" license. According to the terms of the LGPL, paragraph 5,
-you may distribute a program that is designed to be compiled and dynamically
-linked with the library under the terms of your choice (i.e., commercially) but
-if your program incorporates portions of the library, if it is linked
-statically, then your program is a "derivative"--a "work based on the
-library"--and according to paragraph 2, section c, you "must cause the whole of
-the work to be licensed" under the terms of the LGPL (including for free).
-
-The LGPL licensing for GMP is a problem for the overall licensing of binary
-programs compiled with GHC because most distributions (and builds) of GHC use
-static libraries. (Dynamic libraries are currently distributed only for macOS.)
-The LGPL licensing situation may be worse: even though
-[The Glasgow Haskell Compiler License](https://www.haskell.org/ghc/license)
-is essentially a "free software" license (BSD3), according to
-paragraph 2 of the LGPL, GHC must be distributed under the terms of the LGPL!
-
-To work around these problems GHC can be build with a slower but LGPL-free
-alternative implemention for Integer called
-[integer-simple](http://hackage.haskell.org/package/integer-simple).
-
-To get a GHC compiler build with `integer-simple` instead of `integer-gmp` use
-the attribute: `haskell.compiler.integer-simple."${ghcVersion}"`.
-For example:
-```
-$ nix-build -E '(import <nixpkgs> {}).haskell.compiler.integer-simple.ghc802'
-...
-$ result/bin/ghc-pkg list | grep integer
-    integer-simple-0.1.1.1
-```
-The following command displays the complete list of GHC compilers build with `integer-simple`:
-```
-$ nix-env -f "<nixpkgs>" -qaP -A haskell.compiler.integer-simple
-haskell.compiler.integer-simple.ghc7102  ghc-7.10.2
-haskell.compiler.integer-simple.ghc7103  ghc-7.10.3
-haskell.compiler.integer-simple.ghc722   ghc-7.2.2
-haskell.compiler.integer-simple.ghc742   ghc-7.4.2
-haskell.compiler.integer-simple.ghc783   ghc-7.8.3
-haskell.compiler.integer-simple.ghc784   ghc-7.8.4
-haskell.compiler.integer-simple.ghc801   ghc-8.0.1
-haskell.compiler.integer-simple.ghc802   ghc-8.0.2
-haskell.compiler.integer-simple.ghcHEAD  ghc-8.1.20170106
-```
-
-To get a package set supporting `integer-simple` use the attribute:
-`haskell.packages.integer-simple."${ghcVersion}"`. For example
-use the following to get the `scientific` package build with `integer-simple`:
-```shell
-nix-build -A haskell.packages.integer-simple.ghc802.scientific
-```
-
-### Quality assurance
-
-The `haskell.lib` library includes a number of functions for checking for
-various imperfections in Haskell packages. It's useful to apply these functions
-to your own Haskell packages and integrate that in a Continuous Integration
-server like [hydra](https://nixos.org/hydra/) to assure your packages maintain a
-minimum level of quality. This section discusses some of these functions.
-
-#### failOnAllWarnings
-
-Applying `haskell.lib.failOnAllWarnings` to a Haskell package enables the
-`-Wall` and `-Werror` GHC options to turn all warnings into build failures.
-
-#### buildStrictly
-
-Applying `haskell.lib.buildStrictly` to a Haskell package calls
-`failOnAllWarnings` on the given package to turn all warnings into build
-failures. Additionally the source of your package is gotten from first invoking
-`cabal sdist` to ensure all needed files are listed in the Cabal file.
-
-#### checkUnusedPackages
-
-Applying `haskell.lib.checkUnusedPackages` to a Haskell package invokes
-the [packunused](http://hackage.haskell.org/package/packunused) tool on the
-package. `packunused` complains when it finds packages listed as build-depends
-in the Cabal file which are redundant. For example:
-
-```
-$ nix-build -E 'let pkgs = import <nixpkgs> {}; in pkgs.haskell.lib.checkUnusedPackages {} pkgs.haskellPackages.scientific'
-these derivations will be built:
-  /nix/store/3lc51cxj2j57y3zfpq5i69qbzjpvyci1-scientific-0.3.5.1.drv
-...
-detected package components
-~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
- - library
- - testsuite(s): test-scientific
- - benchmark(s): bench-scientific*
-
-(component names suffixed with '*' are not configured to be built)
-
-library
-~~~~~~~
-
-The following package dependencies seem redundant:
-
- - ghc-prim-0.5.0.0
-
-testsuite(test-scientific)
-~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-no redundant packages dependencies found
-
-builder for ‘/nix/store/3lc51cxj2j57y3zfpq5i69qbzjpvyci1-scientific-0.3.5.1.drv’ failed with exit code 1
-error: build of ‘/nix/store/3lc51cxj2j57y3zfpq5i69qbzjpvyci1-scientific-0.3.5.1.drv’ failed
-```
-
-As you can see, `packunused` finds out that although the testsuite component has
-no redundant dependencies the library component of `scientific-0.3.5.1` depends
-on `ghc-prim` which is unused in the library.
-
-## Other resources
-
-  - The Youtube video [Nix Loves Haskell](https://www.youtube.com/watch?v=BsBhi_r-OeE)
-    provides an introduction into Haskell NG aimed at beginners. The slides are
-    available at http://cryp.to/nixos-meetup-3-slides.pdf and also -- in a form
-    ready for cut & paste -- at
-    https://github.com/NixOS/cabal2nix/blob/master/doc/nixos-meetup-3-slides.md.
-
-  - Another Youtube video is [Escaping Cabal Hell with Nix](https://www.youtube.com/watch?v=mQd3s57n_2Y),
-    which discusses the subject of Haskell development with Nix but also provides
-    a basic introduction to Nix as well, i.e. it's suitable for viewers with
-    almost no prior Nix experience.
-
-  - Oliver Charles wrote a very nice [Tutorial how to develop Haskell packages with Nix](http://wiki.ocharles.org.uk/Nix).
-
-  - The *Journey into the Haskell NG infrastructure* series of postings
-    describe the new Haskell infrastructure in great detail:
-
-      - [Part 1](https://nixos.org/nix-dev/2015-January/015591.html)
-        explains the differences between the old and the new code and gives
-        instructions how to migrate to the new setup.
-
-      - [Part 2](https://nixos.org/nix-dev/2015-January/015608.html)
-        looks in-depth at how to tweak and configure your setup by means of
-        overrides.
-
-      - [Part 3](https://nixos.org/nix-dev/2015-April/016912.html)
-        describes the infrastructure that keeps the Haskell package set in Nixpkgs
-        up-to-date.
--- a/doc/languages-frameworks/idris.section.md
+++ b/doc/languages-frameworks/idris.section.md
@@ -1,39 +0,0 @@
-Idris packages
-==============
-
-This directory contains build rules for idris packages. In addition,
-it contains several functions to build and compose those packages.
-Everything is exposed to the user via the `idrisPackages` attribute.
-
-callPackage
------------
-
-This is like the normal nixpkgs callPackage function, specialized to
-idris packages.
-
-builtins
---------
-
-This is a list of all of the libraries that come packaged with Idris
-itself.
-
-build-idris-package
--------------------
-
-A function to build an idris package. Its sole argument is a set like
-you might pass to `stdenv.mkDerivation`, except `build-idris-package`
-sets several attributes for you. See `build-idris-package.nix` for
-details.
-
-build-builtin-package
----------------------
-
-A version of `build-idris-package` specialized to builtin libraries.
-Mostly for internal use.
-
-with-packages
-------------
-
-Bundle idris together with a list of packages. Because idris currently
-only supports a single directory in its library path, you must include
-all desired libraries here, including `prelude` and `base`.
--- a/doc/languages-frameworks/index.xml
+++ b/doc/languages-frameworks/index.xml
@@ -17,18 +17,18 @@ such as Perl or Haskell.  These are described in this chapter.</para>
 <xi:include href="bower.xml" />
 <xi:include href="coq.xml" />
 <xi:include href="go.xml" />
-<xi:include href="haskell.section.xml" />
-<xi:include href="idris.section.xml" />
+<xi:include href="haskell.xml" />
+<xi:include href="idris.xml" /> <!-- generated from ../../pkgs/development/idris-modules/README.md  -->
 <xi:include href="java.xml" />
 <xi:include href="lua.xml" />
-<xi:include href="node.section.xml" />
+<xi:include href="node.xml" /> <!-- generated from ../../pkgs/development/node-packages/README.md  -->
 <xi:include href="perl.xml" />
-<xi:include href="python.section.xml" />
+<xi:include href="python.xml" />
 <xi:include href="qt.xml" />
-<xi:include href="r.section.xml" />
+<xi:include href="r.xml" /> <!-- generated from ../../pkgs/development/r-modules/README.md  -->
 <xi:include href="ruby.xml" />
-<xi:include href="rust.section.xml" />
 <xi:include href="texlive.xml" />
-<xi:include href="vim.section.xml" />
+<xi:include href="vim.xml" />
+

 </chapter>
--- a/doc/languages-frameworks/node.section.md
+++ b/doc/languages-frameworks/node.section.md
@@ -1,51 +0,0 @@
-Node.js packages
-================
-The `pkgs/development/node-packages` folder contains a generated collection of
-[NPM packages](https://npmjs.com/) that can be installed with the Nix package
-manager.
-
-As a rule of thumb, the package set should only provide *end user* software
-packages, such as command-line utilities. Libraries should only be added to the
-package set if there is a non-NPM package that requires it.
-
-When it is desired to use NPM libraries in a development project, use the
-`node2nix` generator directly on the `package.json` configuration file of the
-project.
-
-The package set also provides support for multiple Node.js versions. The policy
-is that a new package should be added to the collection for the latest stable LTS
-release (which is currently 6.x), unless there is an explicit reason to support
-a different release.
-
-If your package uses native addons, you need to examine what kind of native
-build system it uses. Here are some examples:
-
-* `node-gyp`
-* `node-gyp-builder`
-* `node-pre-gyp`
-
-After you have identified the correct system, you need to override your package
-expression while adding in build system as a build input. For example, `dat`
-requires `node-gyp-build`, so we override its expression in `default-v6.nix`:
-
-```nix
-dat = nodePackages.dat.override (oldAttrs: {
-  buildInputs = oldAttrs.buildInputs ++ [ nodePackages.node-gyp-build ];
-});
-```
-
-To add a package from NPM to nixpkgs:
-
- 1. Modify `pkgs/development/node-packages/node-packages-v6.json` to add, update
-    or remove package entries. (Or `pkgs/development/node-packages/node-packages-v4.json`
-    for packages depending on Node.js 4.x)
- 2. Run the script: `(cd pkgs/development/node-packages && ./generate.sh)`.
- 3. Build your new package to test your changes:
-    `cd /path/to/nixpkgs && nix-build -A nodePackages.<new-or-updated-package>`.
-    To build against a specific Node.js version (e.g. 4.x):
-    `nix-build -A nodePackages_4_x.<new-or-updated-package>`
- 4. Add and commit all modified and generated files.
-
-For more information about the generation process, consult the
-[README.md](https://github.com/svanderburg/node2nix) file of the `node2nix`
-tool.
--- a/doc/languages-frameworks/python.md
+++ b/doc/languages-frameworks/python.md
@@ -0,0 +1,867 @@
+# Python
+
+## User Guide
+
+Several versions of Python are available on Nix as well as a high amount of
+packages. The default interpreter is CPython 3.5.
+
+### Using Python
+
+#### Installing Python and packages
+
+It is important to make a distinction between Python packages that are
+used as libraries, and applications that are written in Python.
+
+Applications on Nix are installed typically into your user
+profile imperatively using `nix-env -i`, and on NixOS declaratively by adding the
+package name to `environment.systemPackages` in `/etc/nixos/configuration.nix`.
+Dependencies such as libraries are automatically installed and should not be
+installed explicitly.
+
+The same goes for Python applications and libraries. Python applications can be
+installed in your profile, but Python libraries you would like to use to develop
+cannot. If you do install libraries in your profile, then you will end up with
+import errors.
+
+#### Python environments using `nix-shell`
+
+The recommended method for creating Python environments for development is with
+`nix-shell`. Executing
+
+```sh
+$ nix-shell -p python35Packages.numpy python35Packages.toolz
+```
+
+opens a Nix shell which has available the requested packages and dependencies.
+Now you can launch the Python interpreter (which is itself a dependency)
+
+```sh
+[nix-shell:~] python3
+```
+
+If the packages were not available yet in the Nix store, Nix would download or
+build them automatically. A convenient option with `nix-shell` is the `--run`
+option, with which you can execute a command in the `nix-shell`. Let's say we
+want the above environment and directly run the Python interpreter
+
+```sh
+$ nix-shell -p python35Packages.numpy python35Packages.toolz --run "python3"
+```
+
+This way you can use the `--run` option also to directly run a script
+
+```sh
+$ nix-shell -p python35Packages.numpy python35Packages.toolz --run "python3 myscript.py"
+```
+
+In fact, for this specific use case there is a more convenient method. You can
+add a [shebang](https://en.wikipedia.org/wiki/Shebang_(Unix)) to your script
+specifying which dependencies Nix shell needs. With the following shebang, you
+can use `nix-shell myscript.py` and it will make available all dependencies and
+run the script in the `python3` shell.
+
+```py
+#! /usr/bin/env nix-shell
+#! nix-shell -i python3 -p python3Packages.numpy
+
+import numpy
+
+print(numpy.__version__)
+```
+
+Likely you do not want to type your dependencies each and every time. What you
+can do is write a simple Nix expression which sets up an environment for you,
+requiring you only to type `nix-shell`. Say we want to have Python 3.5, `numpy`
+and `toolz`, like before, in an environment. With a `shell.nix` file
+containing
+
+```nix
+with import <nixpkgs> {};
+
+(pkgs.python35.withPackages (ps: [ps.numpy ps.toolz])).env
+```
+executing `nix-shell` gives you again a Nix shell from which you can run Python.
+
+What's happening here?
+
+1. We begin with importing the Nix Packages collections. `import <nixpkgs>` import the `<nixpkgs>` function, `{}` calls it and the `with` statement brings all attributes of `nixpkgs` in the local scope. Therefore we can now use `pkgs`.
+2. Then we create a Python 3.5 environment with the `withPackages` function.
+3. The `withPackages` function expects us to provide a function as an argument that takes the set of all python packages and returns a list of packages to include in the environment. Here, we select the packages `numpy` and `toolz` from the package set.
+4. And finally, for in interactive use we return the environment by using the `env` attribute.
+
+### Developing with Python
+
+
+Now that you know how to get a working Python environment on Nix, it is time to go forward and start actually developing with Python.
+We will first have a look at how Python packages are packaged on Nix. Then, we will look how you can use development mode with your code.
+
+#### Python packaging on Nix
+
+On Nix all packages are built by functions. The main function in Nix for building Python packages is [`buildPythonPackage`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/development/interpreters/python/build-python-package.nix).
+Let's see how we would build the `toolz` package. According to [`python-packages.nix`](https://raw.githubusercontent.com/NixOS/nixpkgs/master/pkgs/top-level/python-packages.nix) `toolz` is build using
+
+```nix
+toolz = buildPythonPackage rec{
+  name = "toolz-${version}";
+  version = "0.7.4";
+
+  src = pkgs.fetchurl{
+    url = "mirror://pypi/t/toolz/toolz-${version}.tar.gz";
+    sha256 = "43c2c9e5e7a16b6c88ba3088a9bfc82f7db8e13378be7c78d6c14a5f8ed05afd";
+  };
+
+  meta = {
+    homepage = "http://github.com/pytoolz/toolz/";
+    description = "List processing tools and functional utilities";
+    license = licenses.bsd3;
+    maintainers = with maintainers; [ fridh ];
+  };
+};
+```
+
+What happens here? The function `buildPythonPackage` is called and as argument
+it accepts a set. In this case the set is a recursive set ([`rec`](http://nixos.org/nix/manual/#sec-constructs)).
+One of the arguments is the name of the package, which consists of a basename
+(generally following the name on PyPi) and a version. Another argument, `src`
+specifies the source, which in this case is fetched from an url. `fetchurl` not
+only downloads the target file, but also validates its hash. Furthermore, we
+specify some (optional) [meta information](http://nixos.org/nixpkgs/manual/#chap-meta).
+
+The output of the function is a derivation, which is an attribute with the name
+`toolz` of the set `pythonPackages`. Actually, sets are created for all interpreter versions,
+so `python27Packages`, `python34Packages`, `python35Packages` and `pypyPackages`.
+
+The above example works when you're directly working on
+`pkgs/top-level/python-packages.nix` in the Nixpkgs repository. Often though,
+you will want to test a Nix expression outside of the Nixpkgs tree. If you
+create a `shell.nix` file with the following contents
+
+```nix
+with import <nixpkgs> {};
+
+pkgs.python35Packages.buildPythonPackage rec {
+  name = "toolz-${version}";
+  version = "0.8.0";
+
+  src = pkgs.fetchurl{
+    url = "mirror://pypi/t/toolz/toolz-${version}.tar.gz";
+    sha256 = "e8451af61face57b7c5d09e71c0d27b8005f001ead56e9fdf470417e5cc6d479";
+  };
+
+  doCheck = false;
+
+  meta = {
+    homepage = "http://github.com/pytoolz/toolz/";
+    description = "List processing tools and functional utilities";
+    license = licenses.bsd3;
+    maintainers = with maintainers; [ fridh ];
+  };
+}
+```
+
+and then execute `nix-shell` will result in an environment in which you can use
+Python 3.5 and the `toolz` package. As you can see we had to explicitly mention
+for which Python version we want to build a package.
+
+The above example considered only a single package. Generally you will want to use multiple packages.
+If we create a `shell.nix` file with the following contents
+
+```nix
+with import <nixpkgs> {};
+
+( let
+    toolz = pkgs.python35Packages.buildPythonPackage rec {
+      name = "toolz-${version}";
+      version = "0.8.0";
+
+      src = pkgs.fetchurl{
+        url = "mirror://pypi/t/toolz/toolz-${version}.tar.gz";
+        sha256 = "e8451af61face57b7c5d09e71c0d27b8005f001ead56e9fdf470417e5cc6d479";
+      };
+
+      doCheck = false;
+
+      meta = {
+        homepage = "http://github.com/pytoolz/toolz/";
+        description = "List processing tools and functional utilities";
+      };
+    };
+
+  in pkgs.python35.withPackages (ps: [ps.numpy toolz])
+).env
+```
+
+and again execute `nix-shell`, then we get a Python 3.5 environment with our
+locally defined package as well as `numpy` which is build according to the
+definition in Nixpkgs. What did we do here? Well, we took the Nix expression
+that we used earlier to build a Python environment, and said that we wanted to
+include our own version of `toolz`. To introduce our own package in the scope of
+`withPackages` we used a
+[`let`](http://nixos.org/nix/manual/#sec-constructs) expression.
+You can see that we used `ps.numpy` to select numpy from the nixpkgs package set (`ps`).
+But we do not take `toolz` from the nixpkgs package set this time.
+Instead, `toolz` will resolve to our local definition that we introduced with `let`.
+
+### Handling dependencies
+
+Our example, `toolz`, doesn't have any dependencies on other Python
+packages or system libraries. According to the manual,  `buildPythonPackage`
+uses the arguments `buildInputs` and `propagatedBuildInputs` to specify dependencies. If something is
+exclusively a build-time dependency, then the dependency should be included as a
+`buildInput`, but if it is (also) a runtime dependency, then it should be added
+to `propagatedBuildInputs`. Test dependencies are considered build-time dependencies.
+
+The following example shows which arguments are given to `buildPythonPackage` in
+order to build [`datashape`](https://github.com/blaze/datashape).
+
+```nix
+datashape = buildPythonPackage rec {
+  name = "datashape-${version}";
+  version = "0.4.7";
+
+  src = pkgs.fetchurl {
+    url = "mirror://pypi/D/DataShape/${name}.tar.gz";
+    sha256 = "14b2ef766d4c9652ab813182e866f493475e65e558bed0822e38bf07bba1a278";
+  };
+
+  buildInputs = with self; [ pytest ];
+  propagatedBuildInputs = with self; [ numpy multipledispatch dateutil ];
+
+  meta = {
+    homepage = https://github.com/ContinuumIO/datashape;
+    description = "A data description language";
+    license = licenses.bsd2;
+    maintainers = with maintainers; [ fridh ];
+  };
+};
+```
+
+We can see several runtime dependencies, `numpy`, `multipledispatch`, and
+`dateutil`. Furthermore, we have one `buildInput`, i.e. `pytest`. `pytest` is a
+test runner and is only used during the `checkPhase` and is therefore not added
+to `propagatedBuildInputs`.
+
+In the previous case we had only dependencies on other Python packages to consider.
+Occasionally you have also system libraries to consider. E.g., `lxml` provides
+Python bindings to `libxml2` and `libxslt`. These libraries are only required
+when building the bindings and are therefore added as `buildInputs`.
+
+```nix
+lxml = buildPythonPackage rec {
+  name = "lxml-3.4.4";
+
+  src = pkgs.fetchurl {
+    url = "mirror://pypi/l/lxml/${name}.tar.gz";
+    sha256 = "16a0fa97hym9ysdk3rmqz32xdjqmy4w34ld3rm3jf5viqjx65lxk";
+  };
+
+  buildInputs = with self; [ pkgs.libxml2 pkgs.libxslt ];
+
+  meta = {
+    description = "Pythonic binding for the libxml2 and libxslt libraries";
+    homepage = http://lxml.de;
+    license = licenses.bsd3;
+    maintainers = with maintainers; [ sjourdois ];
+  };
+};
+```
+
+In this example `lxml` and Nix are able to work out exactly where the relevant
+files of the dependencies are. This is not always the case.
+
+The example below shows bindings to The Fastest Fourier Transform in the West, commonly known as
+FFTW. On Nix we have separate packages of FFTW for the different types of floats
+(`"single"`, `"double"`, `"long-double"`). The bindings need all three types,
+and therefore we add all three as `buildInputs`. The bindings don't expect to
+find each of them in a different folder, and therefore we have to set `LDFLAGS`
+and `CFLAGS`.
+
+```nix
+pyfftw = buildPythonPackage rec {
+  name = "pyfftw-${version}";
+  version = "0.9.2";
+
+  src = pkgs.fetchurl {
+    url = "mirror://pypi/p/pyFFTW/pyFFTW-${version}.tar.gz";
+    sha256 = "f6bbb6afa93085409ab24885a1a3cdb8909f095a142f4d49e346f2bd1b789074";
+  };
+
+  buildInputs = [ pkgs.fftw pkgs.fftwFloat pkgs.fftwLongDouble];
+
+  propagatedBuildInputs = with self; [ numpy scipy ];
+
+  # Tests cannot import pyfftw. pyfftw works fine though.
+  doCheck = false;
+
+  LDFLAGS="-L${pkgs.fftw.dev}/lib -L${pkgs.fftwFloat.out}/lib -L${pkgs.fftwLongDouble.out}/lib"
+  CFLAGS="-I${pkgs.fftw.dev}/include -I${pkgs.fftwFloat.dev}/include -I${pkgs.fftwLongDouble.dev}/include"
+  '';
+
+  meta = {
+    description = "A pythonic wrapper around FFTW, the FFT library, presenting a unified interface for all the supported transforms";
+    homepage = http://hgomersall.github.com/pyFFTW/;
+    license = with licenses; [ bsd2 bsd3 ];
+    maintainer = with maintainers; [ fridh ];
+  };
+};
+```
+Note also the line `doCheck = false;`, we explicitly disabled running the test-suite.
+
+
+#### Develop local package
+
+As a Python developer you're likely aware of [development mode](http://setuptools.readthedocs.io/en/latest/setuptools.html#development-mode) (`python setup.py develop`);
+instead of installing the package this command creates a special link to the project code.
+That way, you can run updated code without having to reinstall after each and every change you make.
+Development mode is also available. Let's see how you can use it.
+
+In the previous Nix expression the source was fetched from an url. We can also refer to a local source instead using
+
+```nix
+src = ./path/to/source/tree;
+```
+
+If we create a `shell.nix` file which calls `buildPythonPackage`, and if `src`
+is a local source, and if the local source has a `setup.py`, then development
+mode is activated.
+
+In the following example we create a simple environment that
+has a Python 3.5 version of our package in it, as well as its dependencies and
+other packages we like to have in the environment, all specified with `propagatedBuildInputs`.
+Indeed, we can just add any package we like to have in our environment to `propagatedBuildInputs`.
+
+```nix
+with import <nixpkgs>;
+with pkgs.python35Packages;
+
+buildPythonPackage rec {
+  name = "mypackage";
+  src = ./path/to/package/source;
+  propagatedBuildInputs = [ pytest numpy pkgs.libsndfile ];
+};
+```
+
+It is important to note that due to how development mode is implemented on Nix it is not possible to have multiple packages simultaneously in development mode.
+
+
+### Organising your packages
+
+So far we discussed how you can use Python on Nix, and how you can develop with
+it. We've looked at how you write expressions to package Python packages, and we
+looked at how you can create environments in which specified packages are
+available.
+
+At some point you'll likely have multiple packages which you would
+like to be able to use in different projects. In order to minimise unnecessary
+duplication we now look at how you can maintain yourself a repository with your
+own packages. The important functions here are `import` and `callPackage`.
+
+### Including a derivation using `callPackage`
+
+Earlier we created a Python environment using `withPackages`, and included the
+`toolz` package via a `let` expression.
+Let's split the package definition from the environment definition.
+
+We first create a function that builds `toolz` in `~/path/to/toolz/release.nix`
+
+```nix
+{ pkgs, buildPythonPackage }:
+
+buildPythonPackage rec {
+  name = "toolz-${version}";
+  version = "0.7.4";
+
+  src = pkgs.fetchurl{
+    url = "mirror://pypi/t/toolz/toolz-${version}.tar.gz";
+    sha256 = "43c2c9e5e7a16b6c88ba3088a9bfc82f7db8e13378be7c78d6c14a5f8ed05afd";
+  };
+
+  meta = {
+    homepage = "http://github.com/pytoolz/toolz/";
+    description = "List processing tools and functional utilities";
+    license = licenses.bsd3;
+    maintainers = with maintainers; [ fridh ];
+  };
+};
+```
+
+It takes two arguments, `pkgs` and `buildPythonPackage`.
+We now call this function using `callPackage` in the definition of our environment
+
+```nix
+with import <nixpkgs> {};
+
+( let
+    toolz = pkgs.callPackage ~/path/to/toolz/release.nix { pkgs=pkgs; buildPythonPackage=pkgs.python35Packages.buildPythonPackage; };
+  in pkgs.python35.withPackages (ps: [ ps.numpy toolz ])
+).env
+```
+
+Important to remember is that the Python version for which the package is made
+depends on the `python` derivation that is passed to `buildPythonPackage`. Nix
+tries to automatically pass arguments when possible, which is why generally you
+don't explicitly define which `python` derivation should be used. In the above
+example we use `buildPythonPackage` that is part of the set `python35Packages`,
+and in this case the `python35` interpreter is automatically used.
+
+
+
+## Reference
+
+### Interpreters
+
+Versions 2.6, 2.7, 3.3, 3.4 and 3.5 of the CPython interpreter are available as respectively
+`python26`, `python27`, `python33`, `python34` and `python35`. The PyPy interpreter
+is available as `pypy`. The aliases `python2` and `python3` correspond to respectively `python27` and
+`python35`. The default interpreter, `python`, maps to `python2`.
+The Nix expressions for the interpreters can be found in
+`pkgs/development/interpreters/python`.
+
+All packages depending on any Python interpreter get appended
+`out/{python.sitePackages}` to `$PYTHONPATH` if such directory
+exists.
+
+#### Missing `tkinter` module standard library
+
+To reduce closure size the `Tkinter`/`tkinter` is available as a separate package, `pythonPackages.tkinter`.
+
+#### Attributes on interpreters packages
+
+Each interpreter has the following attributes:
+
+- `libPrefix`. Name of the folder in `${python}/lib/` for corresponding interpreter.
+- `interpreter`. Alias for `${python}/bin/${executable}`.
+- `buildEnv`. Function to build python interpreter environments with extra packages bundled together. See section *python.buildEnv function* for usage and documentation.
+- `withPackages`. Simpler interface to `buildEnv`. See section *python.withPackages function* for usage and documentation.
+- `sitePackages`. Alias for `lib/${libPrefix}/site-packages`.
+- `executable`. Name of the interpreter executable, e.g. `python3.4`.
+- `pkgs`. Set of Python packages for that specific interpreter. The package set can be modified by overriding the interpreter and passing `packageOverrides`.
+
+### Building packages and applications
+
+Python libraries and applications that use `setuptools` or
+`distutils` are typically build with respectively the `buildPythonPackage` and
+`buildPythonApplication` functions. These two functions also support installing a `wheel`.
+
+All Python packages reside in `pkgs/top-level/python-packages.nix` and all
+applications elsewhere. In case a package is used as both a library and an application,
+then the package should be in `pkgs/top-level/python-packages.nix` since only those packages are made
+available for all interpreter versions. The preferred location for library expressions is in
+`pkgs/development/python-modules`. It is important that these packages are
+called from `pkgs/top-level/python-packages.nix` and not elsewhere, to guarantee
+the right version of the package is built.
+
+Based on the packages defined in `pkgs/top-level/python-packages.nix` an
+attribute set is created for each available Python interpreter. The available
+sets are
+
+* `pkgs.python26Packages`
+* `pkgs.python27Packages`
+* `pkgs.python33Packages`
+* `pkgs.python34Packages`
+* `pkgs.python35Packages`
+* `pkgs.pypyPackages`
+
+and the aliases
+
+* `pkgs.python2Packages` pointing to `pkgs.python27Packages`
+* `pkgs.python3Packages` pointing to `pkgs.python35Packages`
+* `pkgs.pythonPackages` pointing to `pkgs.python2Packages`
+
+#### `buildPythonPackage` function
+
+The `buildPythonPackage` function is implemented in
+`pkgs/development/interpreters/python/build-python-package.nix`
+
+The following is an example:
+
+    twisted = buildPythonPackage {
+      name = "twisted-8.1.0";
+
+      src = pkgs.fetchurl {
+        url = http://tmrc.mit.edu/mirror/twisted/Twisted/8.1/Twisted-8.1.0.tar.bz2;
+        sha256 = "0q25zbr4xzknaghha72mq57kh53qw1bf8csgp63pm9sfi72qhirl";
+      };
+
+      propagatedBuildInputs = [ self.ZopeInterface ];
+
+      meta = {
+        homepage = http://twistedmatrix.com/;
+        description = "Twisted, an event-driven networking engine written in Python";
+        license = stdenv.lib.licenses.mit; };
+      };
+
+The `buildPythonPackage` mainly does four things:
+
+* In the `buildPhase`, it calls `${python.interpreter} setup.py bdist_wheel` to
+  build a wheel binary zipfile.
+* In the `installPhase`, it installs the wheel file using `pip install *.whl`.
+* In the `postFixup` phase, the `wrapPythonPrograms` bash function is called to
+  wrap all programs in the `$out/bin/*` directory to include `$PATH`
+  environment variable and add dependent libraries to script's `sys.path`.
+* In the `installCheck` phase, `${python.interpreter} setup.py test` is ran.
+
+As in Perl, dependencies on other Python packages can be specified in the
+`buildInputs` and `propagatedBuildInputs` attributes.  If something is
+exclusively a build-time dependency, use `buildInputs`; if it’s (also) a runtime
+dependency, use `propagatedBuildInputs`.
+
+By default tests are run because `doCheck = true`. Test dependencies, like
+e.g. the test runner, should be added to `buildInputs`.
+
+By default `meta.platforms` is set to the same value
+as the interpreter unless overriden otherwise.
+
+##### `buildPythonPackage` parameters
+
+All parameters from `mkDerivation` function are still supported.
+
+* `namePrefix`: Prepended text to `${name}` parameter. Defaults to `"python3.3-"` for Python 3.3, etc. Set it to `""` if you're packaging an application or a command line tool.
+* `disabled`: If `true`, package is not build for particular python interpreter version. Grep around `pkgs/top-level/python-packages.nix` for examples.
+* `setupPyBuildFlags`: List of flags passed to `setup.py build_ext` command.
+* `pythonPath`: List of packages to be added into `$PYTHONPATH`. Packages in `pythonPath` are not propagated (contrary to `propagatedBuildInputs`).
+* `preShellHook`: Hook to execute commands before `shellHook`.
+* `postShellHook`: Hook to execute commands after `shellHook`.
+* `makeWrapperArgs`: A list of strings. Arguments to be passed to `makeWrapper`, which wraps generated binaries. By default, the arguments to `makeWrapper` set `PATH` and `PYTHONPATH` environment variables before calling the binary. Additional arguments here can allow a developer to set environment variables which will be available when the binary is run. For example, `makeWrapperArgs = ["--set FOO BAR" "--set BAZ QUX"]`.
+* `installFlags`: A list of strings. Arguments to be passed to `pip install`. To pass options to `python setup.py install`, use `--install-option`. E.g., `installFlags=["--install-option='--cpp_implementation'"].
+* `format`: Format of the source. Valid options are `setuptools` (default), `flit`, `wheel`, and `other`. `setuptools` is for when the source has a `setup.py` and `setuptools` is used to build a wheel, `flit`, in case `flit` should be used to build a wheel, and `wheel` in case a wheel is provided. In case you need to provide your own `buildPhase` and `installPhase` you can use `other`.
+* `catchConflicts` If `true`, abort package build if a package name appears more than once in dependency tree. Default is `true`.
+* `checkInputs` Dependencies needed for running the `checkPhase`. These are added to `buildInputs` when `doCheck = true`.
+
+#### `buildPythonApplication` function
+
+The `buildPythonApplication` function is practically the same as `buildPythonPackage`.
+The difference is that `buildPythonPackage` by default prefixes the names of the packages with the version of the interpreter.
+Because with an application we're not interested in multiple version the prefix is dropped.
+
+#### python.buildEnv function
+
+Python environments can be created using the low-level `pkgs.buildEnv` function.
+This example shows how to create an environment that has the Pyramid Web Framework.
+Saving the following as `default.nix`
+
+    with import <nixpkgs> {};
+
+    python.buildEnv.override {
+      extraLibs = [ pkgs.pythonPackages.pyramid ];
+      ignoreCollisions = true;
+    }
+
+and running `nix-build` will create
+
+    /nix/store/cf1xhjwzmdki7fasgr4kz6di72ykicl5-python-2.7.8-env
+
+with wrapped binaries in `bin/`.
+
+You can also use the `env` attribute to create local environments with needed
+packages installed. This is somewhat comparable to `virtualenv`. For example,
+running `nix-shell` with the following `shell.nix`
+
+    with import <nixpkgs> {};
+
+    (python3.buildEnv.override {
+      extraLibs = with python3Packages; [ numpy requests2 ];
+    }).env
+
+will drop you into a shell where Python will have the
+specified packages in its path.
+
+
+##### `python.buildEnv` arguments
+
+* `extraLibs`: List of packages installed inside the environment.
+* `postBuild`: Shell command executed after the build of environment.
+* `ignoreCollisions`: Ignore file collisions inside the environment (default is `false`).
+
+#### python.withPackages function
+
+The `python.withPackages` function provides a simpler interface to the `python.buildEnv` functionality.
+It takes a function as an argument that is passed the set of python packages and returns the list 
+of the packages to be included in the environment. Using the `withPackages` function, the previous
+example for the Pyramid Web Framework environment can be written like this:
+
+    with import <nixpkgs> {};
+
+    python.withPackages (ps: [ps.pyramid])
+
+`withPackages` passes the correct package set for the specific interpreter version as an 
+argument to the function. In the above example, `ps` equals `pythonPackages`.
+But you can also easily switch to using python3:
+    
+    with import <nixpkgs> {};
+
+    python3.withPackages (ps: [ps.pyramid])
+
+Now, `ps` is set to `python3Packages`, matching the version of the interpreter.
+
+As `python.withPackages` simply uses `python.buildEnv` under the hood, it also supports the `env`
+attribute. The `shell.nix` file from the previous section can thus be also written like this:
+
+    with import <nixpkgs> {};
+
+    (python33.withPackages (ps: [ps.numpy ps.requests2])).env
+
+In contrast to `python.buildEnv`, `python.withPackages` does not support the more advanced options
+such as `ignoreCollisions = true` or `postBuild`. If you need them, you have to use `python.buildEnv`.
+
+### Development mode
+
+Development or editable mode is supported. To develop Python packages
+`buildPythonPackage` has additional logic inside `shellPhase` to run `pip
+install -e . --prefix $TMPDIR/`for the package.
+
+Warning: `shellPhase` is executed only if `setup.py` exists.
+
+Given a `default.nix`:
+
+    with import <nixpkgs> {};
+
+    buildPythonPackage { name = "myproject";
+
+    buildInputs = with pkgs.pythonPackages; [ pyramid ];
+
+    src = ./.; }
+
+Running `nix-shell` with no arguments should give you
+the environment in which the package would be built with
+`nix-build`.
+
+Shortcut to setup environments with C headers/libraries and python packages:
+
+    $ nix-shell -p pythonPackages.pyramid zlib libjpeg git
+
+Note: There is a boolean value `lib.inNixShell` set to `true` if nix-shell is invoked.
+
+### Tools
+
+Packages inside nixpkgs are written by hand. However many tools exist in
+community to help save time. No tool is preferred at the moment.
+
+- [python2nix](https://github.com/proger/python2nix) by Vladimir Kirillov
+- [pypi2nix](https://github.com/garbas/pypi2nix) by Rok Garbas
+- [pypi2nix](https://github.com/offlinehacker/pypi2nix) by Jaka Hudoklin
+
+## FAQ
+
+### How can I install a working Python environment?
+
+As explained in the user's guide installing individual Python packages
+imperatively with `nix-env -i` or declaratively in `environment.systemPackages`
+is not supported. However, it is possible to install a Python environment with packages (`python.buildEnv`).
+
+In the following examples we create an environment with Python 3.5, `numpy` and `ipython`.
+As you might imagine there is one limitation here, and that's you can install
+only one environment at a time. You will notice the complaints about collisions
+when you try to install a second environment.
+
+#### Environment defined in separate `.nix` file
+
+Create a file, e.g. `build.nix`, with the following expression
+```nix
+with import <nixpkgs> {};
+
+pkgs.python35.withPackages (ps: with ps; [ numpy ipython ])
+```
+and install it in your profile with
+```
+nix-env -if build.nix
+```
+Now you can use the Python interpreter, as well as the extra packages that you added to the environment.
+
+#### Environment defined in `~/.nixpkgs/config.nix`
+
+If you prefer to, you could also add the environment as a package override to the Nixpkgs set.
+```
+  packageOverrides = pkgs: with pkgs; {
+    myEnv = python35.withPackages (ps: with ps; [ numpy ipython ]);
+  };
+```
+and install it in your profile with
+```
+nix-env -iA nixpkgs.myEnv
+```
+We're installing using the attribute path and assume the channels is named `nixpkgs`.
+Note that I'm using the attribute path here.
+
+#### Environment defined in `/etc/nixos/configuration.nix`
+
+For the sake of completeness, here's another example how to install the environment system-wide.
+
+```nix
+environment.systemPackages = with pkgs; [
+  (python35.withPackages(ps: with ps; [ numpy ipython ]))
+];
+```
+
+### How to solve circular dependencies?
+
+Consider the packages `A` and `B` that depend on each other. When packaging `B`,
+a solution is to override package `A` not to depend on `B` as an input. The same
+should also be done when packaging `A`.
+
+### How to override a Python package?
+
+We can override the interpreter and pass `packageOverrides`.
+In the following example we rename the `pandas` package and build it.
+```nix
+with import <nixpkgs> {};
+
+let
+  python = let
+    packageOverrides = self: super: {
+      pandas = super.pandas.override {name="foo";};
+    };
+  in pkgs.python35.override {inherit packageOverrides;};
+
+in python.pkgs.pandas
+```
+Using `nix-build` on this expression will build the package `pandas`
+but with the new name `foo`.
+
+All packages in the package set will use the renamed package.
+A typical use case is to switch to another version of a certain package.
+For example, in the Nixpkgs repository we have multiple versions of `django` and `scipy`.
+In the following example we use a different version of `scipy` and create an environment that uses it.
+All packages in the Python package set will now use the updated `scipy` version.
+
+```nix
+with import <nixpkgs> {};
+
+(
+let
+  packageOverrides = self: super: {
+    scipy = super.scipy_0_17;
+  };
+in (pkgs.python35.override {inherit packageOverrides;}).withPackages (ps: [ps.blaze])
+).env
+```
+The requested package `blaze` depends on `pandas` which itself depends on `scipy`.
+
+If you want the whole of Nixpkgs to use your modifications, then you can use `overlays`
+as explained in this manual. In the following example we build a `inkscape` using a different version of `numpy`.
+```
+let
+  pkgs = import <nixpkgs> {};
+  newpkgs = import pkgs.path { overlays = [ (pkgsself: pkgssuper: {
+    python27 = let
+      packageOverrides = self: super: {
+        numpy = super.numpy_1_10;
+      };
+    in pkgssuper.python27.override {inherit packageOverrides;};
+  } ) ]; };
+in newpkgs.inkscape
+```
+
+### `python setup.py bdist_wheel` cannot create .whl
+
+Executing `python setup.py bdist_wheel` in a `nix-shell `fails with
+```
+ValueError: ZIP does not support timestamps before 1980
+```
+This is because files are included that depend on items in the Nix store which have a timestamp of, that is, it corresponds to January the 1st, 1970 at 00:00:00. And as the error informs you, ZIP does not support that.
+The command `bdist_wheel` takes into account `SOURCE_DATE_EPOCH`, and `nix-shell` sets this to 1. By setting it to a value corresponding to 1980 or later, or by unsetting it, it is possible to build wheels.
+
+Use 1980 as timestamp:
+```
+nix-shell --run "SOURCE_DATE_EPOCH=315532800 python3 setup.py bdist_wheel"
+```
+or the current time:
+```
+nix-shell --run "SOURCE_DATE_EPOCH=$(date +%s) python3 setup.py bdist_wheel"
+```
+or unset:
+```
+nix-shell --run "unset SOURCE_DATE_EPOCH; python3 setup.py bdist_wheel"
+```
+
+### `install_data` / `data_files` problems
+
+If you get the following error:
+
+    could not create '/nix/store/6l1bvljpy8gazlsw2aw9skwwp4pmvyxw-python-2.7.8/etc':
+    Permission denied
+
+This is a [known bug](https://github.com/pypa/setuptools/issues/130) in setuptools.
+Setuptools `install_data` does not respect `--prefix`. An example of such package using the feature is `pkgs/tools/X11/xpra/default.nix`.
+As workaround install it as an extra `preInstall` step:
+
+    ${python.interpreter} setup.py install_data --install-dir=$out --root=$out
+    sed -i '/ = data\_files/d' setup.py
+
+
+###  Rationale of non-existent global site-packages
+
+On most operating systems a global `site-packages` is maintained. This however
+becomes problematic if you want to run multiple Python versions or have multiple
+versions of certain libraries for your projects. Generally, you would solve such
+issues by creating virtual environments using `virtualenv`.
+
+On Nix each package has an isolated dependency tree which, in the case of
+Python, guarantees the right versions of the interpreter and libraries or
+packages are available. There is therefore no need to maintain a global `site-packages`.
+
+If you want to create a Python environment for development, then the recommended
+method is to use `nix-shell`, either with or without the `python.buildEnv`
+function.
+
+### How to consume python modules using pip in a virtualenv like I am used to on other Operating Systems ?
+
+This is an example of a `default.nix` for a `nix-shell`, which allows to consume a `virtualenv` environment,
+and install python modules through `pip` the traditional way.
+
+Create this `default.nix` file, together with a `requirements.txt` and simply execute `nix-shell`.
+
+```
+with import <nixpkgs> {};
+with pkgs.python27Packages;
+
+stdenv.mkDerivation { 
+  name = "impurePythonEnv";
+  buildInputs = [
+    # these packages are required for virtualenv and pip to work:
+    #
+    python27Full
+    python27Packages.virtualenv
+    python27Packages.pip
+    # the following packages are related to the dependencies of your python 
+    # project. 
+    # In this particular example the python modules listed in the 
+    # requirements.tx require the following packages to be installed locally 
+    # in order to compile any binary extensions they may require.
+    #
+    taglib
+    openssl
+    git
+    libxml2
+    libxslt
+    libzip
+    stdenv
+    zlib ];
+  src = null;
+  shellHook = ''
+  # set SOURCE_DATE_EPOCH so that we can use python wheels
+  SOURCE_DATE_EPOCH=$(date +%s)
+  virtualenv --no-setuptools venv 
+  export PATH=$PWD/venv/bin:$PATH
+  pip install -r requirements.txt
+  '';
+}
+```
+
+Note that the `pip install` is an imperative action. So every time `nix-shell`
+is executed it will attempt to download the python modules listed in 
+requirements.txt. However these will be cached locally within the `virtualenv`
+folder and not downloaded again.
+
+
+## Contributing
+
+### Contributing guidelines
+
+Following rules are desired to be respected:
+
+* Python libraries are supposed to be called from `python-packages.nix` and packaged with `buildPythonPackage`. The expression of a library should be in `pkgs/development/python-modules/<name>/default.nix`. Libraries in `pkgs/top-level/python-packages.nix` are sorted quasi-alphabetically to avoid merge conflicts.
+* Python applications live outside of `python-packages.nix` and are packaged with `buildPythonApplication`.
+* Make sure libraries build for all Python interpreters.
+* By default we enable tests. Make sure the tests are found and, in the case of libraries, are passing for all interpreters. If certain tests fail they can be disabled individually. Try to avoid disabling the tests altogether. In any case, when you disable tests, leave a comment explaining why.
+* Commit names of Python libraries should include `pythonPackages`, for example `pythonPackages.numpy: 1.11 -> 1.12`.
--- a/doc/languages-frameworks/python.section.md
+++ b/doc/languages-frameworks/python.section.md
--- a/doc/languages-frameworks/qt.xml
+++ b/doc/languages-frameworks/qt.xml
@@ -2,55 +2,31 @@
         xmlns:xlink="http://www.w3.org/1999/xlink"
         xml:id="sec-language-qt">

-<title>Qt</title>
+<title>Qt and KDE</title>

-<para>
-Qt is a comprehensive desktop and mobile application development toolkit for C++.
-Legacy support is available for Qt 3 and Qt 4, but all current development uses Qt 5.
-The Qt 5 packages in Nixpkgs are updated frequently to take advantage of new features,
-but older versions are typically retained until their support window ends.
-The most important consideration in packaging Qt-based software is ensuring that each package and all its dependencies use the same version of Qt 5;
-this consideration motivates most of the tools described below.
-</para>
+<para>Qt is a comprehensive desktop and mobile application development toolkit for C++. Legacy support is available for Qt 3 and Qt 4, but all current development uses Qt 5. The Qt 5 packages in Nixpkgs are updated frequently to take advantage of new features, but older versions are typically retained to support packages that may not be compatible with the latest version. When packaging applications and libraries for Nixpkgs, it is important to ensure that compatible versions of Qt 5 are used throughout; this consideration motivates the tools described below.</para>

-<section xml:id="ssec-qt-libraries"><title>Packaging Libraries for Nixpkgs</title>
+<section xml:id="ssec-qt-libraries"><title>Libraries</title>

-<para>
-Whenever possible, libraries that use Qt 5 should be built with each available version.
-Packages providing libraries should be added to the top-level function <varname>mkLibsForQt5</varname>,
-which is used to build a set of libraries for every Qt 5 version.
-A special <varname>callPackage</varname> function is used in this scope to ensure that the entire dependency tree uses the same Qt 5 version.
-Import dependencies unqualified, i.e., <literal>qtbase</literal> not <literal>qt5.qtbase</literal>.
-<emphasis>Do not</emphasis> import a package set such as <literal>qt5</literal> or <literal>libsForQt5</literal>.
-</para>
+<para>Libraries that depend on Qt 5 should be built with each available version to avoid linking a dependent package against incompatible versions of Qt 5. (Although Qt 5 maintains backward ABI compatibility, linking against multiple versions at once is generally not possible; at best it will lead to runtime faults.) Packages that provide libraries should be added to the top-level function <varname>mkLibsForQt5</varname>, which is used to build a set of libraries for every Qt 5 version. The <varname>callPackage</varname> provided in this scope will ensure that only one Qt version will be used throughout the dependency tree. Dependencies should be imported unqualified, i.e. <literal>qtbase</literal> not <literal>qt5.qtbase</literal>, so that <varname>callPackage</varname> can do its work. <emphasis>Do not</emphasis> import a package set such as <literal>qt5</literal> or <literal>libsForQt5</literal> into your package; although it may work fine in the moment, it could well break at the next Qt update.</para>

-<para>
-If a library does not support a particular version of Qt 5, it is best to mark it as broken by setting its <literal>meta.broken</literal> attribute.
-A package may be marked broken for certain versions by testing the <literal>qtbase.version</literal> attribute, which will always give the current Qt 5 version.
-</para>
+<para>If a library does not support a particular version of Qt 5, it is best to mark it as broken by setting its <literal>meta.broken</literal> attribute. A package may be marked broken for certain versions by testing the <literal>qtbase.version</literal> attribute, which will always give the current Qt 5 version.</para>

 </section>

-<section xml:id="ssec-qt-applications"><title>Packaging Applications for Nixpkgs</title>
+<section xml:id="ssec-qt-applications"><title>Applications</title>

-<para>
-Call your application expression using <literal>libsForQt5.callPackage</literal> instead of <literal>callPackage</literal>.
-Import dependencies unqualified, i.e., <literal>qtbase</literal> not <literal>qt5.qtbase</literal>.
-<emphasis>Do not</emphasis> import a package set such as <literal>qt5</literal> or <literal>libsForQt5</literal>.
-</para>
+<para>Applications generally do not need to be built with every Qt version because they do not provide any libraries for dependent packages to link against. The primary consideration is merely ensuring that the application itself and its dependencies are linked against only one version of Qt. To call your application expression, use <literal>libsForQt5.callPackage</literal> instead of <literal>callPackage</literal>. Dependencies should be imported unqualified, i.e. <literal>qtbase</literal> not <literal>qt5.qtbase</literal>. <emphasis>Do not</emphasis> import a package set such as <literal>qt5</literal> or <literal>libsForQt5</literal> into your package; although it may work fine in the moment, it could well break at the next Qt update.</para>

-<para>
-Qt 5 maintains strict backward compatibility, so it is generally best to build an application package against the latest version using the <varname>libsForQt5</varname> library set.
-In case a package does not build with the latest Qt version, it is possible to pick a set pinned to a particular version, e.g. <varname>libsForQt55</varname> for Qt 5.5, if that is the latest version the package supports.
-If a package must be pinned to an older Qt version, be sure to file a bug upstream;
-because Qt is strictly backwards-compatible, any incompatibility is by definition a bug in the application.
-</para>
+<para>It is generally best to build an application package against the <varname>libsForQt5</varname> library set. In case a package does not build with the latest Qt version, it is possible to pick a set pinned to a particular version, e.g. <varname>libsForQt55</varname> for Qt 5.5, if that is the latest version the package supports.</para>

-<para>
-When testing applications in Nixpkgs, it is a common practice to build the package with <literal>nix-build</literal> and run it using the created symbolic link.
-This will not work with Qt applications, however, because they have many hard runtime requirements that can only be guaranteed if the package is actually installed.
-To test a Qt application, install it with <literal>nix-env</literal> or run it inside <literal>nix-shell</literal>.
-</para>
+<para>Qt-based applications require that several paths be set at runtime. This is accomplished by wrapping the provided executables in a package with <literal>wrapQtProgram</literal> or <literal>makeQtWrapper</literal> during the <literal>postFixup</literal> phase. To use the wrapper generators, add <literal>makeQtWrapper</literal> to <literal>nativeBuildInputs</literal>. The wrapper generators support the same options as <literal>wrapProgram</literal> and <literal>makeWrapper</literal> respectively. It is usually only necessary to generate wrappers for programs intended to be invoked by the user.</para>
+
+</section>
+
+<section xml:id="ssec-qt-kde"><title>KDE</title>
+
+<para>The KDE Frameworks are a set of libraries for Qt 5 which form the basis of the Plasma desktop environment and the KDE Applications suite. Packaging a Frameworks-based library does not require any steps beyond those described above for general Qt-based libraries. Frameworks-based applications should not use <literal>makeQtWrapper</literal>; instead, use <literal>kdeWrapper</literal> to create the necessary wrappers: <literal>kdeWrapper { unwrapped = <replaceable>expr</replaceable>; targets = <replaceable>exes</replaceable>; }</literal>, where <replaceable>expr</replaceable> is the un-wrapped package expression and <replaceable>exes</replaceable> is a list of strings giving the relative paths to programs in the package which should be wrapped.</para>

 </section>

--- a/doc/languages-frameworks/r.section.md
+++ b/doc/languages-frameworks/r.section.md
@@ -1,120 +0,0 @@
-R packages
-==========
-
-## Installation
-
-Define an environment for R that contains all the libraries that you'd like to
-use by adding the following snippet to your $HOME/.config/nixpkgs/config.nix file:
-
-```nix
-{
-    packageOverrides = super: let self = super.pkgs; in
-    {
-
-        rEnv = super.rWrapper.override {
-            packages = with self.rPackages; [
-                devtools
-                ggplot2
-                reshape2
-                yaml
-                optparse
-                ];
-        };
-    };
-}
-```
-
-Then you can use `nix-env -f "<nixpkgs>" -iA rEnv` to install it into your user
-profile. The set of available libraries can be discovered by running the
-command `nix-env -f "<nixpkgs>" -qaP -A rPackages`. The first column from that
-output is the name that has to be passed to rWrapper in the code snipped above.
-
-However, if you'd like to add a file to your project source to make the
-environment available for other contributors, you can create a `default.nix`
-file like so:
-```nix
-let
-  pkgs = import <nixpkgs> {};
-  stdenv = pkgs.stdenv;
-in with pkgs; {
-  myProject = stdenv.mkDerivation {
-    name = "myProject";
-    version = "1";
-    src = if pkgs.lib.inNixShell then null else nix;
-
-    buildInputs = with rPackages; [
-      R
-      ggplot2
-      knitr
-    ];
-  };
-}
-```
-and then run `nix-shell .` to be dropped into a shell with those packages
-available.
-
-## RStudio
-
-RStudio uses a standard set of packages and ignores any custom R
-environments or installed packages you may have.  To create a custom
-environment, see `rstudioWrapper`, which functions similarly to
-`rWrapper`:
-
-```nix
-{
-    packageOverrides = super: let self = super.pkgs; in
-    {
-
-        rstudioEnv = super.rstudioWrapper.override {
-            packages = with self.rPackages; [
-                dplyr
-                ggplot2
-                reshape2
-                ];
-        };
-    };
-}
-```
-
-Then like above, `nix-env -f "<nixpkgs>" -iA rstudioEnv` will install
-this into your user profile.
-
-Alternatively, you can create a self-contained `shell.nix` without the need to
-modify any configuration files:
-
-```nix
-{ pkgs ? import <nixpkgs> {}
-}:
-
-pkgs.rstudioWrapper.override {
-  packages = with pkgs.rPackages; [ dplyr ggplot2 reshape2 ];
-}
-
-```
-
-Executing `nix-shell` will then drop you into an environment equivalent to the
-one above. If you need additional packages just add them to the list and
-re-enter the shell.
-
-## Updating the package set
-
-```bash
-nix-shell generate-shell.nix
-
-Rscript generate-r-packages.R cran  > cran-packages.nix.new
-mv cran-packages.nix.new cran-packages.nix
-
-Rscript generate-r-packages.R bioc  > bioc-packages.nix.new
-mv bioc-packages.nix.new bioc-packages.nix
-```
-
-`generate-r-packages.R <repo>` reads  `<repo>-packages.nix`, therefor the renaming.
-
-
-## Testing if the Nix-expression could be evaluated
-
-```bash
-nix-build test-evaluation.nix --dry-run
-```
-
-If this exits fine, the expression is ok. If not, you have to edit `default.nix`
--- a/doc/languages-frameworks/ruby.xml
+++ b/doc/languages-frameworks/ruby.xml
@@ -4,14 +4,10 @@

 <title>Ruby</title>

-<para>There currently is support to bundle applications that are packaged as
-Ruby gems. The utility "bundix" allows you to write a
-<filename>Gemfile</filename>, let bundler create a
-<filename>Gemfile.lock</filename>, and then convert this into a nix
-expression that contains all Gem dependencies automatically.
-</para>
+  <para>There currently is support to bundle applications that are packaged as Ruby gems. The utility "bundix" allows you to write a <filename>Gemfile</filename>, let bundler create a <filename>Gemfile.lock</filename>, and then convert
+  this into a nix expression that contains all Gem dependencies automatically.</para>

-<para>For example, to package sensu, we did:</para>
+  <para>For example, to package sensu, we did:</para>

 <screen>
 <![CDATA[$ cd pkgs/servers/monitoring
@@ -20,7 +16,8 @@ $ cd sensu
 $ cat > Gemfile
 source 'https://rubygems.org'
 gem 'sensu'
-$ $(nix-build '<nixpkgs>' -A bundix --no-out-link)/bin/bundix --magic
+$ nix-shell -p bundler --command "bundler package --path /tmp/vendor/bundle"
+$ $(nix-build '<nixpkgs>' -A bundix)/bin/bundix
 $ cat > default.nix
 { lib, bundlerEnv, ruby }:

@@ -42,61 +39,15 @@ bundlerEnv rec {
 }]]>
 </screen>

-<para>Please check in the <filename>Gemfile</filename>,
-<filename>Gemfile.lock</filename> and the
-<filename>gemset.nix</filename> so future updates can be run easily.
+<para>Please check in the <filename>Gemfile</filename>, <filename>Gemfile.lock</filename> and the <filename>gemset.nix</filename> so future updates can be run easily.
 </para>

-<para>For tools written in Ruby - i.e. where the desire is to install
-a package and then execute e.g. <command>rake</command> at the command
-line, there is an alternative builder called <literal>bundlerApp</literal>.
-Set up the <filename>gemset.nix</filename> the same way, and then, for
-example:
-</para>
-
-<screen>
-<![CDATA[{ lib, bundlerApp }:
-
-bundlerApp {
-  pname = "corundum";
-  gemdir = ./.;
-  exes = [ "corundum-skel" ];
-
-  meta = with lib; {
-    description = "Tool and libraries for maintaining Ruby gems.";
-    homepage    = https://github.com/nyarly/corundum;
-    license     = licenses.mit;
-    maintainers = [ maintainers.nyarly ];
-    platforms   = platforms.unix;
-  };
-}]]>
-</screen>
-
-<para>The chief advantage of <literal>bundlerApp</literal> over
-<literal>bundlerEnv</literal> is the executables introduced in the
-environment are precisely those selected in the <literal>exes</literal>
-list, as opposed to <literal>bundlerEnv</literal> which adds all the
-executables made available by gems in the gemset, which can mean e.g.
-<command>rspec</command> or <command>rake</command> in unpredictable
-versions available from various packages.
-</para>
-
-<para>Resulting derivations for both builders also have two helpful
-attributes, <literal>env</literal> and <literal>wrappedRuby</literal>.
-The first one allows one to quickly drop into
-<command>nix-shell</command> with the specified environment present.
-E.g. <command>nix-shell -A sensu.env</command> would give you an
-environment with Ruby preset so it has all the libraries necessary
-for <literal>sensu</literal> in its paths. The second one can be
-used to make derivations from custom Ruby scripts which have
-<filename>Gemfile</filename>s with their dependencies specified. It is
-a derivation with <command>ruby</command> wrapped so it can find all
-the needed dependencies. For example, to make a derivation
-<literal>my-script</literal> for a <filename>my-script.rb</filename>
-(which should be placed in <filename>bin</filename>) you should run
-<command>bundix</command> as specified above and then use
-<literal>bundlerEnv</literal> like this:
-</para>
+<para>Resulting derivations also have two helpful items, <literal>env</literal> and <literal>wrapper</literal>. The first one allows one to quickly drop into
+<command>nix-shell</command> with the specified environment present. E.g. <command>nix-shell -A sensu.env</command> would give you an environment with Ruby preset
+so it has all the libraries necessary for <literal>sensu</literal> in its paths. The second one can be used to make derivations from custom Ruby scripts which have
+<filename>Gemfile</filename>s with their dependencies specified. It is a derivation with <command>ruby</command> wrapped so it can find all the needed dependencies.
+For example, to make a derivation <literal>my-script</literal> for a <filename>my-script.rb</filename> (which should be placed in <filename>bin</filename>) you should
+run <command>bundix</command> as specified above and then use <literal>bundlerEnv</literal> lile this:</para>

 <programlisting>
 <![CDATA[let env = bundlerEnv {
@@ -110,9 +61,13 @@ the needed dependencies. For example, to make a derivation

 in stdenv.mkDerivation {
  name = "my-script";
-  buildInputs = [ env.wrappedRuby ];
+
+  buildInputs = [ env.wrapper ];
+
  script = ./my-script.rb;
+
  buildCommand = ''
+    mkdir -p $out/bin
    install -D -m755 $script $out/bin/my-script
    patchShebangs $out/bin/my-script
  '';
@@ -120,3 +75,4 @@ in stdenv.mkDerivation {
 </programlisting>

 </section>
+
--- a/doc/languages-frameworks/rust.section.md
+++ b/doc/languages-frameworks/rust.section.md
@@ -1,393 +0,0 @@
---
-title: Rust
-author: Matthias Beyer
-date: 2017-03-05
---
-
-# User's Guide to the Rust Infrastructure
-
-To install the rust compiler and cargo put
-
-```
-rustc
-cargo
-```
-
-into the `environment.systemPackages` or bring them into
-scope with `nix-shell -p rustc cargo`.
-
-> If you are using NixOS and you want to use rust without a nix expression you
-> probably want to add the following in your `configuration.nix` to build
-> crates with C dependencies.
->
->     environment.systemPackages = [binutils gcc gnumake openssl pkgconfig]
-
-For daily builds (beta and nightly) use either rustup from
-nixpkgs or use the [Rust nightlies
-overlay](#using-the-rust-nightlies-overlay).
-
-## Compiling Rust applications with Cargo
-
-Rust applications are packaged by using the `buildRustPackage` helper from `rustPlatform`:
-
-```
-rustPlatform.buildRustPackage rec {
-  name = "ripgrep-${version}";
-  version = "0.4.0";
-
-  src = fetchFromGitHub {
-    owner = "BurntSushi";
-    repo = "ripgrep";
-    rev = "${version}";
-    sha256 = "0y5d1n6hkw85jb3rblcxqas2fp82h3nghssa4xqrhqnz25l799pj";
-  };
-
-  cargoSha256 = "0q68qyl2h6i0qsz82z840myxlnjay8p1w5z7hfyr8fqp7wgwa9cx";
-
-  meta = with stdenv.lib; {
-    description = "A fast line-oriented regex search tool, similar to ag and ack";
-    homepage = https://github.com/BurntSushi/ripgrep;
-    license = licenses.unlicense;
-    maintainers = [ maintainers.tailhook ];
-    platforms = platforms.all;
-  };
-}
-```
-
-`buildRustPackage` requires a `cargoSha256` attribute which is computed over
-all crate sources of this package. Currently it is obtained by inserting a
-fake checksum into the expression and building the package once. The correct
-checksum can be then take from the failed build.
-
-To install crates with nix there is also an experimental project called
-[nixcrates](https://github.com/fractalide/nixcrates).
-
-## Compiling Rust crates using Nix instead of Cargo
-
-### Simple operation
-
-When run, `cargo build` produces a file called `Cargo.lock`,
-containing pinned versions of all dependencies. Nixpkgs contains a
-tool called `carnix` (`nix-env -iA nixos.carnix`), which can be used
-to turn a `Cargo.lock` into a Nix expression.
-
-That Nix expression calls `rustc` directly (hence bypassing Cargo),
-and can be used to compile a crate and all its dependencies. Here is
-an example for a minimal `hello` crate:
-
-
-    $ cargo new hello
-    $ cd hello
-    $ cargo build
-     Compiling hello v0.1.0 (file:///tmp/hello)
-      Finished dev [unoptimized + debuginfo] target(s) in 0.20 secs
-    $ carnix -o hello.nix --src ./. Cargo.lock --standalone
-    $ nix-build hello.nix -A hello_0_1_0
-
-Now, the file produced by the call to `carnix`, called `hello.nix`, looks like:
-
-```
-# Generated by carnix 0.6.5: carnix -o hello.nix --src ./. Cargo.lock --standalone
-{ lib, buildPlatform, buildRustCrate, fetchgit }:
-let kernel = buildPlatform.parsed.kernel.name;
-    # ... (content skipped)
-in
-rec {
-  hello = f: hello_0_1_0 { features = hello_0_1_0_features { hello_0_1_0 = f; }; };
-  hello_0_1_0_ = { dependencies?[], buildDependencies?[], features?[] }: buildRustCrate {
-    crateName = "hello";
-    version = "0.1.0";
-    authors = [ "pe@pijul.org <pe@pijul.org>" ];
-    src = ./.;
-    inherit dependencies buildDependencies features;
-  };
-  hello_0_1_0 = { features?(hello_0_1_0_features {}) }: hello_0_1_0_ {};
-  hello_0_1_0_features = f: updateFeatures f (rec {
-        hello_0_1_0.default = (f.hello_0_1_0.default or true);
-    }) [ ];
-}
-```
-
-In particular, note that the argument given as `--src` is copied
-verbatim to the source. If we look at a more complicated
-dependencies, for instance by adding a single line `libc="*"` to our
-`Cargo.toml`, we first need to run `cargo build` to update the
-`Cargo.lock`. Then, `carnix` needs to be run again, and produces the
-following nix file:
-
-```
-# Generated by carnix 0.6.5: carnix -o hello.nix --src ./. Cargo.lock --standalone
-{ lib, buildPlatform, buildRustCrate, fetchgit }:
-let kernel = buildPlatform.parsed.kernel.name;
-    # ... (content skipped)
-in
-rec {
-  hello = f: hello_0_1_0 { features = hello_0_1_0_features { hello_0_1_0 = f; }; };
-  hello_0_1_0_ = { dependencies?[], buildDependencies?[], features?[] }: buildRustCrate {
-    crateName = "hello";
-    version = "0.1.0";
-    authors = [ "pe@pijul.org <pe@pijul.org>" ];
-    src = ./.;
-    inherit dependencies buildDependencies features;
-  };
-  libc_0_2_36_ = { dependencies?[], buildDependencies?[], features?[] }: buildRustCrate {
-    crateName = "libc";
-    version = "0.2.36";
-    authors = [ "The Rust Project Developers" ];
-    sha256 = "01633h4yfqm0s302fm0dlba469bx8y6cs4nqc8bqrmjqxfxn515l";
-    inherit dependencies buildDependencies features;
-  };
-  hello_0_1_0 = { features?(hello_0_1_0_features {}) }: hello_0_1_0_ {
-    dependencies = mapFeatures features ([ libc_0_2_36 ]);
-  };
-  hello_0_1_0_features = f: updateFeatures f (rec {
-    hello_0_1_0.default = (f.hello_0_1_0.default or true);
-    libc_0_2_36.default = true;
-  }) [ libc_0_2_36_features ];
-  libc_0_2_36 = { features?(libc_0_2_36_features {}) }: libc_0_2_36_ {
-    features = mkFeatures (features.libc_0_2_36 or {});
-  };
-  libc_0_2_36_features = f: updateFeatures f (rec {
-    libc_0_2_36.default = (f.libc_0_2_36.default or true);
-    libc_0_2_36.use_std =
-      (f.libc_0_2_36.use_std or false) ||
-      (f.libc_0_2_36.default or false) ||
-      (libc_0_2_36.default or false);
-  }) [];
-}
-```
-
-Here, the `libc` crate has no `src` attribute, so `buildRustCrate`
-will fetch it from [crates.io](https://crates.io). A `sha256`
-attribute is still needed for Nix purity.
-
-### Handling external dependencies
-
-Some crates require external libraries. For crates from
-[crates.io](https://crates.io), such libraries can be specified in
-`defaultCrateOverrides` package in nixpkgs itself.
-
-Starting from that file, one can add more overrides, to add features
-or build inputs by overriding the hello crate in a seperate file.
-
-```
-with import <nixpkgs> {};
-((import ./hello.nix).hello {}).override {
-  crateOverrides = defaultCrateOverrides // {
-    hello = attrs: { buildInputs = [ openssl ]; };
-  };
-}
-```
-
-Here, `crateOverrides` is expected to be a attribute set, where the
-key is the crate name without version number and the value a function.
-The function gets all attributes passed to `buildRustCrate` as first
-argument and returns a set that contains all attribute that should be
-overwritten.
-
-For more complicated cases, such as when parts of the crate's
-derivation depend on the the crate's version, the `attrs` argument of
-the override above can be read, as in the following example, which
-patches the derivation:
-
-```
-with import <nixpkgs> {};
-((import ./hello.nix).hello {}).override {
-  crateOverrides = defaultCrateOverrides // {
-    hello = attrs: lib.optionalAttrs (lib.versionAtLeast attrs.version "1.0")  {
-      postPatch = ''
-        substituteInPlace lib/zoneinfo.rs \
-          --replace "/usr/share/zoneinfo" "${tzdata}/share/zoneinfo"
-      '';
-    };
-  };
-}
-```
-
-Another situation is when we want to override a nested
-dependency. This actually works in the exact same way, since the
-`crateOverrides` parameter is forwarded to the crate's
-dependencies. For instance, to override the build inputs for crate
-`libc` in the example above, where `libc` is a dependency of the main
-crate, we could do:
-
-```
-with import <nixpkgs> {};
-((import hello.nix).hello {}).override {
-  crateOverrides = defaultCrateOverrides // {
-    libc = attrs: { buildInputs = []; };
-  };
-}
-```
-
-### Options and phases configuration
-
-Actually, the overrides introduced in the previous section are more
-general. A number of other parameters can be overridden:
-
- The version of rustc used to compile the crate:
-
-  ```
-  (hello {}).override { rust = pkgs.rust; };
-  ```
-
- Whether to build in release mode or debug mode (release mode by
-  default):
-
-  ```
-  (hello {}).override { release = false; };
-  ```
-
- Whether to print the commands sent to rustc when building
-  (equivalent to `--verbose` in cargo:
-
-  ```
-  (hello {}).override { verbose = false; };
-  ```
-
- Extra arguments to be passed to `rustc`:
-
-  ```
-  (hello {}).override { extraRustcOpts = "-Z debuginfo=2"; };
-  ```
-
- Phases, just like in any other derivation, can be specified using
-  the following attributes: `preUnpack`, `postUnpack`, `prePatch`,
-  `patches`, `postPatch`, `preConfigure` (in the case of a Rust crate,
-  this is run before calling the "build" script), `postConfigure`
-  (after the "build" script),`preBuild`, `postBuild`, `preInstall` and
-  `postInstall`. As an example, here is how to create a new module
-  before running the build script:
-
-  ```
-  (hello {}).override {
-    preConfigure = ''
-       echo "pub const PATH=\"${hi.out}\";" >> src/path.rs"
-    '';
-  };
-  ```
-
-### Features
-
-One can also supply features switches. For example, if we want to
-compile `diesel_cli` only with the `postgres` feature, and no default
-features, we would write:
-
-```
-(callPackage ./diesel.nix {}).diesel {
-  default = false;
-  postgres = true;
-}
-```
-
-Where `diesel.nix` is the file generated by Carnix, as explained above.
-
-
-## Setting Up `nix-shell`
-Oftentimes you want to develop code from within `nix-shell`. Unfortunately
-`buildRustCrate` does not support common `nix-shell` operations directly
-(see [this issue](https://github.com/NixOS/nixpkgs/issues/37945))
-so we will use `stdenv.mkDerivation` instead.
-
-Using the example `hello` project above, we want to do the following:
- Have access to `cargo` and `rustc`
- Have the `openssl` library available to a crate through it's _normal_
-  compilation mechanism (`pkg-config`).
-
-A typical `shell.nix` might look like:
-
-```
-with import <nixpkgs> {};
-
-stdenv.mkDerivation {
-  name = "rust-env";
-  buildInputs = [
-    rustc cargo
-
-    # Example Additional Dependencies
-    pkgconfig openssl
-  ];
-
-  # Set Environment Variables
-  RUST_BACKTRACE = 1;
-}
-```
-
-You should now be able to run the following:
-```
-$ nix-shell --pure
-$ cargo build
-$ cargo test
-```
-
-### Controlling Rust Version Inside `nix-shell`
-To control your rust version (i.e. use nightly) from within `shell.nix` (or
-other nix expressions) you can use the following `shell.nix`
-
-```
-# Latest Nightly
-with import <nixpkgs> {};
-let src = fetchFromGitHub {
-      owner = "mozilla";
-      repo = "nixpkgs-mozilla";
-      # commit from: 2018-03-27
-      rev = "2945b0b6b2fd19e7d23bac695afd65e320efcebe";
-      sha256 = "034m1dryrzh2lmjvk3c0krgip652dql46w5yfwpvh7gavd3iypyw";
-   };
-in
-with import "${src.out}/rust-overlay.nix" pkgs pkgs;
-stdenv.mkDerivation {
-  name = "rust-env";
-  buildInputs = [
-    # Note: to use use stable, just replace `nightly` with `stable`
-    latest.rustChannels.nightly.rust
-
-    # Add some extra dependencies from `pkgs`
-    pkgconfig openssl
-  ];
-
-  # Set Environment Variables
-  RUST_BACKTRACE = 1;
-}
-```
-
-Now run:
-```
-$ rustc --version
-rustc 1.26.0-nightly (188e693b3 2018-03-26)
-```
-
-To see that you are using nightly.
-
-
-## Using the Rust nightlies overlay
-
-Mozilla provides an overlay for nixpkgs to bring a nightly version of Rust into scope.
-This overlay can _also_ be used to install recent unstable or stable versions
-of Rust, if desired.
-
-To use this overlay, clone
-[nixpkgs-mozilla](https://github.com/mozilla/nixpkgs-mozilla),
-and create a symbolic link to the file
-[rust-overlay.nix](https://github.com/mozilla/nixpkgs-mozilla/blob/master/rust-overlay.nix)
-in the `~/.config/nixpkgs/overlays` directory.
-
-    $ git clone https://github.com/mozilla/nixpkgs-mozilla.git
-    $ mkdir -p ~/.config/nixpkgs/overlays
-    $ ln -s $(pwd)/nixpkgs-mozilla/rust-overlay.nix ~/.config/nixpkgs/overlays/rust-overlay.nix
-
-The latest version can be installed with the following command:
-
-    $ nix-env -Ai nixos.latest.rustChannels.stable.rust
-
-Or using the attribute with nix-shell:
-
-    $ nix-shell -p nixos.latest.rustChannels.stable.rust
-
-To install the beta or nightly channel, "stable" should be substituted by
-"nightly" or "beta", or
-use the function provided by this overlay to pull a version based on a
-build date.
-
-The overlay automatically updates itself as it uses the same source as
-[rustup](https://www.rustup.rs/).
--- a/doc/languages-frameworks/vim.md
+++ b/doc/languages-frameworks/vim.md
@@ -0,0 +1,102 @@
+---
+title: User's Guide for Vim in Nixpkgs
+author: Marc Weber
+date: 2016-06-25
+---
+# User's Guide to Vim Plugins/Addons/Bundles/Scripts in Nixpkgs
+
+You'll get a vim(-your-suffix) in PATH also loading the plugins you want.
+Loading can be deferred; see examples.
+
+VAM (=vim-addon-manager) and Pathogen plugin managers are supported.
+Vundle, NeoBundle could be your turn.
+
+## dependencies by Vim plugins
+
+VAM introduced .json files supporting dependencies without versioning
+assuming that "using latest version" is ok most of the time.
+
+## HOWTO
+
+First create a vim-scripts file having one plugin name per line. Example:
+
+    "tlib"
+    {'name': 'vim-addon-sql'}
+    {'filetype_regex': '\%(vim)$', 'names': ['reload', 'vim-dev-plugin']}
+
+Such vim-scripts file can be read by VAM as well like this:
+
+    call vam#Scripts(expand('~/.vim-scripts'), {})
+
+Create a default.nix file:
+
+    { nixpkgs ? import <nixpkgs> {}, compiler ? "ghc7102" }:
+    nixpkgs.vim_configurable.customize { name = "vim"; vimrcConfig.vam.pluginDictionaries = [ "vim-addon-vim2nix" ]; }
+
+Create a generate.vim file:
+
+    ActivateAddons vim-addon-vim2nix
+    let vim_scripts = "vim-scripts"
+    call nix#ExportPluginsForNix({
+    \  'path_to_nixpkgs': eval('{"'.substitute(substitute(substitute($NIX_PATH, ':', ',', 'g'), '=',':', 'g'), '\([:,]\)', '"\1"',"g").'"}')["nixpkgs"],
+    \  'cache_file': '/tmp/vim2nix-cache',
+    \  'try_catch': 0,
+    \  'plugin_dictionaries': ["vim-addon-manager"]+map(readfile(vim_scripts), 'eval(v:val)')
+    \ })
+
+Then run
+
+    nix-shell -p vimUtils.vim_with_vim2nix --command "vim -c 'source generate.vim'"
+
+You should get a Vim buffer with the nix derivations (output1) and vam.pluginDictionaries (output2).
+You can add your vim to your system's configuration file like this and start it by "vim-my":
+
+    my-vim =
+     let plugins = let inherit (vimUtils) buildVimPluginFrom2Nix; in {
+          copy paste output1 here
+     }; in vim_configurable.customize {
+       name = "vim-my";
+
+       vimrcConfig.vam.knownPlugins = plugins; # optional
+       vimrcConfig.vam.pluginDictionaries = [
+          copy paste output2 here
+       ];
+
+       # Pathogen would be
+       # vimrcConfig.pathogen.knownPlugins = plugins; # plugins
+       # vimrcConfig.pathogen.pluginNames = ["tlib"];
+     };
+
+
+Sample output1:
+
+    "reload" = buildVimPluginFrom2Nix { # created by nix#NixDerivation
+      name = "reload";
+      src = fetchgit {
+        url = "git://github.com/xolox/vim-reload";
+        rev = "0a601a668727f5b675cb1ddc19f6861f3f7ab9e1";
+        sha256 = "0vb832l9yxj919f5hfg6qj6bn9ni57gnjd3bj7zpq7d4iv2s4wdh";
+      };
+      dependencies = ["nim-misc"];
+
+    };
+    [...]
+
+Sample output2:
+
+    [
+      ''vim-addon-manager''
+      ''tlib''
+      { "name" = ''vim-addon-sql''; }
+      { "filetype_regex" = ''\%(vim)$$''; "names" = [ ''reload'' ''vim-dev-plugin'' ]; }
+    ]
+
+
+## Important repositories
+
+- [vim-pi](https://bitbucket.org/vimcommunity/vim-pi) is a plugin repository
+  from VAM plugin manager meant to be used by others as well used by
+
+- [vim2nix](http://github.com/MarcWeber/vim-addon-vim2nix) which generates the
+  .nix code
+
--- a/doc/languages-frameworks/vim.section.md
+++ b/doc/languages-frameworks/vim.section.md
@@ -1,135 +0,0 @@
---
-title: User's Guide for Vim in Nixpkgs
-author: Marc Weber
-date: 2016-06-25
---
-# User's Guide to Vim Plugins/Addons/Bundles/Scripts in Nixpkgs
-
-You'll get a vim(-your-suffix) in PATH also loading the plugins you want.
-Loading can be deferred; see examples.
-
-Vim packages, VAM (=vim-addon-manager) and Pathogen are supported to load
-packages.
-
-## Custom configuration
-
-Adding custom .vimrc lines can be done using the following code:
-
-```
-vim_configurable.customize {
-  name = "vim-with-plugins";
-
-  vimrcConfig.customRC = ''
-    set hidden
-  '';
-}
-```
-
-## Vim packages
-
-To store you plugins in Vim packages the following example can be used:
-
-```
-vim_configurable.customize {
-  vimrcConfig.packages.myVimPackage = with pkgs.vimPlugins; {
-    # loaded on launch
-    start = [ youcompleteme fugitive ];
-    # manually loadable by calling `:packadd $plugin-name`
-    opt = [ phpCompletion elm-vim ];
-    # To automatically load a plugin when opening a filetype, add vimrc lines like:
-    # autocmd FileType php :packadd phpCompletion
-  }
-};
-```
-
-## VAM
-
-### dependencies by Vim plugins
-
-VAM introduced .json files supporting dependencies without versioning
-assuming that "using latest version" is ok most of the time.
-
-### Example
-
-First create a vim-scripts file having one plugin name per line. Example:
-
-    "tlib"
-    {'name': 'vim-addon-sql'}
-    {'filetype_regex': '\%(vim)$', 'names': ['reload', 'vim-dev-plugin']}
-
-Such vim-scripts file can be read by VAM as well like this:
-
-    call vam#Scripts(expand('~/.vim-scripts'), {})
-
-Create a default.nix file:
-
-    { nixpkgs ? import <nixpkgs> {}, compiler ? "ghc7102" }:
-    nixpkgs.vim_configurable.customize { name = "vim"; vimrcConfig.vam.pluginDictionaries = [ "vim-addon-vim2nix" ]; }
-
-Create a generate.vim file:
-
-    ActivateAddons vim-addon-vim2nix
-    let vim_scripts = "vim-scripts"
-    call nix#ExportPluginsForNix({
-    \  'path_to_nixpkgs': eval('{"'.substitute(substitute(substitute($NIX_PATH, ':', ',', 'g'), '=',':', 'g'), '\([:,]\)', '"\1"',"g").'"}')["nixpkgs"],
-    \  'cache_file': '/tmp/vim2nix-cache',
-    \  'try_catch': 0,
-    \  'plugin_dictionaries': ["vim-addon-manager"]+map(readfile(vim_scripts), 'eval(v:val)')
-    \ })
-
-Then run
-
-    nix-shell -p vimUtils.vim_with_vim2nix --command "vim -c 'source generate.vim'"
-
-You should get a Vim buffer with the nix derivations (output1) and vam.pluginDictionaries (output2).
-You can add your vim to your system's configuration file like this and start it by "vim-my":
-
-    my-vim =
-     let plugins = let inherit (vimUtils) buildVimPluginFrom2Nix; in {
-          copy paste output1 here
-     }; in vim_configurable.customize {
-       name = "vim-my";
-
-       vimrcConfig.vam.knownPlugins = plugins; # optional
-       vimrcConfig.vam.pluginDictionaries = [
-          copy paste output2 here
-       ];
-
-       # Pathogen would be
-       # vimrcConfig.pathogen.knownPlugins = plugins; # plugins
-       # vimrcConfig.pathogen.pluginNames = ["tlib"];
-     };
-
-
-Sample output1:
-
-    "reload" = buildVimPluginFrom2Nix { # created by nix#NixDerivation
-      name = "reload";
-      src = fetchgit {
-        url = "git://github.com/xolox/vim-reload";
-        rev = "0a601a668727f5b675cb1ddc19f6861f3f7ab9e1";
-        sha256 = "0vb832l9yxj919f5hfg6qj6bn9ni57gnjd3bj7zpq7d4iv2s4wdh";
-      };
-      dependencies = ["nim-misc"];
-
-    };
-    [...]
-
-Sample output2:
-
-    [
-      ''vim-addon-manager''
-      ''tlib''
-      { "name" = ''vim-addon-sql''; }
-      { "filetype_regex" = ''\%(vim)$$''; "names" = [ ''reload'' ''vim-dev-plugin'' ]; }
-    ]
-
-
-## Important repositories
-
- [vim-pi](https://bitbucket.org/vimcommunity/vim-pi) is a plugin repository
-  from VAM plugin manager meant to be used by others as well used by
-
- [vim2nix](http://github.com/MarcWeber/vim-addon-vim2nix) which generates the
-  .nix code
-
--- a/doc/manual.xml
+++ b/doc/manual.xml
@@ -9,7 +9,7 @@

  </info>

-  <xi:include href="introduction.chapter.xml" />
+  <xi:include href="introduction.xml" />
  <xi:include href="quick-start.xml" />
  <xi:include href="stdenv.xml" />
  <xi:include href="multiple-output.xml" />
@@ -18,7 +18,6 @@
  <xi:include href="functions.xml" />
  <xi:include href="meta.xml" />
  <xi:include href="languages-frameworks/index.xml" />
-  <xi:include href="platform-notes.xml" />
  <xi:include href="package-notes.xml" />
  <xi:include href="overlays.xml" />
  <xi:include href="coding-conventions.xml" />
--- a/doc/meta.xml
+++ b/doc/meta.xml
@@ -53,7 +53,7 @@ $ nix-env -qa hello --json
                "x86_64-linux",
                "armv5tel-linux",
                "armv7l-linux",
-                "mips32-linux",
+                "mips64el-linux",
                "x86_64-darwin",
                "i686-cygwin",
                "i686-freebsd",
@@ -200,9 +200,11 @@ meta-attributes</title>
 meta.platforms = stdenv.lib.platforms.linux;
 </programlisting>

-    Attribute Set <varname>stdenv.lib.platforms</varname> defines
-    <link xlink:href="https://github.com/NixOS/nixpkgs/blob/master/lib/systems/doubles.nix">
-    various common lists</link> of platforms types.</para></listitem>
+    Attribute Set <varname>stdenv.lib.platforms</varname> in
+    <link xlink:href="https://github.com/NixOS/nixpkgs/blob/master/lib/platforms.nix">
+    <filename>nixpkgs/lib/platforms.nix</filename></link> defines various common
+    lists of platforms types.
+    </para></listitem>
  </varlistentry>

  <varlistentry>
--- a/doc/multiple-output.xml
+++ b/doc/multiple-output.xml
@@ -16,6 +16,7 @@

 <section><title>Installing a split package</title>
  <para>When installing a package via <varname>systemPackages</varname> or <command>nix-env</command> you have several options:</para>
+  <warning><para>Currently <command>nix-env</command> almost always installs all outputs until https://github.com/NixOS/nix/pull/815 gets merged.</para></warning>
  <itemizedlist>
    <listitem><para>You can install particular outputs explicitly, as each is available in the Nix language as an attribute of the package.  The <varname>outputs</varname> attribute contains a list of output names.</para></listitem>
    <listitem><para>You can let it use the default outputs.  These are handled by <varname>meta.outputsToInstall</varname> attribute that contains a list of output names.</para>
@@ -68,12 +69,12 @@

      <varlistentry><term><varname>
        $outputDevdoc</varname></term><listitem><para>
-        is for <emphasis>developer</emphasis> documentation.  Currently we count gtk-doc and devhelp books in there.  It goes to <varname>devdoc</varname> or is removed (!) by default.  This is because e.g. gtk-doc tends to be rather large and completely unused by nixpkgs users.
+        is for <emphasis>developer</emphasis> documentation.  Currently we count gtk-doc in there.  It goes to <varname>devdoc</varname> or is removed (!) by default.  This is because e.g. gtk-doc tends to be rather large and completely unused by nixpkgs users.
      </para></listitem></varlistentry>

      <varlistentry><term><varname>
        $outputMan</varname></term><listitem><para>
-        is for man pages (except for section 3). They go to <varname>man</varname> or <varname>$outputBin</varname> by default.
+        is for man pages (except for section 3). They go to <varname>man</varname> or <varname>doc</varname> or <varname>$outputBin</varname> by default.
      </para></listitem></varlistentry>

      <varlistentry><term><varname>
@@ -83,7 +84,7 @@

      <varlistentry><term><varname>
        $outputInfo</varname></term><listitem><para>
-        is for info pages. They go to <varname>info</varname> or <varname>$outputBin</varname> by default.
+        is for info pages. They go to <varname>info</varname> or <varname>doc</varname> or <varname>$outputMan</varname> by default.
      </para></listitem></varlistentry>

    </variablelist>
--- a/doc/overlays.xml
+++ b/doc/overlays.xml
@@ -8,88 +8,59 @@
 overlays. Overlays are used to add layers in the fix-point used by Nixpkgs
 to compose the set of all packages.</para>

-<para>Nixpkgs can be configured with a list of overlays, which are
-applied in order. This means that the order of the overlays can be significant
-if multiple layers override the same package.</para>
-
 <!--============================================================-->

 <section xml:id="sec-overlays-install">
-<title>Installing overlays</title>
+<title>Installing Overlays</title>

-<para>The list of overlays is determined as follows.</para>
-
-<para>If the <varname>overlays</varname> argument is not provided explicitly, we look for overlays in a path. The path
-is determined as follows:
+<para>The set of overlays is looked for in the following places. The
+first one present is considered, and all the rest are ignored:

 <orderedlist>

  <listitem>
-    <para>First, if an <varname>overlays</varname> argument to the nixpkgs function itself is given,
-    then that is used.</para>

-    <para>This can be passed explicitly when importing nipxkgs, for example 
-    <literal>import &lt;nixpkgs> { overlays = [ overlay1 overlay2 ]; }</literal>.</para>
+    <para>As an argument of the imported attribute set. When importing Nixpkgs,
+    the <varname>overlays</varname> attribute argument can be set to a list of
+    functions, which is described in <xref linkend="sec-overlays-layout"/>.</para>
+
  </listitem>

  <listitem>
-    <para>Otherwise, if the Nix path entry <literal>&lt;nixpkgs-overlays></literal> exists, we look for overlays
-    at that path, as described below.</para>

-    <para>See the section on <literal>NIX_PATH</literal> in the Nix manual for more details on how to 
-    set a value for <literal>&lt;nixpkgs-overlays>.</literal></para>
+    <para>In the directory pointed to by the Nix search path entry
+    <literal>&lt;nixpkgs-overlays></literal>.</para>
  </listitem>

  <listitem>
-    <para>If one of <filename>~/.config/nixpkgs/overlays.nix</filename> and
-    <filename>~/.config/nixpkgs/overlays/</filename> exists, then we look for overlays at that path, as
-    described below. It is an error if both exist.</para>
+
+    <para>In the directory <filename>~/.nixpkgs/overlays/</filename>.</para>
  </listitem>

 </orderedlist>
 </para>

-<para>If we are looking for overlays at a path, then there are two cases:
-<itemizedlist>
-  <listitem>
-    <para>If the path is a file, then the file is imported as a Nix expression and used as the list of
-    overlays.</para>
-  </listitem>
+<para>For the second and third options, the directory should contain Nix expressions defining the
+overlays. Each overlay can be a file, a directory containing a
+<filename>default.nix</filename>, or a symlink to one of those. The expressions should follow
+the syntax described in <xref linkend="sec-overlays-layout"/>.</para>

-  <listitem>
-    <para>If the path is a directory, then we take the content of the directory, order it
-    lexicographically, and attempt to interpret each as an overlay by:
-    <itemizedlist>
-      <listitem>
-        <para>Importing the file, if it is a <literal>.nix</literal> file.</para>
-      </listitem>
-      <listitem>
-        <para>Importing a top-level <filename>default.nix</filename> file, if it is a directory.</para>
-      </listitem>
-    </itemizedlist>
-    </para>
-  </listitem>
-</itemizedlist>
-</para>
+<para>The order of the overlay layers can influence the recipe of packages if multiple layers override
+the same recipe. In the case where overlays are loaded from a directory, they are loaded in
+alphabetical order.</para>

-<para>On a NixOS system the value of the <literal>nixpkgs.overlays</literal> option, if present, 
-is passed to the system Nixpkgs directly as an argument. Note that this does not affect the overlays for
-non-NixOS operations (e.g. <literal>nix-env</literal>), which are looked up independently.</para>
-
-<para>The <filename>overlays.nix</filename> option therefore provides a convenient way to use the same
-overlays for a NixOS system configuration and user configuration: the same file can be used
-as <filename>overlays.nix</filename> and imported as the value of <literal>nixpkgs.overlays</literal>.</para>
+<para>To install an overlay using the last option, you can clone the overlay's repository and add
+a symbolic link to it in <filename>~/.nixpkgs/overlays/</filename> directory.</para>

 </section>

 <!--============================================================-->

-<section xml:id="sec-overlays-definition">
-<title>Defining overlays</title>
+<section xml:id="sec-overlays-layout">
+<title>Overlays Layout</title>

-<para>Overlays are Nix functions which accept two arguments, 
-conventionally called <varname>self</varname> and <varname>super</varname>, 
-and return a set of packages. For example, the following is a valid overlay.</para>
+<para>Overlays are expressed as Nix functions which accept 2 arguments and return a set of
+packages.</para>

 <programlisting>
 self: super:
@@ -104,31 +75,25 @@ self: super:
 }
 </programlisting>

-<para>The first argument (<varname>self</varname>) corresponds to the final package
+<para>The first argument, usually named <varname>self</varname>, corresponds to the final package
 set. You should use this set for the dependencies of all packages specified in your
 overlay. For example, all the dependencies of <varname>rr</varname> in the example above come
-from <varname>self</varname>, as well as the overridden dependencies used in the
+from <varname>self</varname>, as well as the overriden dependencies used in the
 <varname>boost</varname> override.</para>

-<para>The second argument (<varname>super</varname>)
+<para>The second argument, usually named <varname>super</varname>,
 corresponds to the result of the evaluation of the previous stages of
 Nixpkgs. It does not contain any of the packages added by the current
-overlay, nor any of the following overlays. This set should be used either
+overlay nor any of the following overlays. This set should be used either
 to refer to packages you wish to override, or to access functions defined
 in Nixpkgs. For example, the original recipe of <varname>boost</varname>
 in the above example, comes from <varname>super</varname>, as well as the
 <varname>callPackage</varname> function.</para>

 <para>The value returned by this function should be a set similar to
-<filename>pkgs/top-level/all-packages.nix</filename>, containing
+<filename>pkgs/top-level/all-packages.nix</filename>, which contains
 overridden and/or new packages.</para>

-<para>Overlays are similar to other methods for customizing Nixpkgs, in particular
-the <literal>packageOverrides</literal> attribute described in <xref linkend="sec-modify-via-packageOverrides"/>.
-Indeed, <literal>packageOverrides</literal> acts as an overlay with only the 
-<varname>super</varname> argument. It is therefore appropriate for basic use, 
-but overlays are more powerful and easier to distribute.</para>
-
 </section>

 </chapter>
--- a/doc/overrides.css
+++ b/doc/overrides.css
@@ -1,8 +0,0 @@
-
-.programlisting img {
-    width: 1em;
-}
-
-.calloutlist img {
-    width: 1.5em;
-}
--- a/doc/package-notes.xml
+++ b/doc/package-notes.xml
@@ -101,7 +101,7 @@ modulesTree = [kernel]
 $ nix-env -i ncurses
 $ export NIX_CFLAGS_LINK=-lncurses
 $ make menuconfig ARCH=<replaceable>arch</replaceable></screen>
-
+          
          </para>
        </listitem>

@@ -111,9 +111,9 @@ $ make menuconfig ARCH=<replaceable>arch</replaceable></screen>
        </listitem>

      </orderedlist>
-
+    
    </para>
-
+    
  </listitem>

  <listitem>
@@ -366,33 +366,15 @@ it. Place the resulting <filename>package.nix</filename> file into

 </section>

-<section xml:id="sec-shell-helpers">
+<section xml:id="sec-autojump">

-<title>Interactive shell helpers</title>
+<title>Autojump</title>

 <para>
-  Some packages provide the shell integration to be more useful. But
-  unlike other systems, nix doesn't have a standard share directory
-  location. This is why a bunch <command>PACKAGE-share</command>
-  scripts are shipped that print the location of the corresponding
-  shared folder.
-
-  Current list of such packages is as following:
-
-  <itemizedlist>
-    <listitem>
-      <para>
-        <literal>autojump</literal>: <command>autojump-share</command>
-      </para>
-    </listitem>
-    <listitem>
-      <para>
-        <literal>fzf</literal>: <command>fzf-share</command>
-      </para>
-    </listitem>
-  </itemizedlist>
-
-  E.g. <literal>autojump</literal> can then used in the .bashrc like this:
+  autojump needs the shell integration to be useful but unlike other systems,
+  nix doesn't have a standard share directory location. This is why a
+  <command>autojump-share</command> script is shipped that prints the location
+  of the shared folder. This can then be used in the .bashrc like this:
 <screen>
  source "$(autojump-share)/autojump.bash"
 </screen>
@@ -409,24 +391,24 @@ it. Place the resulting <filename>package.nix</filename> file into
 <title>Steam in Nix</title>

 <para>
-  Steam is distributed as a <filename>.deb</filename> file, for now only
-  as an i686 package (the amd64 package only has documentation).
-  When unpacked, it has a script called <filename>steam</filename> that
+  Steam is distributed as a <filename>.deb</filename> file, for now only 
+  as an i686 package (the amd64 package only has documentation). 
+  When unpacked, it has a script called <filename>steam</filename> that 
  in ubuntu (their target distro) would go to <filename>/usr/bin
-  </filename>. When run for the first time, this script copies some
-  files to the user's home, which include another script that is the
-  ultimate responsible for launching the steam binary, which is also
+  </filename>. When run for the first time, this script copies some 
+  files to the user's home, which include another script that is the 
+  ultimate responsible for launching the steam binary, which is also 
  in $HOME.
 </para>
 <para>
  Nix problems and constraints:
 <itemizedlist>
-  <listitem><para>We don't have <filename>/bin/bash</filename> and many
+  <listitem><para>We don't have <filename>/bin/bash</filename> and many 
  scripts point there. Similarly for <filename>/usr/bin/python</filename>
  .</para></listitem>
  <listitem><para>We don't have the dynamic loader in <filename>/lib
  </filename>.</para></listitem>
-  <listitem><para>The <filename>steam.sh</filename> script in $HOME can
+  <listitem><para>The <filename>steam.sh</filename> script in $HOME can 
  not be patched, as it is checked and rewritten by steam.</para></listitem>
  <listitem><para>The steam binary cannot be patched, it's also checked.</para></listitem>
 </itemizedlist>
@@ -446,10 +428,10 @@ it. Place the resulting <filename>package.nix</filename> file into
 <title>How to play</title>

 <para>
-  For 64-bit systems it's important to have
-  <programlisting>hardware.opengl.driSupport32Bit = true;</programlisting>
-  in your <filename>/etc/nixos/configuration.nix</filename>. You'll also need
-  <programlisting>hardware.pulseaudio.support32Bit = true;</programlisting>
+  For 64-bit systems it's important to have 
+  <programlisting>hardware.opengl.driSupport32Bit = true;</programlisting> 
+  in your <filename>/etc/nixos/configuration.nix</filename>. You'll also need 
+  <programlisting>hardware.pulseaudio.support32Bit = true;</programlisting> 
  if you are using PulseAudio - this will enable 32bit ALSA apps integration.
  To use the Steam controller, you need to add
  <programlisting>services.udev.extraRules = ''
@@ -470,25 +452,31 @@ it. Place the resulting <filename>package.nix</filename> file into

  <varlistentry>
    <term>Steam fails to start. What do I do?</term>
-    <listitem><para>Try to run
+    <listitem><para>Try to run 
    <programlisting>strace steam</programlisting>
    to see what is causing steam to fail.</para></listitem>
  </varlistentry>

  <varlistentry>
-  <term>Using the FOSS Radeon or nouveau (nvidia) drivers</term>
-  <listitem><itemizedlist>
-    <listitem><para>The <literal>newStdcpp</literal> parameter
-    was removed since NixOS 17.09 and should not be needed anymore.
-    </para></listitem>
-
-    <listitem><para>
-    Steam ships statically linked with a version of libcrypto that
-    conflics with the one dynamically loaded by radeonsi_dri.so.
-    If you get the error
-    <programlisting>steam.sh: line 713: 7842 Segmentation fault (core dumped)</programlisting>
-    have a look at <link xlink:href="https://github.com/NixOS/nixpkgs/pull/20269">this pull request</link>.
-    </para></listitem>
+  <term>Using the FOSS Radeon drivers</term>
+  <listitem><itemizedlist><listitem><para>
+  The open source radeon drivers need a newer libc++ than is provided 
+  by the default runtime, which leads to a crash on launch. Use
+  <programlisting>environment.systemPackages = [(pkgs.steam.override { newStdcpp = true; })];</programlisting>
+  in your config if you get an error like
+  <programlisting>
+libGL error: unable to load driver: radeonsi_dri.so
+libGL error: driver pointer missing
+libGL error: failed to load driver: radeonsi
+libGL error: unable to load driver: swrast_dri.so
+libGL error: failed to load driver: swrast</programlisting></para></listitem>
+  <listitem><para>
+  Steam ships statically linked with a version of libcrypto that
+  conflics with the one dynamically loaded by radeonsi_dri.so.
+  If you get the error
+  <programlisting>steam.sh: line 713: 7842 Segmentation fault (core dumped)</programlisting>
+  have a look at <link xlink:href="https://github.com/NixOS/nixpkgs/pull/20269">this pull request</link>.
+  </para></listitem>

  </itemizedlist></listitem></varlistentry>

@@ -498,7 +486,7 @@ it. Place the resulting <filename>package.nix</filename> file into
  <listitem><para>
  There is no java in steam chrootenv by default. If you get a message like
  <programlisting>/home/foo/.local/share/Steam/SteamApps/common/towns/towns.sh: line 1: java: command not found</programlisting>
-  You need to add
+  You need to add  
  <programlisting> steam.override { withJava = true; };</programlisting>
  to your configuration.
  </para></listitem>
@@ -513,14 +501,14 @@ it. Place the resulting <filename>package.nix</filename> file into

 <title>steam-run</title>
 <para>
-The FHS-compatible chroot used for steam can also be used to run
+The FHS-compatible chroot used for steam can also be used to run 
 other linux games that expect a FHS environment.
-To do it, add
+To do it, add 
 <programlisting>pkgs.(steam.override {
          nativeOnly = true;
          newStdcpp = true;
        }).run</programlisting>
-to your configuration, rebuild, and run the game with
+to your configuration, rebuild, and run the game with 
 <programlisting>steam-run ./foo</programlisting>
 </para>

@@ -528,198 +516,4 @@ to your configuration, rebuild, and run the game with

 </section>

-<section xml:id="sec-emacs">
-
-<title>Emacs</title>
-
-<section xml:id="sec-emacs-config">
-
-<title>Configuring Emacs</title>
-
-<para>
-  The Emacs package comes with some extra helpers to make it easier to
-  configure. <varname>emacsWithPackages</varname> allows you to manage
-  packages from ELPA. This means that you will not have to install
-  that packages from within Emacs. For instance, if you wanted to use
-  <literal>company</literal>, <literal>counsel</literal>,
-  <literal>flycheck</literal>, <literal>ivy</literal>,
-  <literal>magit</literal>, <literal>projectile</literal>, and
-  <literal>use-package</literal> you could use this as a
-  <filename>~/.config/nixpkgs/config.nix</filename> override:
-</para>
-
-<screen>
-{
-  packageOverrides = pkgs: with pkgs; {
-    myEmacs = emacsWithPackages (epkgs: (with epkgs.melpaStablePackages; [
-      company
-      counsel
-      flycheck
-      ivy
-      magit
-      projectile
-      use-package
-    ]));
-  }
-}
-</screen>
-
-<para>
-  You can install it like any other packages via <command>nix-env -iA
-  myEmacs</command>. However, this will only install those packages.
-  It will not <literal>configure</literal> them for us. To do this, we
-  need to provide a configuration file. Luckily, it is possible to do
-  this from within Nix! By modifying the above example, we can make
-  Emacs load a custom config file. The key is to create a package that
-  provide a <filename>default.el</filename> file in
-  <filename>/share/emacs/site-start/</filename>. Emacs knows to load
-  this file automatically when it starts.
-</para>
-
-<screen>
-{
-  packageOverrides = pkgs: with pkgs; rec {
-    myEmacsConfig = writeText "default.el" ''
-;; initialize package
-
-(require 'package)
-(package-initialize 'noactivate)
-(eval-when-compile
-  (require 'use-package))
-
-;; load some packages
-
-(use-package company
-  :bind ("&lt;C-tab&gt;" . company-complete)
-  :diminish company-mode
-  :commands (company-mode global-company-mode)
-  :defer 1
-  :config
-  (global-company-mode))
-
-(use-package counsel
-  :commands (counsel-descbinds)
-  :bind (([remap execute-extended-command] . counsel-M-x)
-         ("C-x C-f" . counsel-find-file)
-         ("C-c g" . counsel-git)
-         ("C-c j" . counsel-git-grep)
-         ("C-c k" . counsel-ag)
-         ("C-x l" . counsel-locate)
-         ("M-y" . counsel-yank-pop)))
-
-(use-package flycheck
-  :defer 2
-  :config (global-flycheck-mode))
-
-(use-package ivy
-  :defer 1
-  :bind (("C-c C-r" . ivy-resume)
-         ("C-x C-b" . ivy-switch-buffer)
-         :map ivy-minibuffer-map
-         ("C-j" . ivy-call))
-  :diminish ivy-mode
-  :commands ivy-mode
-  :config
-  (ivy-mode 1))
-
-(use-package magit
-  :defer
-  :if (executable-find "git")
-  :bind (("C-x g" . magit-status)
-         ("C-x G" . magit-dispatch-popup))
-  :init
-  (setq magit-completing-read-function 'ivy-completing-read))
-
-(use-package projectile
-  :commands projectile-mode
-  :bind-keymap ("C-c p" . projectile-command-map)
-  :defer 5
-  :config
-  (projectile-global-mode))
-    '';
-    myEmacs = emacsWithPackages (epkgs: (with epkgs.melpaStablePackages; [
-      (runCommand "default.el" {} ''
-mkdir -p $out/share/emacs/site-lisp
-cp ${myEmacsConfig} $out/share/emacs/site-lisp/default.el
-'')
-      company
-      counsel
-      flycheck
-      ivy
-      magit
-      projectile
-      use-package
-    ]));
-  };
-}
-</screen>
-
-<para>
-  This provides a fairly full Emacs start file. It will load in
-  addition to the user's presonal config. You can always disable it by
-  passing <command>-q</command> to the Emacs command.
-</para>
-
-<para>
-  Sometimes <varname>emacsWithPackages</varname> is not enough, as
-  this package set has some priorities imposed on packages (with
-  the lowest priority assigned to Melpa Unstable, and the highest for
-  packages manually defined in
-  <filename>pkgs/top-level/emacs-packages.nix</filename>). But you
-  can't control this priorities when some package is installed as a
-  dependency. You can override it on per-package-basis, providing all
-  the required dependencies manually - but it's tedious and there is
-  always a possibility that an unwanted dependency will sneak in
-  through some other package. To completely override such a package
-  you can use <varname>overrideScope</varname>.
-</para>
-
-<screen>
-overrides = super: self: rec {
-  haskell-mode = self.melpaPackages.haskell-mode;
-  ...
-};
-((emacsPackagesNgGen emacs).overrideScope overrides).emacsWithPackages (p: with p; [
-  # here both these package will use haskell-mode of our own choice
-  ghc-mod
-  dante
-])
-</screen>
-
-</section>
-
-</section>
-
-<section xml:id="sec-weechat">
-<title>Weechat</title>
-<para>
-Weechat can be configured to include your choice of plugins, reducing its
-closure size from the default configuration which includes all available
-plugins.  To make use of this functionality, install an expression that
-overrides its configuration such as
-<programlisting>weechat.override {configure = {availablePlugins, ...}: {
-    plugins = with availablePlugins; [ python perl ];
-  }
-}</programlisting>
-</para>
-<para>
-The plugins currently available are <literal>python</literal>,
-<literal>perl</literal>, <literal>ruby</literal>, <literal>guile</literal>,
-<literal>tcl</literal> and <literal>lua</literal>.
-</para>
-<para>
-The python plugin allows the addition of extra libraries. For instance,
-the <literal>inotify.py</literal> script in weechat-scripts requires
-D-Bus or libnotify, and the <literal>fish.py</literal> script requires
-pycrypto. To use these scripts, use the <literal>python</literal>
-plugin's <literal>withPackages</literal> attribute:
-<programlisting>weechat.override {configure = {availablePlugins, ...}: {
-    plugins = with availablePlugins; [
-            (python.withPackages (ps: with ps; [ pycrypto python-dbus ]))
-        ];
-    }
-}
-</programlisting>
-</para>
-</section>
 </chapter>
--- a/doc/platform-notes.xml
+++ b/doc/platform-notes.xml
@@ -1,83 +0,0 @@
-<chapter xmlns="http://docbook.org/ns/docbook"
-         xmlns:xlink="http://www.w3.org/1999/xlink"
-         xml:id="chap-platform-nodes">
-
-<title>Platform Notes</title>
-
-<section xml:id="sec-darwin">
-
-<title>Darwin (macOS)</title>
-<para>Some common issues when packaging software for darwin:</para>
-
-<itemizedlist>
-
-  <listitem>
-    <para>
-      The darwin <literal>stdenv</literal> uses clang instead of gcc.
-      When referring to the compiler <varname>$CC</varname> or <command>cc</command>
-      will work in both cases.  Some builds hardcode gcc/g++ in their
-      build scripts, that can usually be fixed with using something
-      like <literal>makeFlags = [ "CC=cc" ];</literal> or by patching
-      the build scripts.
-    </para>
-
-    <programlisting>
-      stdenv.mkDerivation {
-        name = "libfoo-1.2.3";
-        # ...
-        buildPhase = ''
-          $CC -o hello hello.c
-        '';
-      }
-    </programlisting>
-  </listitem>
-
-  <listitem>
-    <para>
-      On darwin libraries are linked using absolute paths, libraries
-      are resolved by their <literal>install_name</literal> at link
-      time.  Sometimes packages won't set this correctly causing the
-      library lookups to fail at runtime.  This can be fixed by adding
-      extra linker flags or by running <command>install_name_tool -id</command>
-      during the <function>fixupPhase</function>.
-    </para>
-
-    <programlisting>
-      stdenv.mkDerivation {
-        name = "libfoo-1.2.3";
-        # ...
-        makeFlags = stdenv.lib.optional stdenv.isDarwin "LDFLAGS=-Wl,-install_name,$(out)/lib/libfoo.dylib";
-      }
-    </programlisting>
-  </listitem>
-
-  <listitem>
-    <para>
-      Some packages assume xcode is available and use <command>xcrun</command>
-      to resolve build tools like <command>clang</command>, etc.
-      This causes errors like <code>xcode-select: error: no developer tools were found at '/Applications/Xcode.app'</code>
-      while the build doesn't actually depend on xcode.
-    </para>
-
-    <programlisting>
-      stdenv.mkDerivation {
-        name = "libfoo-1.2.3";
-        # ...
-        prePatch = ''
-          substituteInPlace Makefile \
-              --replace '/usr/bin/xcrun clang' clang
-        '';
-      }
-    </programlisting>
-
-    <para>
-      The package <literal>xcbuild</literal> can be used to build projects
-      that really depend on Xcode, however projects that build some kind of
-      graphical interface won't work without using Xcode in an impure way.
-    </para>
-  </listitem>
-
-</itemizedlist>
-</section>
-
-</chapter>
--- a/doc/quick-start.xml
+++ b/doc/quick-start.xml
@@ -212,7 +212,7 @@ $ nix-env -f . -iA libfoo</screen>

  <listitem>
    <para>Optionally commit the new package and open a pull request, or send a patch to
-    <literal>https://groups.google.com/forum/#!forum/nix-devel</literal>.</para>
+    <literal>nix-dev@cs.uu.nl</literal>.</para>
  </listitem>


--- a/doc/reviewing-contributions.xml
+++ b/doc/reviewing-contributions.xml
@@ -7,123 +7,123 @@
 <title>Reviewing contributions</title>

 <warning>
-  <para>The following section is a draft and reviewing policy is still being
+  <para>The following section is a draft and reviewing policy is still being 
    discussed.</para>
 </warning>

-<para>The nixpkgs projects receives a fairly high number of contributions via
-  GitHub pull-requests. Reviewing and approving these is an important task and a
+<para>The nixpkgs projects receives a fairly high number of contributions via 
+  GitHub pull-requests. Reviewing and approving these is an important task and a 
  way to contribute to the project.</para>

-<para>The high change rate of nixpkgs make any pull request that is open for
-  long enough subject to conflicts that will require extra work from the
-  submitter or the merger. Reviewing pull requests in a timely manner and being
-  responsive to the comments is the key to avoid these. GitHub provides sort
-  filters that can be used to see the <link
-    xlink:href="https://github.com/NixOS/nixpkgs/pulls?q=is%3Apr+is%3Aopen+sort%3Aupdated-desc">most
-    recently</link> and the <link
-    xlink:href="https://github.com/NixOS/nixpkgs/pulls?q=is%3Apr+is%3Aopen+sort%3Aupdated-asc">least
+<para>The high change rate of nixpkgs make any pull request that is open for 
+  long enough subject to conflicts that will require extra work from the 
+  submitter or the merger. Reviewing pull requests in a timely manner and being 
+  responsive to the comments is the key to avoid these. Github provides sort 
+  filters that can be used to see the <link 
+    xlink:href="https://github.com/NixOS/nixpkgs/pulls?q=is%3Apr+is%3Aopen+sort%3Aupdated-desc">most 
+    recently</link> and the <link 
+    xlink:href="https://github.com/NixOS/nixpkgs/pulls?q=is%3Apr+is%3Aopen+sort%3Aupdated-asc">least 
    recently</link> updated pull-requests.</para>

-<para>When reviewing a pull request, please always be nice and polite.
-  Controversial changes can lead to controversial opinions, but it is important
+<para>When reviewing a pull request, please always be nice and polite. 
+  Controversial changes can lead to controversial opinions, but it is important 
  to respect every community members and their work.</para>

-<para>GitHub provides reactions, they are a simple and quick way to provide
-  feedback to pull-requests or any comments. The thumb-down reaction should be
-  used with care and if possible accompanied with some explanations so the
+<para>GitHub provides reactions, they are a simple and quick way to provide 
+  feedback to pull-requests or any comments. The thumb-down reaction should be 
+  used with care and if possible accompanied with some explanations so the 
  submitter has directions to improve his contribution.</para>

-<para>Pull-requests reviews should include a list of what has been reviewed in a
-  comment, so other reviewers and mergers can know the state of the
+<para>Pull-requests reviews should include a list of what has been reviewed in a 
+  comment, so other reviewers and mergers can know the state of the 
  review.</para>

-<para>All the review template samples provided in this section are generic and
-  meant as examples. Their usage is optional and the reviewer is free to adapt
+<para>All the review template samples provided in this section are generic and 
+  meant as examples. Their usage is optional and the reviewer is free to adapt 
  them to his liking.</para>

 <section><title>Package updates</title>

-<para>A package update is the most trivial and common type of pull-request.
-  These pull-requests mainly consist in updating the version part of the package
+<para>A package update is the most trivial and common type of pull-request. 
+  These pull-requests mainly consist in updating the version part of the package 
  name and the source hash.</para>
-<para>It can happen that non trivial updates include patches or more complex
+<para>It can happen that non trivial updates include patches or more complex 
  changes.</para>

 <para>Reviewing process:</para>

 <itemizedlist>
-  <listitem><para>Add labels to the pull-request. (Requires commit
+  <listitem><para>Add labels to the pull-request. (Requires commit 
      rights)</para>
    <itemizedlist>
-      <listitem><para><literal>8.has: package (update)</literal> and any topic
+      <listitem><para><literal>8.has: package (update)</literal> and any topic 
          label that fit the updated package.</para></listitem>
    </itemizedlist>
  </listitem>
-  <listitem><para>Ensure that the package versioning is fitting the
+  <listitem><para>Ensure that the package versioning is fitting the 
      guidelines.</para></listitem>
-  <listitem><para>Ensure that the commit text is fitting the
+  <listitem><para>Ensure that the commit text is fitting the 
      guidelines.</para></listitem>
  <listitem><para>Ensure that the package maintainers are notified.</para>
    <itemizedlist>
-      <listitem><para>mention-bot usually notify GitHub users based on the
-          submitted changes, but it can happen that it misses some of the
+      <listitem><para>mention-bot usually notify GitHub users based on the 
+          submitted changes, but it can happen that it misses some of the 
          package maintainers.</para></listitem>
    </itemizedlist>
  </listitem>
-  <listitem><para>Ensure that the meta field contains correct
+  <listitem><para>Ensure that the meta field contains correct 
      information.</para>
    <itemizedlist>
-      <listitem><para>License can change with version updates, so it should be
+      <listitem><para>License can change with version updates, so it should be 
          checked to be fitting upstream license.</para></listitem>
-      <listitem><para>If the package has no maintainer, a maintainer must be
-          set. This can be the update submitter or a community member that
+      <listitem><para>If the package has no maintainer, a maintainer must be 
+          set. This can be the update submitter or a community member that 
          accepts to take maintainership of the package.</para></listitem>
    </itemizedlist>
  </listitem>
  <listitem><para>Ensure that the code contains no typos.</para></listitem>
  <listitem><para>Building the package locally.</para>
    <itemizedlist>
-      <listitem><para>Pull-requests are often targeted to the master or staging
-          branch so building the pull-request locally as it is submitted can
+      <listitem><para>Pull-requests are often targeted to the master or staging 
+          branch so building the pull-request locally as it is submitted can 
          trigger a large amount of source builds.</para>
-        <para>It is possible to rebase the changes on nixos-unstable or
-          nixpkgs-unstable for easier review by running the following commands
+        <para>It is possible to rebase the changes on nixos-unstable or 
+          nixpkgs-unstable for easier review by running the following commands 
          from a nixpkgs clone.
 <screen>
-$ git remote add channels https://github.com/NixOS/nixpkgs-channels.git <co
+$ git remote add channels https://github.com/NixOS/nixpkgs-channels.git <co 
  xml:id='reviewing-rebase-1' />
 $ git fetch channels nixos-unstable <co xml:id='reviewing-rebase-2' />
 $ git fetch origin pull/PRNUMBER/head <co xml:id='reviewing-rebase-3' />
-$ git rebase --onto nixos-unstable BASEBRANCH FETCH_HEAD <co
+$ git rebase --onto nixos-unstable BASEBRANCH FETCH_HEAD <co 
  xml:id='reviewing-rebase-4' />
 </screen>
        <calloutlist>
          <callout arearefs='reviewing-rebase-1'>
-            <para>This should be done only once to be able to fetch channel
+            <para>This should be done only once to be able to fetch channel 
              branches from the nixpkgs-channels repository.</para>
          </callout>
          <callout arearefs='reviewing-rebase-2'>
            <para>Fetching the nixos-unstable branch.</para>
          </callout>
          <callout arearefs='reviewing-rebase-3'>
-            <para>Fetching the pull-request changes, <varname>PRNUMBER</varname>
-              is the number at the end of the pull-request title and
-              <varname>BASEBRANCH</varname> the base branch of the
+            <para>Fetching the pull-request changes, <varname>PRNUMBER</varname> 
+              is the number at the end of the pull-request title and 
+              <varname>BASEBRANCH</varname> the base branch of the 
              pull-request.</para>
          </callout>
          <callout arearefs='reviewing-rebase-3'>
-            <para>Rebasing the pull-request changes to the nixos-unstable
+            <para>Rebasing the pull-request changes to the nixos-unstable 
              branch.</para>
          </callout>
        </calloutlist>
        </para>
      </listitem>
      <listitem>
-        <para>The <link xlink:href="https://github.com/madjar/nox">nox</link>
-          tool can be used to review a pull-request content in a single command.
-          It doesn't rebase on a channel branch so it might trigger multiple
-          source builds. <varname>PRNUMBER</varname> should be replaced by the
+        <para>The <link xlink:href="https://github.com/madjar/nox">nox</link> 
+          tool can be used to review a pull-request content in a single command. 
+          It doesn't rebase on a channel branch so it might trigger multiple 
+          source builds. <varname>PRNUMBER</varname> should be replaced by the 
          number at the end of the pull-request title.</para>
 <screen>
 $ nix-shell -p nox --run "nox-review -k pr PRNUMBER"
@@ -153,42 +153,42 @@ $ nix-shell -p nox --run "nox-review -k pr PRNUMBER"

 <section><title>New packages</title>

-<para>New packages are a common type of pull-requests. These pull requests
+<para>New packages are a common type of pull-requests. These pull requests 
  consists in adding a new nix-expression for a package.</para>

 <para>Reviewing process:</para>

 <itemizedlist>
-  <listitem><para>Add labels to the pull-request. (Requires commit
+  <listitem><para>Add labels to the pull-request. (Requires commit 
      rights)</para>
    <itemizedlist>
-      <listitem><para><literal>8.has: package (new)</literal> and any topic
+      <listitem><para><literal>8.has: package (new)</literal> and any topic 
          label that fit the new package.</para></listitem>
    </itemizedlist>
  </listitem>
-  <listitem><para>Ensure that the package versioning is fitting the
+  <listitem><para>Ensure that the package versioning is fitting the 
      guidelines.</para></listitem>
-  <listitem><para>Ensure that the commit name is fitting the
+  <listitem><para>Ensure that the commit name is fitting the 
      guidelines.</para></listitem>
-  <listitem><para>Ensure that the meta field contains correct
+  <listitem><para>Ensure that the meta field contains correct 
      information.</para>
    <itemizedlist>
-      <listitem><para>License must be checked to be fitting upstream
+      <listitem><para>License must be checked to be fitting upstream 
          license.</para></listitem>
-      <listitem><para>Platforms should be set or the package will not get binary
+      <listitem><para>Platforms should be set or the package will not get binary 
          substitutes.</para></listitem>
-      <listitem><para>A maintainer must be set, this can be the package
-          submitter or a community member that accepts to take maintainership of
+      <listitem><para>A maintainer must be set, this can be the package 
+          submitter or a community member that accepts to take maintainership of 
          the package.</para></listitem>
    </itemizedlist>
  </listitem>
  <listitem><para>Ensure that the code contains no typos.</para></listitem>
  <listitem><para>Ensure the package source.</para>
    <itemizedlist>
-      <listitem><para>Mirrors urls should be used when
+      <listitem><para>Mirrors urls should be used when 
          available.</para></listitem>
-      <listitem><para>The most appropriate function should be used (e.g.
-          packages from GitHub should use
+      <listitem><para>The most appropriate function should be used (e.g. 
+          packages from GitHub should use 
          <literal>fetchFromGitHub</literal>).</para></listitem>
    </itemizedlist>
  </listitem>
@@ -223,49 +223,49 @@ $ nix-shell -p nox --run "nox-review -k pr PRNUMBER"

 <section><title>Module updates</title>

-<para>Module updates are submissions changing modules in some ways. These often
+<para>Module updates are submissions changing modules in some ways. These often 
  contains changes to the options or introduce new options.</para>

 <para>Reviewing process</para>

 <itemizedlist>
-  <listitem><para>Add labels to the pull-request. (Requires commit
+  <listitem><para>Add labels to the pull-request. (Requires commit 
      rights)</para>
    <itemizedlist>
-      <listitem><para><literal>8.has: module (update)</literal> and any topic
+      <listitem><para><literal>8.has: module (update)</literal> and any topic 
          label that fit the module.</para></listitem>
    </itemizedlist>
  </listitem>
  <listitem><para>Ensure that the module maintainers are notified.</para>
    <itemizedlist>
-      <listitem><para>Mention-bot notify GitHub users based on the submitted
-          changes, but it can happen that it miss some of the package
+      <listitem><para>Mention-bot notify GitHub users based on the submitted 
+          changes, but it can happen that it miss some of the package 
          maintainers.</para></listitem>
    </itemizedlist>
  </listitem>
-  <listitem><para>Ensure that the module tests, if any, are
+  <listitem><para>Ensure that the module tests, if any, are 
      succeeding.</para></listitem>
  <listitem><para>Ensure that the introduced options are correct.</para>
    <itemizedlist>
-      <listitem><para>Type should be appropriate (string related types differs
-          in their merging capabilities, <literal>optionSet</literal> and
+      <listitem><para>Type should be appropriate (string related types differs 
+          in their merging capabilities, <literal>optionSet</literal> and 
          <literal>string</literal> types are deprecated).</para></listitem>
-      <listitem><para>Description, default and example should be
+      <listitem><para>Description, default and example should be 
          provided.</para></listitem>
    </itemizedlist>
  </listitem>
  <listitem><para>Ensure that option changes are backward compatible.</para>
    <itemizedlist>
-      <listitem><para><literal>mkRenamedOptionModule</literal> and
-          <literal>mkAliasOptionModule</literal> functions provide way to make
+      <listitem><para><literal>mkRenamedOptionModule</literal> and 
+          <literal>mkAliasOptionModule</literal> functions provide way to make 
          option changes backward compatible.</para></listitem>
    </itemizedlist>
  </listitem>
-  <listitem><para>Ensure that removed options are declared with
+  <listitem><para>Ensure that removed options are declared with 
      <literal>mkRemovedOptionModule</literal></para></listitem>
-  <listitem><para>Ensure that changes that are not backward compatible are
+  <listitem><para>Ensure that changes that are not backward compatible are 
      mentioned in release notes.</para></listitem>
-  <listitem><para>Ensure that documentations affected by the change is
+  <listitem><para>Ensure that documentations affected by the change is 
      updated.</para></listitem>
 </itemizedlist>

@@ -294,37 +294,37 @@ $ nix-shell -p nox --run "nox-review -k pr PRNUMBER"
 <para>New modules submissions introduce a new module to NixOS.</para>

 <itemizedlist>
-  <listitem><para>Add labels to the pull-request. (Requires commit
+  <listitem><para>Add labels to the pull-request. (Requires commit 
      rights)</para>
    <itemizedlist>
-      <listitem><para><literal>8.has: module (new)</literal> and any topic label
+      <listitem><para><literal>8.has: module (new)</literal> and any topic label 
          that fit the module.</para></listitem>
    </itemizedlist>
  </listitem>
-  <listitem><para>Ensure that the module tests, if any, are
+  <listitem><para>Ensure that the module tests, if any, are 
      succeeding.</para></listitem>
  <listitem><para>Ensure that the introduced options are correct.</para>
    <itemizedlist>
-      <listitem><para>Type should be appropriate (string related types differs
-          in their merging capabilities, <literal>optionSet</literal> and
+      <listitem><para>Type should be appropriate (string related types differs 
+          in their merging capabilities, <literal>optionSet</literal> and 
          <literal>string</literal> types are deprecated).</para></listitem>
-      <listitem><para>Description, default and example should be
+      <listitem><para>Description, default and example should be 
          provided.</para></listitem>
    </itemizedlist>
  </listitem>
-  <listitem><para>Ensure that module <literal>meta</literal> field is
+  <listitem><para>Ensure that module <literal>meta</literal> field is 
      present</para>
    <itemizedlist>
-      <listitem><para>Maintainers should be declared in
+      <listitem><para>Maintainers should be declared in 
          <literal>meta.maintainers</literal>.</para></listitem>
-      <listitem><para>Module documentation should be declared with
+      <listitem><para>Module documentation should be declared with 
          <literal>meta.doc</literal>.</para></listitem>
    </itemizedlist>
  </listitem>
-  <listitem><para>Ensure that the module respect other modules
+  <listitem><para>Ensure that the module respect other modules 
      functionality.</para>
    <itemizedlist>
-      <listitem><para>For example, enabling a module should not open firewall
+      <listitem><para>For example, enabling a module should not open firewall 
          ports by default.</para></listitem>
    </itemizedlist>
  </listitem>
@@ -340,7 +340,7 @@ $ nix-shell -p nox --run "nox-review -k pr PRNUMBER"
 - [ ] options have default
 - [ ] options have example
 - [ ] options have descriptions
- [ ] No unneeded package is added to environment.systemPackages
+- [ ] No unneeded package is added to system.environmentPackages
 - [ ] meta.maintainers is set
 - [ ] module documentation is declared in meta.doc

@@ -355,22 +355,22 @@ $ nix-shell -p nox --run "nox-review -k pr PRNUMBER"

 <para>Other type of submissions requires different reviewing steps.</para>

-<para>If you consider having enough knowledge and experience in a topic and
-  would like to be a long-term reviewer for related submissions, please contact
-  the current reviewers for that topic. They will give you information about the
+<para>If you consider having enough knowledge and experience in a topic and 
+  would like to be a long-term reviewer for related submissions, please contact 
+  the current reviewers for that topic. They will give you information about the 
  reviewing process.
-The main reviewers for a topic can be hard to find as there is no list, but
-checking past pull-requests to see who reviewed or git-blaming the code to see
+The main reviewers for a topic can be hard to find as there is no list, but 
+checking past pull-requests to see who reviewed or git-blaming the code to see 
 who committed to that topic can give some hints.</para>

-<para>Container system, boot system and library changes are some examples of the
+<para>Container system, boot system and library changes are some examples of the 
  pull requests fitting this category.</para>

 </section>

 <section><title>Merging pull-requests</title>

-<para>It is possible for community members that have enough knowledge and
+<para>It is possible for community members that have enough knowledge and 
  experience on a special topic to contribute by merging pull requests.</para>

 <para>TODO: add the procedure to request merging rights.</para>
@@ -380,13 +380,13 @@ The following paragraph about how to deal with unactive contributors is just a
 proposition and should be modified to what the community agrees to be the right
 policy.

-<para>Please note that contributors with commit rights unactive for more than
+<para>Please note that contributors with commit rights unactive for more than 
  three months will have their commit rights revoked.</para>
 -->

-<para>In a case a contributor leaves definitively the Nix community, he should
-  create an issue or notify the mailing list with references of packages and
-  modules he maintains so the maintainership can be taken over by other
+<para>In a case a contributor leaves definitively the Nix community, he should 
+  create an issue or notify the mailing list with references of packages and 
+  modules he maintains so the maintainership can be taken over by other 
  contributors.</para>

 </section>
--- a/doc/shell.nix
+++ b/doc/shell.nix
@@ -1,4 +0,0 @@
-{ pkgs ? import ../. {} }:
-(import ./default.nix).overrideAttrs (x: {
-  buildInputs = x.buildInputs ++ [ pkgs.xmloscopy ];
-})
--- a/doc/shell.section.md
+++ b/doc/shell.section.md
@@ -1,22 +0,0 @@
---
-title: pkgs.mkShell
-author: zimbatm
-date: 2017-10-30
---
-
-# mkShell
-
-pkgs.mkShell is a special kind of derivation that is only useful when using
-it combined with nix-shell. It will in fact fail to instantiate when invoked
-with nix-build.
-
-## Usage
-
-```nix
-{ pkgs ? import <nixpkgs> {} }:
-pkgs.mkShell {
-  # this will make all the build inputs from hello and gnutar available to the shell environment
-  inputsFrom = with pkgs; [ hello gnutar ];
-  buildInputs = [ pkgs.gnumake ];
-}
-```
--- a/doc/stdenv.xml
+++ b/doc/stdenv.xml
@@ -179,269 +179,6 @@ genericBuild
 </section>


-<section xml:id="ssec-stdenv-dependencies"><title>Specifying dependencies</title>
-
-<para>
-  As described in the Nix manual, almost any <filename>*.drv</filename> store path in a derivation's attribute set will induce a dependency on that derivation.
-  <varname>mkDerivation</varname>, however, takes a few attributes intended to, between them, include all the dependencies of a package.
-  This is done both for structure and consistency, but also so that certain other setup can take place.
-  For example, certain dependencies need their bin directories added to the <envar>PATH</envar>.
-  That is built-in, but other setup is done via a pluggable mechanism that works in conjunction with these dependency attributes.
-  See <xref linkend="ssec-setup-hooks"/> for details.
-</para>
-<para>
-  Dependencies can be broken down along three axes: their host and target platforms relative to the new derivation's, and whether they are propagated.
-  The platform distinctions are motivated by cross compilation; see <xref linkend="chap-cross"/> for exactly what each platform means.
-  <footnote><para>
-    The build platform is ignored because it is a mere implementation detail of the package satisfying the dependency:
-    As a general programming principle, dependencies are always <emphasis>specified</emphasis> as interfaces, not concrete implementation.
-  </para></footnote>
-  But even if one is not cross compiling, the platforms imply whether or not the dependency is needed at run-time or build-time, a concept that makes perfect sense outside of cross compilation.
-  For now, the run-time/build-time distinction is just a hint for mental clarity, but in the future it perhaps could be enforced.
-</para>
-<para>
-  The extension of <envar>PATH</envar> with dependencies, alluded to above, proceeds according to the relative platforms alone.
-  The process is carried out only for dependencies whose host platform matches the new derivation's build platform–i.e. which run on the platform where the new derivation will be built.
-  <footnote><para>
-    Currently, that means for native builds all dependencies are put on the <envar>PATH</envar>.
-    But in the future that may not be the case for sake of matching cross:
-    the platforms would be assumed to be unique for native and cross builds alike, so only the <varname>depsBuild*</varname> and <varname>nativeBuildDependencies</varname> dependencies would affect the <envar>PATH</envar>.
-  </para></footnote>
-  For each dependency <replaceable>dep</replaceable> of those dependencies, <filename><replaceable>dep</replaceable>/bin</filename>, if present, is added to the <envar>PATH</envar> environment variable.
-</para>
-<para>
-  The dependency is propagated when it forces some of its other-transitive (non-immediate) downstream dependencies to also take it on as an immediate dependency.
-  Nix itself already takes a package's transitive dependencies into account, but this propagation ensures nixpkgs-specific infrastructure like setup hooks (mentioned above) also are run as if the propagated dependency.
-</para>
-<para>
-  It is important to note dependencies are not necessary propagated as the same sort of dependency that they were before, but rather as the corresponding sort so that the platform rules still line up.
-  The exact rules for dependency propagation can be given by assigning each sort of dependency two integers based one how it's host and target platforms are offset from the depending derivation's platforms.
-  Those offsets are given are given below in the descriptions of each dependency list attribute.
-  Algorithmically, we traverse propagated inputs, accumulating every propagated dep's propagated deps and adjusting them to account for the "shift in perspective" described by the current dep's platform offsets.
-  This results in sort a transitive closure of the dependency relation, with the offsets being approximately summed when two dependency links are combined.
-  We also prune transitive deps whose combined offsets go out-of-bounds, which can be viewed as a filter over that transitive closure removing dependencies that are blatantly absurd.
-</para>
-<para>
-  We can define the process precisely with <link xlink:href="https://en.wikipedia.org/wiki/Natural_deduction">Natural Deduction</link> using the inference rules.
-  This probably seems a bit obtuse, but so is the bash code that actually implements it!
-  <footnote><para>
-    The <function>findInputs</function> function, currently residing in <filename>pkgs/stdenv/generic/setup.sh</filename>, implements the propagation logic.
-  </para></footnote>
-  They're confusing in very different ways so...hopefully if something doesn't make sense in one presentation, it does in the other!
-  <programlisting>
-let mapOffset(h, t, i) = i + (if i &lt;= 0 then h else t - 1)
-
-propagated-dep(h0, t0, A, B)
-propagated-dep(h1, t1, B, C)
-h0 + h1 in {-1, 0, 1}
-h0 + t1 in {-1, 0, 1}
-------------------------------------- Transitive property
-propagated-dep(mapOffset(h0, t0, h1),
-               mapOffset(h0, t0, t1),
-               A, C)</programlisting>
-  <programlisting>
-let mapOffset(h, t, i) = i + (if i &lt;= 0 then h else t - 1)
-
-dep(h0, _, A, B)
-propagated-dep(h1, t1, B, C)
-h0 + h1 in {-1, 0, 1}
-h0 + t1 in {-1, 0, -1}
-------------------------------------- Take immediate deps' propagated deps
-propagated-dep(mapOffset(h0, t0, h1),
-               mapOffset(h0, t0, t1),
-               A, C)</programlisting>
-  <programlisting>
-propagated-dep(h, t, A, B)
-------------------------------------- Propagated deps count as deps
-dep(h, t, A, B)</programlisting>
-  Some explanation of this monstrosity is in order.
-  In the common case, the target offset of a dependency is the successor to the target offset: <literal>t = h + 1</literal>.
-  That means that:
-  <programlisting>
-let f(h, t, i) = i + (if i &lt;= 0 then h else t - 1)
-let f(h, h + 1, i) = i + (if i &lt;= 0 then h else (h + 1) - 1)
-let f(h, h + 1, i) = i + (if i &lt;= 0 then h else h)
-let f(h, h + 1, i) = i + h
-  </programlisting>
-  This is where the "sum-like" comes from above:
-  We can just sum all the host offset to get the host offset of the transitive dependency.
-  The target offset is the transitive dep is simply the host offset + 1, just as it was with the dependencies composed to make this transitive one;
-  it can be ignored as it doesn't add any new information.
-</para>
-<para>
-  Because of the bounds checks, the uncommon cases are <literal>h = t</literal> and <literal>h + 2 = t</literal>.
-  In the former case, the motivation for <function>mapOffset</function> is that since its host and target platforms are the same, no transitive dep of it should be able to "discover" an offset greater than its reduced target offsets.
-  <function>mapOffset</function> effectively "squashes" all its transitive dependencies' offsets so that none will ever be greater than the target offset of the original <literal>h = t</literal> package.
-  In the other case, <literal>h + 1</literal> is skipped over between the host and target offsets.
-  Instead of squashing the offsets, we need to "rip" them apart so no transitive dependencies' offset is that one.
-</para>
-<para>
-Overall, the unifying theme here is that propagation shouldn't be introducing transitive dependencies involving platforms the needing package is unaware of.
-The offset bounds checking and definition of <function>mapOffset</function> together ensure that this is the case.
-Discovering a new offset is discovering a new platform, and since those platforms weren't in the derivation "spec" of the needing package, they cannot be relevant.
-From a capability perspective, we can imagine that the host and target platforms of a package are the capabilities a package requires, and the depending package must provide the capability to the dependency.
-</para>
-
-<variablelist>
-  <title>Variables specifying dependencies</title>
-
-   <varlistentry>
-     <term><varname>depsBuildBuild</varname></term>
-     <listitem>
-       <para>
-         A list of dependencies whose host and target platforms are the new derivation's build platform.
-         This means a <literal>-1</literal> host and <literal>-1</literal> target offset from the new derivation's platforms.
-         They are programs/libraries used at build time that furthermore produce programs/libraries also used at build time.
-         If the dependency doesn't care about the target platform (i.e. isn't a compiler or similar tool), put it in <varname>nativeBuildInputs</varname>instead.
-         The most common use for this <literal>buildPackages.stdenv.cc</literal>, the default C compiler for this role.
-         That example crops up more than one might think in old commonly used C libraries.
-       </para>
-       <para>
-         Since these packages are able to be run at build time, that are always added to the <envar>PATH</envar>, as described above.
-         But since these packages are only guaranteed to be able to run then, they shouldn't persist as run-time dependencies.
-         This isn't currently enforced, but could be in the future.
-       </para>
-     </listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><varname>nativeBuildInputs</varname></term>
-    <listitem>
-      <para>
-        A list of dependencies whose host platform is the new derivation's build platform, and target platform is the new derivation's host platform.
-        This means a <literal>-1</literal> host offset and <literal>0</literal> target offset from the new derivation's platforms.
-        They are programs/libraries used at build time that, if they are a compiler or similar tool, produce code to run at run time—i.e. tools used to build the new derivation.
-        If the dependency doesn't care about the target platform (i.e. isn't a compiler or similar tool), put it here, rather than in <varname>depsBuildBuild</varname> or <varname>depsBuildTarget</varname>.
-        This would be called <varname>depsBuildHost</varname> but for historical continuity.
-      </para>
-      <para>
-         Since these packages are able to be run at build time, that are added to the <envar>PATH</envar>, as described above.
-         But since these packages only are guaranteed to be able to run then, they shouldn't persist as run-time dependencies.
-         This isn't currently enforced, but could be in the future.
-       </para>
-    </listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><varname>depsBuildTarget</varname></term>
-    <listitem>
-      <para>
-        A list of dependencies whose host platform is the new derivation's build platform, and target platform is the new derivation's target platform.
-        This means a <literal>-1</literal> host offset and <literal>1</literal> target offset from the new derivation's platforms.
-        They are programs used at build time that produce code to run at run with code produced by the depending package.
-        Most commonly, these would tools used to build the runtime or standard library the currently-being-built compiler will inject into any code it compiles.
-        In many cases, the currently-being built compiler is itself employed for that task, but when that compiler won't run (i.e. its build and host platform differ) this is not possible.
-        Other times, the compiler relies on some other tool, like binutils, that is always built separately so the dependency is unconditional.
-      </para>
-      <para>
-        This is a somewhat confusing dependency to wrap ones head around, and for good reason.
-        As the only one where the platform offsets are not adjacent integers, it requires thinking of a bootstrapping stage <emphasis>two</emphasis> away from the current one.
-        It and it's use-case go hand in hand and are both considered poor form:
-        try not to need this sort dependency, and try not avoid building standard libraries / runtimes in the same derivation as the compiler produces code using them.
-        Instead strive to build those like a normal library, using the newly-built compiler just as a normal library would.
-        In short, do not use this attribute unless you are packaging a compiler and are sure it is needed.
-     </para>
-     <para>
-       Since these packages are able to be run at build time, that are added to the <envar>PATH</envar>, as described above.
-       But since these packages only are guaranteed to be able to run then, they shouldn't persist as run-time dependencies.
-       This isn't currently enforced, but could be in the future.
-     </para>
-    </listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><varname>depsHostHost</varname></term>
-    <listitem><para>
-      A list of dependencies whose host and target platforms match the new derivation's host platform.
-      This means a both <literal>0</literal> host offset and <literal>0</literal> target offset from the new derivation's host platform.
-      These are packages used at run-time to generate code also used at run-time.
-      In practice, that would usually be tools used by compilers for metaprogramming/macro systems, or libraries used by the macros/metaprogramming code itself.
-      It's always preferable to use a <varname>depsBuildBuild</varname> dependency in the derivation being built than a <varname>depsHostHost</varname> on the tool doing the building for this purpose.
-    </para></listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><varname>buildInputs</varname></term>
-    <listitem>
-      <para>
-        A list of dependencies whose host platform and target platform match the new derivation's.
-        This means a <literal>0</literal> host offset and <literal>1</literal> target offset from the new derivation's host platform.
-        This would be called <varname>depsHostTarget</varname> but for historical continuity.
-        If the dependency doesn't care about the target platform (i.e. isn't a compiler or similar tool), put it here, rather than in <varname>depsBuildBuild</varname>.
-      </para>
-      <para>
-        These often are programs/libraries used by the new derivation at <emphasis>run</emphasis>-time, but that isn't always the case.
-        For example, the machine code in a statically linked library is only used at run time, but the derivation containing the library is only needed at build time.
-        Even in the dynamic case, the library may also be needed at build time to appease the linker.
-      </para>
-    </listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><varname>depsTargetTarget</varname></term>
-    <listitem><para>
-      A list of dependencies whose host platform matches the new derivation's target platform.
-      This means a <literal>1</literal> offset from the new derivation's platforms.
-      These are packages that run on the target platform, e.g. the standard library or run-time deps of standard library that a compiler insists on knowing about.
-      It's poor form in almost all cases for a package to depend on another from a future stage [future stage corresponding to positive offset].
-      Do not use this attribute unless you are packaging a compiler and are sure it is needed.
-    </para></listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><varname>depsBuildBuildPropagated</varname></term>
-    <listitem><para>
-      The propagated equivalent of <varname>depsBuildBuild</varname>.
-      This perhaps never ought to be used, but it is included for consistency [see below for the others].
-    </para></listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><varname>propagatedNativeBuildInputs</varname></term>
-    <listitem><para>
-      The propagated equivalent of <varname>nativeBuildInputs</varname>.
-      This would be called <varname>depsBuildHostPropagated</varname> but for historical continuity.
-      For example, if package <varname>Y</varname> has <literal>propagatedNativeBuildInputs = [X]</literal>, and package <varname>Z</varname> has <literal>buildInputs = [Y]</literal>, then package <varname>Z</varname> will be built as if it included package <varname>X</varname> in its <varname>nativeBuildInputs</varname>.
-      If instead, package <varname>Z</varname> has <literal>nativeBuildInputs = [Y]</literal>, then <varname>Z</varname> will be built as if it included <varname>X</varname> in the <varname>depsBuildBuild</varname> of package <varname>Z</varname>, because of the sum of the two <literal>-1</literal> host offsets.
-    </para></listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><varname>depsBuildTargetPropagated</varname></term>
-    <listitem><para>
-      The propagated equivalent of <varname>depsBuildTarget</varname>.
-      This is prefixed for the same reason of alerting potential users.
-    </para></listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><varname>depsHostHostPropagated</varname></term>
-    <listitem><para>
-      The propagated equivalent of <varname>depsHostHost</varname>.
-    </para></listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><varname>propagatedBuildInputs</varname></term>
-    <listitem><para>
-      The propagated equivalent of <varname>buildInputs</varname>.
-      This would be called <varname>depsHostTargetPropagated</varname> but for historical continuity.
-    </para></listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><varname>depsTargetTarget</varname></term>
-    <listitem><para>
-      The propagated equivalent of <varname>depsTargetTarget</varname>.
-      This is prefixed for the same reason of alerting potential users.
-    </para></listitem>
-  </varlistentry>
-
-</variablelist>
-
-</section>
-
-
 <section xml:id="ssec-stdenv-attributes"><title>Attributes</title>

 <variablelist>
@@ -450,12 +187,57 @@ From a capability perspective, we can imagine that the host and target platforms

  <varlistentry>
    <term><varname>NIX_DEBUG</varname></term>
+    <listitem><para>If set, <literal>stdenv</literal> will print some
+    debug information during the build.  In particular, the
+    <command>gcc</command> and <command>ld</command> wrapper scripts
+    will print out the complete command line passed to the wrapped
+    tools.</para></listitem>
+  </varlistentry>
+
+</variablelist>
+
+<variablelist>
+  <title>Variables specifying dependencies</title>
+
+  <varlistentry>
+    <term><varname>nativeBuildInputs</varname></term>
    <listitem><para>
-      A natural number indicating how much information to log.
-      If set to 1 or higher, <literal>stdenv</literal> will print moderate debug information during the build.
-      In particular, the <command>gcc</command> and <command>ld</command> wrapper scripts will print out the complete command line passed to the wrapped tools.
-      If set to 6 or higher, the <literal>stdenv</literal> setup script will be run with <literal>set -x</literal> tracing.
-      If set to 7 or higher, the <command>gcc</command> and <command>ld</command> wrapper scripts will also be run with <literal>set -x</literal> tracing.
+      A list of dependencies used by the new derivation at <emphasis>build</emphasis>-time.
+      I.e. these dependencies should not make it into the package's runtime-closure, though this is currently not checked.
+      For each dependency <replaceable>dir</replaceable>, the directory <filename><replaceable>dir</replaceable>/bin</filename>, if it exists, is added to the <envar>PATH</envar> environment variable.
+      Other environment variables are also set up via a pluggable mechanism.
+      For instance, if <varname>buildInputs</varname> contains Perl, then the <filename>lib/site_perl</filename> subdirectory of each input is added to the <envar>PERL5LIB</envar> environment variable.
+      See <xref linkend="ssec-setup-hooks"/> for details.
+    </para></listitem>
+  </varlistentry>
+
+  <varlistentry>
+    <term><varname>buildInputs</varname></term>
+    <listitem><para>
+      A list of dependencies used by the new derivation at <emphasis>run</emphasis>-time.
+      Currently, the build-time environment is modified in the exact same way as with <varname>nativeBuildInputs</varname>.
+      This is problematic in that when cross-compiling, foreign executables can clobber native ones on the <envar>PATH</envar>.
+      Even more confusing is static-linking.
+      A statically-linked library should be listed here because ultimately that generated machine code will be used at run-time, even though a derivation containing the object files or static archives will only be used at build-time.
+      A less confusing solution to this would be nice.
+    </para></listitem>
+  </varlistentry>
+
+
+  <varlistentry>
+    <term><varname>propagatedNativeBuildInputs</varname></term>
+    <listitem><para>
+      Like <varname>nativeBuildInputs</varname>, but these dependencies are <emphasis>propagated</emphasis>:
+      that is, the dependencies listed here are added to the <varname>nativeBuildInputs</varname> of any package that uses <emphasis>this</emphasis> package as a dependency.
+      So if package Y has <literal>propagatedBuildInputs = [X]</literal>, and package Z has <literal>buildInputs = [Y]</literal>, then package X will appear in Z’s build environment automatically.
+    </para></listitem>
+  </varlistentry>
+
+  <varlistentry>
+    <term><varname>propagatedBuildInputs</varname></term>
+    <listitem><para>
+      Like <varname>buildInputs</varname>, but propagated just like <varname>propagatedNativeBuildInputs</varname>.
+      This inherits <varname>buildInputs</varname>'s flaws of clobbering native executables when cross-compiling and being confusing for static linking.
    </para></listitem>
  </varlistentry>

@@ -466,17 +248,10 @@ From a capability perspective, we can imagine that the host and target platforms

  <varlistentry>
    <term><varname>enableParallelBuilding</varname></term>
-    <listitem>
-      <para>If set to <literal>true</literal>, <literal>stdenv</literal> will
-      pass specific flags to <literal>make</literal> and other build tools to
-      enable parallel building with up to <literal>build-cores</literal>
-      workers.</para>
-
-      <para>Unless set to <literal>false</literal>, some build systems with good
-      support for parallel building including <literal>cmake</literal>,
-      <literal>meson</literal>, and <literal>qmake</literal> will set it to
-      <literal>true</literal>.</para>
-    </listitem>
+    <listitem><para>If set, <literal>stdenv</literal> will pass specific
+    flags to <literal>make</literal> and other build tools to enable
+    parallel building with up to <literal>build-cores</literal>
+    workers.</para></listitem>
  </varlistentry>

  <varlistentry>
@@ -543,13 +318,7 @@ containing some shell commands to be executed, or by redefining the
 shell function
 <varname><replaceable>name</replaceable>Phase</varname>.  The former
 is convenient to override a phase from the derivation, while the
-latter is convenient from a build script.
-
-However, typically one only wants to <emphasis>add</emphasis> some
-commands to a phase, e.g. by defining <literal>postInstall</literal>
-or <literal>preFixup</literal>, as skipping some of the default actions
-may have unexpected consequences.
-</para>
+latter is convenient from a build script.</para>


 <section xml:id="ssec-controlling-phases"><title>Controlling
@@ -865,16 +634,6 @@ script) if it exists.</para>
    true.</para></listitem>
  </varlistentry>

-  <varlistentry>
-    <term><varname>configurePlatforms</varname></term>
-    <listitem><para>
-      By default, when cross compiling, the configure script has <option>--build=...</option> and <option>--host=...</option> passed.
-      Packages can instead pass <literal>[ "build" "host" "target" ]</literal> or a subset to control exactly which platform flags are passed.
-      Compilers and other tools should use this to also pass the target platform, for example.
-      <footnote><para>Eventually these will be passed when in native builds too, to improve determinism: build-time guessing, as is done today, is a risk of impurity.</para></footnote>
-    </para></listitem>
-  </varlistentry>
-
  <varlistentry>
    <term><varname>preConfigure</varname></term>
    <listitem><para>Hook executed at the start of the configure
@@ -921,14 +680,8 @@ nothing.</para>
    <listitem><para>A list of strings passed as additional flags to
    <command>make</command>.  These flags are also used by the default
    install and check phase.  For setting make flags specific to the
-    build phase, use <varname>buildFlags</varname> (see below).
-
-<programlisting>
-makeFlags = [ "PREFIX=$(out)" ];
-</programlisting>
-
-    <note><para>The flags are quoted in bash, but environment variables can
-    be specified by using the make syntax.</para></note></para></listitem>
+    build phase, use <varname>buildFlags</varname> (see
+    below).</para></listitem>
  </varlistentry>

  <varlistentry>
@@ -995,14 +748,13 @@ but only if the <varname>doCheck</varname> variable is enabled.</para>

  <varlistentry>
    <term><varname>doCheck</varname></term>
-    <listitem><para>
-      Controls whether the check phase is executed.
-      By default it is skipped, but if <varname>doCheck</varname> is set to true, the check phase is usually executed.
-      Thus you should set <programlisting>doCheck = true;</programlisting> in the derivation to enable checks.
-      The exception is cross compilation.
-      Cross compiled builds never run tests, no matter how <varname>doCheck</varname> is set,
-      as the newly-built program won't run on the platform used to build it.
-    </para></listitem>
+    <listitem><para>If set to a non-empty string, the check phase is
+    executed, otherwise it is skipped (default).  Thus you should set
+
+    <programlisting>
+doCheck = true;</programlisting>
+
+    in the derivation to enable checks.</para></listitem>
  </varlistentry>

  <varlistentry>
@@ -1139,20 +891,6 @@ following:
    <listitem><para>If set, libraries and executables are not
    stripped.  By default, they are.</para></listitem>
  </varlistentry>
-  <varlistentry>
-    <term><varname>dontStripHost</varname></term>
-    <listitem><para>
-      Like <varname>dontStripHost</varname>, but only affects the <command>strip</command> command targetting the package's host platform.
-      Useful when supporting cross compilation, but otherwise feel free to ignore.
-    </para></listitem>
-  </varlistentry>
-  <varlistentry>
-    <term><varname>dontStripTarget</varname></term>
-    <listitem><para>
-      Like <varname>dontStripHost</varname>, but only affects the <command>strip</command> command targetting the packages' target platform.
-      Useful when supporting cross compilation, but otherwise feel free to ignore.
-    </para></listitem>
-  </varlistentry>

  <varlistentry>
    <term><varname>dontMoveSbin</varname></term>
@@ -1281,14 +1019,12 @@ installcheck</command>.</para>

  <varlistentry>
    <term><varname>doInstallCheck</varname></term>
-    <listitem><para>
-      Controls whether the installCheck phase is executed.
-      By default it is skipped, but if <varname>doInstallCheck</varname> is set to true, the installCheck phase is usually executed.
-      Thus you should set <programlisting>doInstallCheck = true;</programlisting> in the derivation to enable install checks.
-      The exception is cross compilation.
-      Cross compiled builds never run tests, no matter how <varname>doInstallCheck</varname> is set,
-      as the newly-built program won't run on the platform used to build it.
-    </para></listitem>
+    <listitem><para>If set to a non-empty string, the installCheck phase is
+    executed, otherwise it is skipped (default).  Thus you should set
+
+    <programlisting>doInstallCheck = true;</programlisting>
+
+    in the derivation to enable install checks.</para></listitem>
  </varlistentry>

  <varlistentry>
@@ -1401,7 +1137,7 @@ makeWrapper $out/bin/foo $wrapperfile --prefix PATH : ${lib.makeBinPath [ hello

    </listitem>
  </varlistentry>
-
+  

  <varlistentry xml:id='fun-substitute'>
    <term><function>substitute</function>
@@ -1420,7 +1156,7 @@ makeWrapper $out/bin/foo $wrapperfile --prefix PATH : ${lib.makeBinPath [ hello
            <term><option>--replace</option>
            <replaceable>s1</replaceable>
            <replaceable>s2</replaceable></term>
-            <listitem><para>Replace every occurrence of the string
+            <listitem><para>Replace every occurence of the string
            <replaceable>s1</replaceable> by
            <replaceable>s2</replaceable>.</para></listitem>
          </varlistentry>
@@ -1428,7 +1164,7 @@ makeWrapper $out/bin/foo $wrapperfile --prefix PATH : ${lib.makeBinPath [ hello
          <varlistentry>
            <term><option>--subst-var</option>
            <replaceable>varName</replaceable></term>
-            <listitem><para>Replace every occurrence of
+            <listitem><para>Replace every occurence of
            <literal>@<replaceable>varName</replaceable>@</literal> by
            the contents of the environment variable
            <replaceable>varName</replaceable>.  This is useful for
@@ -1441,7 +1177,7 @@ makeWrapper $out/bin/foo $wrapperfile --prefix PATH : ${lib.makeBinPath [ hello
            <term><option>--subst-var-by</option>
            <replaceable>varName</replaceable>
            <replaceable>s</replaceable></term>
-            <listitem><para>Replace every occurrence of
+            <listitem><para>Replace every occurence of
            <literal>@<replaceable>varName</replaceable>@</literal> by
            the string <replaceable>s</replaceable>.</para></listitem>
          </varlistentry>
@@ -1489,7 +1225,7 @@ substitute ./foo.in ./foo.out \
    <term><function>substituteAll</function>
    <replaceable>infile</replaceable>
    <replaceable>outfile</replaceable></term>
-    <listitem><para>Replaces every occurrence of
+    <listitem><para>Replaces every occurence of
    <literal>@<replaceable>varName</replaceable>@</literal>, where
    <replaceable>varName</replaceable> is any environment variable, in
    <replaceable>infile</replaceable>, writing the result to
@@ -1560,7 +1296,7 @@ someVar=$(stripHash $name)

    </para></listitem>
  </varlistentry>
-
+  

  <varlistentry xml:id='fun-wrapProgram'>
    <term><function>wrapProgram</function>
@@ -1585,127 +1321,24 @@ someVar=$(stripHash $name)

 <section xml:id="ssec-setup-hooks"><title>Package setup hooks</title>

-<para>
-  Nix itself considers a build-time dependency merely something that should previously be built and accessible at build time—packages themselves are on their own to perform any additional setup.
-  In most cases, that is fine, and the downstream derivation can deal with it's own dependencies.
-  But for a few common tasks, that would result in almost every package doing the same sort of setup work---depending not on the package itself, but entirely on which dependencies were used.
-</para>
-<para>
-  In order to alleviate this burden, the <firstterm>setup hook></firstterm>mechanism was written, where any package can include a shell script that [by convention rather than enforcement by Nix], any downstream reverse-dependency will source as part of its build process.
-  That allows the downstream dependency to merely specify its dependencies, and lets those dependencies effectively initialize themselves.
-  No boilerplate mirroring the list of dependencies is needed.
-</para>
-<para>
-  The Setup hook mechanism is a bit of a sledgehammer though: a powerful feature with a broad and indiscriminate area of effect.
-  The combination of its power and implicit use may be expedient, but isn't without costs.
-  Nix itself is unchanged, but the spirit of adding dependencies being effect-free is violated even if the letter isn't.
-  For example, if a derivation path is mentioned more than once, Nix itself doesn't care and simply makes sure the dependency derivation is already built just the same—depending is just needing something to exist, and needing is idempotent.
-  However, a dependency specified twice will have its setup hook run twice, and that could easily change the build environment (though a well-written setup hook will therefore strive to be idempotent so this is in fact not observable).
-  More broadly, setup hooks are anti-modular in that multiple dependencies, whether the same or different, should not interfere and yet their setup hooks may well do so.
-</para>
-<para>
-  The most typical use of the setup hook is actually to add other hooks which are then run (i.e. after all the setup hooks) on each dependency.
-  For example, the C compiler wrapper's setup hook feeds itself flags for each dependency that contains relevant libaries and headers.
-  This is done by defining a bash function, and appending its name to one of
-  <envar>envBuildBuildHooks</envar>`,
-  <envar>envBuildHostHooks</envar>`,
-  <envar>envBuildTargetHooks</envar>`,
-  <envar>envHostHostHooks</envar>`,
-  <envar>envHostTargetHooks</envar>`, or
-  <envar>envTargetTargetHooks</envar>`.
-  These 6 bash variables correspond to the 6 sorts of dependencies by platform (there's 12 total but we ignore the propagated/non-propagated axis).
-</para>
-<para>
-  Packages adding a hook should not hard code a specific hook, but rather choose a variable <emphasis>relative</emphasis> to how they are included.
-  Returning to the C compiler wrapper example, if it itself is an <literal>n</literal> dependency, then it only wants to accumulate flags from <literal>n + 1</literal> dependencies, as only those ones match the compiler's target platform.
-  The <envar>hostOffset</envar> variable is defined with the current dependency's host offset <envar>targetOffset</envar> with its target offset, before it's setup hook is sourced.
-  Additionally, since most environment hooks don't care about the target platform,
-  That means the setup hook can append to the right bash array by doing something like
-  <programlisting language="bash">
-addEnvHooks "$hostOffset" myBashFunction
-  </programlisting>
-</para>
-<para>
-  The <emphasis>existence</emphasis> of setups hooks has long been documented and packages inside Nixpkgs are free to use these mechanism.
-  Other packages, however, should not rely on these mechanisms not changing between Nixpkgs versions.
-  Because of the existing issues with this system, there's little benefit from mandating it be stable for any period of time.
-</para>
-<para>
-  Here are some packages that provide a setup hook.
-  Since the mechanism is modular, this probably isn't an exhaustive list.
-  Then again, since the mechanism is only to be used as a last resort, it might be.
+<para>The following packages provide a setup hook:
+
 <variablelist>

  <varlistentry>
-    <term>Bintools Wrapper</term>
-    <listitem>
-      <para>
-        Bintools Wrapper wraps the binary utilities for a bunch of miscellaneous purposes.
-        These are GNU Binutils when targetting Linux, and a mix of cctools and GNU binutils for Darwin.
-        [The "Bintools" name is supposed to be a compromise between "Binutils" and "cctools" not denoting any specific implementation.]
-        Specifically, the underlying bintools package, and a C standard library (glibc or Darwin's libSystem, just for the dynamic loader) are all fed in, and dependency finding, hardening (see below), and purity checks for each are handled by Bintools Wrapper.
-        Packages typically depend on CC Wrapper, which in turn (at run time) depends on Bintools Wrapper.
-      </para>
-      <para>
-        Bintools Wrapper was only just recently split off from CC Wrapper, so the division of labor is still being worked out.
-        For example, it shouldn't care about about the C standard library, but just take a derivation with the dynamic loader (which happens to be the glibc on linux).
-        Dependency finding however is a task both wrappers will continue to need to share, and probably the most important to understand.
-        It is currently accomplished by collecting directories of host-platform dependencies (i.e. <varname>buildInputs</varname> and <varname>nativeBuildInputs</varname>) in environment variables.
-        Bintools Wrapper's setup hook causes any <filename>lib</filename> and <filename>lib64</filename> subdirectories to be added to <envar>NIX_LDFLAGS</envar>.
-        Since CC Wrapper and Bintools Wrapper use the same strategy, most of the Bintools Wrapper code is sparsely commented and refers to CC Wrapper.
-        But CC Wrapper's code, by contrast, has quite lengthy comments.
-        Bintools Wrapper merely cites those, rather than repeating them, to avoid falling out of sync.
-      </para>
-      <para>
-        A final task of the setup hook is defining a number of standard environment variables to tell build systems which executables full-fill which purpose.
-        They are defined to just be the base name of the tools, under the assumption that Bintools Wrapper's binaries will be on the path.
-        Firstly, this helps poorly-written packages, e.g. ones that look for just <command>gcc</command> when <envar>CC</envar> isn't defined yet <command>clang</command> is to be used.
-        Secondly, this helps packages not get confused when cross-compiling, in which case multiple Bintools Wrappers may simultaneously be in use.
-        <footnote><para>
-          Each wrapper targets a single platform, so if binaries for multiple platforms are needed, the underlying binaries must be wrapped multiple times.
-          As this is a property of the wrapper itself, the multiple wrappings are needed whether or not the same underlying binaries can target multiple platforms.
-        </para></footnote>
-        <envar>BUILD_</envar>- and <envar>TARGET_</envar>-prefixed versions of the normal environment variable are defined for the additional Bintools Wrappers, properly disambiguating them.
-      </para>
-      <para>
-        A problem with this final task is that Bintools Wrapper is honest and defines <envar>LD</envar> as <command>ld</command>.
-        Most packages, however, firstly use the C compiler for linking, secondly use <envar>LD</envar> anyways, defining it as the C compiler, and thirdly, only so define <envar>LD</envar> when it is undefined as a fallback.
-        This triple-threat means Bintools Wrapper will break those packages, as LD is already defined as the actual linker which the package won't override yet doesn't want to use.
-        The workaround is to define, just for the problematic package, <envar>LD</envar> as the C compiler.
-        A good way to do this would be <command>preConfigure = "LD=$CC"</command>.
-      </para>
-    </listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term>CC Wrapper</term>
-    <listitem>
-      <para>
-        CC Wrapper wraps a C toolchain for a bunch of miscellaneous purposes.
-        Specifically, a C compiler (GCC or Clang), wrapped binary tools, and a C standard library (glibc or Darwin's libSystem, just for the dynamic loader) are all fed in, and dependency finding, hardening (see below), and purity checks for each are handled by CC Wrapper.
-        Packages typically depend on CC Wrapper, which in turn (at run time) depends on Bintools Wrapper.
-      </para>
-      <para>
-        Dependency finding is undoubtedly the main task of CC Wrapper.
-        This works just like Bintools Wrapper, except that any <filename>include</filename> subdirectory of any relevant dependency is added to <envar>NIX_CFLAGS_COMPILE</envar>.
-        The setup hook itself contains some lengthy comments describing the exact convoluted mechanism by which this is accomplished.
-      </para>
-      <para>
-        CC Wrapper also like Bintools Wrapper defines standard environment variables with the names of the tools it wraps, for the same reasons described above.
-        Importantly, while it includes a <command>cc</command> symlink to the c compiler for portability, the <envar>CC</envar> will be defined using the compiler's "real name" (i.e. <command>gcc</command> or <command>clang</command>).
-        This helps lousy build systems that inspect on the name of the compiler rather than run it.
-      </para>
-    </listitem>
+    <term>GCC wrapper</term>
+    <listitem><para>Adds the <filename>include</filename> subdirectory
+    of each build input to the <envar>NIX_CFLAGS_COMPILE</envar>
+    environment variable, and the <filename>lib</filename> and
+    <filename>lib64</filename> subdirectories to
+    <envar>NIX_LDFLAGS</envar>.</para></listitem>
  </varlistentry>

  <varlistentry>
    <term>Perl</term>
-    <listitem>
-      <para>
-        Adds the <filename>lib/site_perl</filename> subdirectory of each build input to the <envar>PERL5LIB</envar> environment variable.
-        For instance, if <varname>buildInputs</varname> contains Perl, then the <filename>lib/site_perl</filename> subdirectory of each input is added to the <envar>PERL5LIB</envar> environment variable.
-      </para>
-    </listitem>
+    <listitem><para>Adds the <filename>lib/site_perl</filename> subdirectory
+    of each build input to the <envar>PERL5LIB</envar>
+    environment variable.</para></listitem>
  </varlistentry>

  <varlistentry>
@@ -1802,20 +1435,6 @@ addEnvHooks "$hostOffset" myBashFunction
    disabled or patched to work with PaX.</para></listitem>
  </varlistentry>

-  <varlistentry>
-    <term>autoPatchelfHook</term>
-    <listitem><para>This is a special setup hook which helps in packaging
-    proprietary software in that it automatically tries to find missing shared
-    library dependencies of ELF files. All packages within the
-    <envar>runtimeDependencies</envar> environment variable are unconditionally
-    added to executables, which is useful for programs that use
-    <citerefentry>
-      <refentrytitle>dlopen</refentrytitle>
-      <manvolnum>3</manvolnum>
-    </citerefentry>
-    to load libraries at runtime.</para></listitem>
-  </varlistentry>
-
 </variablelist>

 </para>
@@ -1909,7 +1528,7 @@ bin/blib.a(bios_console.o): In function `bios_handle_cup':
    depends on such a format string, it will need to be worked around.
    </para>

-    <para>Additionally, some warnings are enabled which might trigger build
+    <para>Addtionally, some warnings are enabled which might trigger build
    failures if compiler warnings are treated as errors in the package build.
    In this case, set <option>NIX_CFLAGS_COMPILE</option> to
    <option>-Wno-error=warning-type</option>.</para>
@@ -1939,7 +1558,7 @@ fcntl2.h:50:4: error: call to '__open_missing_mode' declared with attribute erro
    <term><varname>pic</varname></term>
    <listitem>
    <para>Adds the <option>-fPIC</option> compiler options. This options adds
-    support for position independent code in shared libraries and thus making
+    support for position independant code in shared libraries and thus making
    ASLR possible.</para>
    <para>Most notably, the Linux kernel, kernel modules and other code
    not running in an operating system environment like boot loaders won't
--- a/doc/style.css
+++ b/doc/style.css
@@ -29,8 +29,8 @@ h2 /* chapters, appendices, subtitle */
 }

 /* Extra space between chapters, appendices. */
-div.chapter > div.titlepage h2, div.appendix > div.titlepage h2
-{
+div.chapter > div.titlepage h2, div.appendix > div.titlepage h2 
+{ 
    margin-top: 1.5em;
 }

@@ -104,7 +104,7 @@ pre.screen, pre.programlisting
    padding: 3px 3px;
    margin-left: 1.5em;
    margin-right: 1.5em;
-
+    color: #600000;
    background: #f4f4f8;
    font-family: monospace;
    border-radius: 0.4em;
@@ -118,6 +118,7 @@ div.example pre.programlisting
    margin: 0 0 0 0;
 }

+
 /***************************************************************************
                               Notes, warnings etc:
 ***************************************************************************/
@@ -171,7 +172,7 @@ div.navfooter *


 /***************************************************************************
-                        Links colors and highlighting:
+                        Links colors and highlighting: 
 ***************************************************************************/

 a { text-decoration: none; }
@@ -208,7 +209,7 @@ tt, code
 .term
 {
    font-weight: bold;
-
+    
 }

 div.variablelist dd p, div.glosslist dd p
@@ -251,4 +252,4 @@ table
 div.affiliation
 {
    font-style: italic;
-}
+}
--- a/doc/submitting-changes.xml
+++ b/doc/submitting-changes.xml
@@ -61,7 +61,7 @@ $ git checkout -b 'fix/pkg-name-update'
 <listitem>
 <para>Format the commit in a following way:</para>
 <programlisting>
-(pkg-name | nixos/&lt;module>): (from -> to | init at version | refactor | etc)
+(pkg-name | service-name): (from -> to | init at version | refactor | etc)
 Additional information.
 </programlisting>

@@ -78,19 +78,19 @@ Additional information.

 <listitem>
 <para>
-<command>firefox: 54.0.1 -> 55.0</command>
+<command>firefox: 3.0 -> 3.1.1</command>
 </para>
 </listitem>

 <listitem>
 <para>
-<command>nixos/hydra: add bazBaz option</command>
+<command>hydra service: add bazBaz option</command>
 </para>
 </listitem>

 <listitem>
 <para>
-<command>nixos/nginx: refactor config generation</command>
+<command>nginx service: refactor config generation</command>
 </para>
 </listitem>
 </itemizedlist>
@@ -196,7 +196,7 @@ Additional information.

 <itemizedlist>
 <listitem>
-<para>Write the title in format <command>(pkg-name | nixos/&lt;module>): improvement</command>.
+<para>Write the title in format <command>(pkg-name | service): improvement</command>.

 <itemizedlist>
 <listitem>
@@ -223,133 +223,6 @@ Additional information.
 </itemizedlist>
 </section>

-<section>
-  <title>Pull Request Template</title>
-  <para>
-    The pull request template helps determine what steps have been made for a
-    contribution so far, and will help guide maintainers on the status of a
-    change. The motivation section of the PR should include any extra details
-    the title does not address and link any existing issues related to the pull
-    request.
-  </para>
-  <para>When a PR is created, it will be pre-populated with some checkboxes detailed below:
-  </para>
-  <section>
-    <title>Tested using sandboxing</title>
-    <para>
-      When sandbox builds are enabled, Nix will setup an isolated environment
-      for each build process. It is used to remove further hidden dependencies
-      set by the build environment to improve reproducibility. This includes
-      access to the network during the build outside of
-      <function>fetch*</function> functions and files outside the Nix store.
-      Depending on the operating system access to other resources are blocked
-      as well (ex. inter process communication is isolated on Linux); see <link
-      xlink:href="https://nixos.org/nix/manual/#description-45">build-use-sandbox</link>
-      in Nix manual for details.
-    </para>
-    <para>
-      Sandboxing is not enabled by default in Nix due to a small performance
-      hit on each build.  In pull requests for <link
-        xlink:href="https://github.com/NixOS/nixpkgs/">nixpkgs</link> people
-      are asked to test builds with sandboxing enabled (see <literal>Tested
-        using sandboxing</literal> in the pull request template) because
-      in<link
-        xlink:href="https://nixos.org/hydra/">https://nixos.org/hydra/</link>
-      sandboxing is also used.
-    </para>
-    <para>
-      Depending if you use NixOS or other platforms you can use one of the
-      following methods to enable sandboxing <emphasis role="bold">before</emphasis> building the package:
-      <itemizedlist>
-        <listitem>
-          <para>
-            <emphasis role="bold">Globally enable sandboxing on NixOS</emphasis>:
-            add the following to 
-            <filename>configuration.nix</filename>
-            <screen>nix.useSandbox = true;</screen>
-          </para>
-        </listitem>
-        <listitem>
-          <para>
-            <emphasis role="bold">Globally enable sandboxing on non-NixOS platforms</emphasis>:
-            add the following to: <filename>/etc/nix/nix.conf</filename>
-            <screen>build-use-sandbox = true</screen>
-          </para>
-        </listitem>
-      </itemizedlist>
-    </para>
-    
-  </section>
-  <section>
-    <title>Built on platform(s)</title>
-    <para>
-      Many Nix packages are designed to run on multiple
-      platforms. As such, it's important to let the maintainer know which
-      platforms your changes have been tested on. It's not always practical to
-      test a change on all platforms, and is not required for a pull request to
-      be merged. Only check the systems you tested the build on in this
-      section.
-    </para>
-  </section>
-  <section>
-    <title>Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)</title>
-    <para>
-      Packages with automated tests are much more likely to be merged in a
-      timely fashion because it doesn't require as much manual testing by the
-      maintainer to verify the functionality of the package. If there are
-      existing tests for the package, they should be run to verify your changes
-      do not break the tests. Tests only apply to packages with NixOS modules
-      defined and can only be run on Linux. For more details on writing and
-      running tests, see the <link
-        xlink:href="https://nixos.org/nixos/manual/index.html#sec-nixos-tests">section
-        in the NixOS manual</link>.
-    </para>
-  </section>
-  <section>
-    <title>Tested compilation of all pkgs that depend on this change using <command>nox-review</command></title>
-    <para>
-      If you are updating a package's version, you can use nox to make sure all
-      packages that depend on the updated package still compile correctly. This
-      can be done using the nox utility. The <command>nox-review</command>
-      utility can look for and build all dependencies either based on
-      uncommited changes with the <literal>wip</literal> option or specifying a
-      github pull request number.
-    </para>
-    <para>
-      review uncommitted changes:
-      <screen>nix-shell -p nox --run nox-review wip</screen>
-    </para>
-    <para>
-      review changes from pull request number 12345:
-      <screen>nix-shell -p nox --run nox-review pr 12345</screen>
-    </para>
-  </section>
-  <section>
-    <title>Tested execution of all binary files (usually in <filename>./result/bin/</filename>)</title>
-    <para>
-      It's important to test any executables generated by a build when you
-      change or create a package in nixpkgs. This can be done by looking in
-      <filename>./result/bin</filename> and running any files in there, or at a
-      minimum, the main executable for the package. For example, if you make a change
-      to <package>texlive</package>, you probably would only check the binaries
-      associated with the change you made rather than testing all of them.
-    </para>
-  </section>
-  <section>
-    <title>Meets nixpkgs contribution standards</title>
-    <para>
-      The last checkbox is fits <link
-        xlink:href="https://github.com/NixOS/nixpkgs/blob/master/.github/CONTRIBUTING.md">CONTRIBUTING.md</link>.
-      The contributing document has detailed information on standards the Nix
-      community has for commit messages, reviews, licensing of contributions
-      you make to the project, etc... Everyone should read and understand the
-      standards the community has for contributing before submitting a pull
-      request.
-    </para>
-    
-  </section>
-</section>
-
 <section>
 <title>Hotfixing pull requests</title>

--- a/lib/attrsets.nix
+++ b/lib/attrsets.nix
@@ -1,12 +1,12 @@
-{ lib }:
 # Operations on attribute sets.

-let
+with {
  inherit (builtins) head tail length;
-  inherit (lib.trivial) and or;
-  inherit (lib.strings) concatStringsSep;
-  inherit (lib.lists) fold concatMap concatLists all deepSeqList;
-in
+  inherit (import ./trivial.nix) or;
+  inherit (import ./default.nix) fold;
+  inherit (import ./strings.nix) concatStringsSep;
+  inherit (import ./lists.nix) concatMap concatLists all deepSeqList;
+};

 rec {
  inherit (builtins) attrNames listToAttrs hasAttr isAttrs getAttr;
@@ -116,7 +116,7 @@ rec {
    listToAttrs (concatMap (name: let v = set.${name}; in if pred name v then [(nameValuePair name v)] else []) (attrNames set));


-  /* Filter an attribute set recursively by removing all attributes for
+  /* Filter an attribute set recursivelly by removing all attributes for
     which the given predicate return false.

     Example:
@@ -334,7 +334,7 @@ rec {
      value = f name (catAttrs name sets);
    }) names);

-  /* Implementation note: Common names  appear multiple times in the list of
+  /* Implentation note: Common names  appear multiple times in the list of
     names, hopefully this does not affect the system because the maximal
     laziness avoid computing twice the same expression and listToAttrs does
     not care about duplicated attribute names.
@@ -353,7 +353,7 @@ rec {
  zipAttrs = zipAttrsWith (name: values: values);

  /* Does the same as the update operator '//' except that attributes are
-     merged until the given predicate is verified.  The predicate should
+     merged until the given pedicate is verified.  The predicate should
     accept 3 arguments which are the path to reach the attribute, a part of
     the first attribute set and a part of the second attribute set.  When
     the predicate is verified, the value of the first attribute set is
@@ -417,15 +417,18 @@ rec {

  /* Returns true if the pattern is contained in the set. False otherwise.

+     FIXME(zimbatm): this example doesn't work !!!
+
     Example:
-       matchAttrs { cpu = {}; } { cpu = { bits = 64; }; }
+       sys = mkSystem { }
+       matchAttrs { cpu = { bits = 64; }; } sys
       => true
   */
-  matchAttrs = pattern: attrs: assert isAttrs pattern;
-    fold and true (attrValues (zipAttrsWithNames (attrNames pattern) (n: values:
+  matchAttrs = pattern: attrs:
+    fold or false (attrValues (zipAttrsWithNames (attrNames pattern) (n: values:
      let pat = head values; val = head (tail values); in
      if length values == 1 then false
-      else if isAttrs pat then isAttrs val && matchAttrs pat val
+      else if isAttrs pat then isAttrs val && matchAttrs head values
      else pat == val
    ) [pattern attrs]));

--- a/lib/composable-derivation.nix
+++ b/lib/composable-derivation.nix
@@ -1,4 +1,4 @@
-{lib, pkgs}:
+{lib, pkgs} :
 let inherit (lib) nv nvs; in
 {

@@ -19,7 +19,7 @@ let inherit (lib) nv nvs; in
  # * vim_configurable
  #
  # A minimal example illustrating most features would look like this:
-  # let base = composableDerivation { (fixed: let inherit (fixed.fixed) name in {
+  # let base = composableDerivation { (fixed : let inherit (fixed.fixed) name in {
  #    src = fetchurl {
  #    }
  #    buildInputs = [A];
@@ -39,7 +39,7 @@ let inherit (lib) nv nvs; in
  #
  # issues:
  # * its complicated to understand
-  # * some "features" such as exact merge behaviour are buried in mergeAttrBy
+  # * some "features" such as exact merge behaviour are burried in mergeAttrBy
  #   and defaultOverridableDelayableArgs assuming the default behaviour does
  #   the right thing in the common case
  # * Eelco once said using such fix style functions are slow to evaluate
@@ -48,7 +48,7 @@ let inherit (lib) nv nvs; in
  #   / add patches the way you want without having to declare function arguments
  #
  # nice features:
-  # declaring "optional features" is modular. For instance:
+  # declaring "optional featuers" is modular. For instance:
  #   flags.curl = {
  #     configureFlags = ["--with-curl=${curl.dev}" "--with-curlwrappers"];
  #     buildInputs = [curl openssl];
@@ -79,7 +79,7 @@ let inherit (lib) nv nvs; in
        # consider adding addtional elements by derivation.merge { removeAttrs = ["elem"]; };
        removeAttrs ? ["cfg" "flags"]

-      }: (lib.defaultOverridableDelayableArgs ( a: mkDerivation a)
+      }: (lib.defaultOverridableDelayableArgs ( a: mkDerivation a) 
         {
           inherit applyPreTidy removeAttrs;
         }).merge;
--- a/lib/customisation.nix
+++ b/lib/customisation.nix
@@ -1,7 +1,7 @@
-{ lib }:
 let

-  inherit (builtins) attrNames;
+  lib = import ./default.nix;
+  inherit (builtins) attrNames isFunction;

 in

@@ -10,7 +10,7 @@ rec {

  /* `overrideDerivation drv f' takes a derivation (i.e., the result
     of a call to the builtin function `derivation') and returns a new
-     derivation in which the attributes of the original are overridden
+     derivation in which the attributes of the original are overriden
     according to the function `f'.  The function `f' is called with
     the original derivation attributes.

@@ -36,7 +36,7 @@ rec {
  overrideDerivation = drv: f:
    let
      newDrv = derivation (drv.drvAttrs // (f drv));
-    in lib.flip (extendDerivation true) newDrv (
+    in addPassthru newDrv (
      { meta = drv.meta or {};
        passthru = if drv ? passthru then drv.passthru else {};
      }
@@ -51,28 +51,10 @@ rec {
       else { }));


-  /* `makeOverridable` takes a function from attribute set to attribute set and
-     injects `override` attibute which can be used to override arguments of
-     the function.
-
-       nix-repl> x = {a, b}: { result = a + b; }
-
-       nix-repl> y = lib.makeOverridable x { a = 1; b = 2; }
-
-       nix-repl> y
-       { override = «lambda»; overrideDerivation = «lambda»; result = 3; }
-
-       nix-repl> y.override { a = 10; }
-       { override = «lambda»; overrideDerivation = «lambda»; result = 12; }
-
-     Please refer to "Nixpkgs Contributors Guide" section
-     "<pkg>.overrideDerivation" to learn about `overrideDerivation` and caveats
-     related to its use.
-  */
  makeOverridable = f: origArgs:
    let
      ff = f origArgs;
-      overrideWith = newArgs: origArgs // (if lib.isFunction newArgs then newArgs origArgs else newArgs);
+      overrideWith = newArgs: origArgs // (if builtins.isFunction newArgs then newArgs origArgs else newArgs);
    in
      if builtins.isAttrs ff then (ff // {
        override = newArgs: makeOverridable f (overrideWith newArgs);
@@ -81,7 +63,7 @@ rec {
        ${if ff ? overrideAttrs then "overrideAttrs" else null} = fdrv:
          makeOverridable (args: (f args).overrideAttrs fdrv) origArgs;
      })
-      else if lib.isFunction ff then {
+      else if builtins.isFunction ff then {
        override = newArgs: makeOverridable f (overrideWith newArgs);
        __functor = self: ff;
        overrideDerivation = throw "overrideDerivation not yet supported for functors";
@@ -112,8 +94,8 @@ rec {
  */
  callPackageWith = autoArgs: fn: args:
    let
-      f = if lib.isFunction fn then fn else import fn;
-      auto = builtins.intersectAttrs (lib.functionArgs f) autoArgs;
+      f = if builtins.isFunction fn then fn else import fn;
+      auto = builtins.intersectAttrs (builtins.functionArgs f) autoArgs;
    in makeOverridable f (auto // args);


@@ -122,8 +104,8 @@ rec {
     individual attributes. */
  callPackagesWith = autoArgs: fn: args:
    let
-      f = if lib.isFunction fn then fn else import fn;
-      auto = builtins.intersectAttrs (lib.functionArgs f) autoArgs;
+      f = if builtins.isFunction fn then fn else import fn;
+      auto = builtins.intersectAttrs (builtins.functionArgs f) autoArgs;
      origArgs = auto // args;
      pkgs = f origArgs;
      mkAttrOverridable = name: pkg: makeOverridable (newArgs: (f newArgs).${name}) origArgs;
@@ -131,8 +113,8 @@ rec {


  /* Add attributes to each output of a derivation without changing
-     the derivation itself and check a given condition when evaluating. */
-  extendDerivation = condition: passthru: drv:
+     the derivation itself. */
+  addPassthru = drv: passthru:
    let
      outputs = drv.outputs or [ "out" ];

@@ -142,18 +124,13 @@ rec {
      outputToAttrListElement = outputName:
        { name = outputName;
          value = commonAttrs // {
-            inherit (drv.${outputName}) type outputName;
-            drvPath = assert condition; drv.${outputName}.drvPath;
-            outPath = assert condition; drv.${outputName}.outPath;
+            inherit (drv.${outputName}) outPath drvPath type outputName;
          };
        };

      outputsList = map outputToAttrListElement outputs;
-    in commonAttrs // {
-      outputUnspecified = true;
-      drvPath = assert condition; drv.drvPath;
-      outPath = assert condition; drv.outPath;
-    };
+  in commonAttrs // { outputUnspecified = true; };
+

  /* Strip a derivation of all non-essential attributes, returning
     only those needed by hydra-eval-jobs. Also strictly evaluate the
@@ -190,7 +167,7 @@ rec {
  /* Make a set of packages with a common scope. All packages called
     with the provided `callPackage' will be evaluated with the same
     arguments. Any package in the set may depend on any other. The
-     `overrideScope' function allows subsequent modification of the package
+     `override' function allows subsequent modification of the package
     set in a consistent way, i.e. all packages in the set will be
     called with the overridden packages. The package sets may be
     hierarchical: the packages in the set are called with the scope
@@ -200,7 +177,7 @@ rec {
    let self = f self // {
          newScope = scope: newScope (self // scope);
          callPackage = self.newScope {};
-          overrideScope = g:
+          override = g:
            makeScope newScope
            (self_: let super = f self_; in super // g super self_);
          packages = f;
--- a/lib/debug.nix
+++ b/lib/debug.nix
@@ -1,11 +1,9 @@
-{ lib }:
+let lib = import ./default.nix;

-let
-
-inherit (builtins) trace attrNamesToStr isAttrs isList isInt
+inherit (builtins) trace attrNamesToStr isAttrs isFunction isList isInt
        isString isBool head substring attrNames;

-inherit (lib) all id mapAttrsFlatten elem isFunction;
+inherit (lib) all id mapAttrsFlatten elem;

 in

@@ -22,38 +20,14 @@ rec {
  traceXMLValMarked = str: x: trace (str + builtins.toXML x) x;

  # strict trace functions (traced structure is fully evaluated and printed)
-
-  /* `builtins.trace`, but the value is `builtins.deepSeq`ed first. */
  traceSeq = x: y: trace (builtins.deepSeq x x) y;
-
-  /* Like `traceSeq`, but only down to depth n.
-   * This is very useful because lots of `traceSeq` usages
-   * lead to an infinite recursion.
-   */
-  traceSeqN = depth: x: y: with lib;
-    let snip = v: if      isList  v then noQuotes "[…]" v
-                  else if isAttrs v then noQuotes "{…}" v
-                  else v;
-        noQuotes = str: v: { __pretty = const str; val = v; };
-        modify = n: fn: v: if (n == 0) then fn v
-                      else if isList  v then map (modify (n - 1) fn) v
-                      else if isAttrs v then mapAttrs
-                        (const (modify (n - 1) fn)) v
-                      else v;
-    in trace (generators.toPretty { allowPrettyValues = true; }
-               (modify depth snip x)) y;
-
-  /* `traceSeq`, but the same value is traced and returned */
  traceValSeq = v: traceVal (builtins.deepSeq v v);
-  /* `traceValSeq` but with fixed depth */
-  traceValSeqN = depth: v: traceSeqN depth v v;
-

  # this can help debug your code as well - designed to not produce thousands of lines
-  traceShowVal = x: trace (showVal x) x;
+  traceShowVal = x : trace (showVal x) x;
  traceShowValMarked = str: x: trace (str + showVal x) x;
-  attrNamesToStr = a: lib.concatStringsSep "; " (map (x: "${x}=") (attrNames a));
-  showVal = x:
+  attrNamesToStr = a : lib.concatStringsSep "; " (map (x : "${x}=") (attrNames a));
+  showVal = x :
      if isAttrs x then
          if x ? outPath then "x is a derivation, name ${if x ? name then x.name else "<no name>"}, { ${attrNamesToStr x} }"
          else "x is attr set { ${attrNamesToStr x} }"
@@ -69,9 +43,9 @@ rec {

  # trace the arguments passed to function and its result
  # maybe rewrite these functions in a traceCallXml like style. Then one function is enough
-  traceCall  = n: f: a: let t = n2: x: traceShowValMarked "${n} ${n2}:" x; in t "result" (f (t "arg 1" a));
-  traceCall2 = n: f: a: b: let t = n2: x: traceShowValMarked "${n} ${n2}:" x; in t "result" (f (t "arg 1" a) (t "arg 2" b));
-  traceCall3 = n: f: a: b: c: let t = n2: x: traceShowValMarked "${n} ${n2}:" x; in t "result" (f (t "arg 1" a) (t "arg 2" b) (t "arg 3" c));
+  traceCall  = n : f : a : let t = n2 : x : traceShowValMarked "${n} ${n2}:" x; in t "result" (f (t "arg 1" a));
+  traceCall2 = n : f : a : b : let t = n2 : x : traceShowValMarked "${n} ${n2}:" x; in t "result" (f (t "arg 1" a) (t "arg 2" b));
+  traceCall3 = n : f : a : b : c : let t = n2 : x : traceShowValMarked "${n} ${n2}:" x; in t "result" (f (t "arg 1" a) (t "arg 2" b) (t "arg 3" c));

  # FIXME: rename this?
  traceValIfNot = c: x:
@@ -97,7 +71,7 @@ rec {

  # create a test assuming that list elements are true
  # usage: { testX = allTrue [ true ]; }
-  testAllTrue = expr: { inherit expr; expected = map (x: true) expr; };
+  testAllTrue = expr : { inherit expr; expected = map (x: true) expr; };

  strict = v:
    trace "Warning: strict is deprecated and will be removed in the next release"
--- a/lib/default.nix
+++ b/lib/default.nix
@@ -1,132 +1,51 @@
-/* Library of low-level helper functions for nix expressions.
- *
- * Please implement (mostly) exhaustive unit tests
- * for new functions in `./tests.nix'.
- */
 let

-  callLibs = file: import file { inherit lib; };
+  # trivial, often used functions
+  trivial = import ./trivial.nix;

-  lib = rec {
+  # datatypes
+  attrsets = import ./attrsets.nix;
+  lists = import ./lists.nix;
+  strings = import ./strings.nix;
+  stringsWithDeps = import ./strings-with-deps.nix;

-    # often used, or depending on very little
-    trivial = callLibs ./trivial.nix;
-    fixedPoints = callLibs ./fixed-points.nix;
+  # packaging
+  customisation = import ./customisation.nix;
+  maintainers = import ./maintainers.nix;
+  meta = import ./meta.nix;
+  sources = import ./sources.nix;

-    # datatypes
-    attrsets = callLibs ./attrsets.nix;
-    lists = callLibs ./lists.nix;
-    strings = callLibs ./strings.nix;
-    stringsWithDeps = callLibs ./strings-with-deps.nix;
+  # module system
+  modules = import ./modules.nix;
+  options = import ./options.nix;
+  types = import ./types.nix;

-    # packaging
-    customisation = callLibs ./customisation.nix;
-    maintainers = import ../maintainers/maintainer-list.nix;
-    meta = callLibs ./meta.nix;
-    sources = callLibs ./sources.nix;
-    versions = callLibs ./versions.nix;
+  # constants
+  licenses = import ./licenses.nix;
+  platforms = import ./platforms.nix;
+  systems = import ./systems.nix;

-    # module system
-    modules = callLibs ./modules.nix;
-    options = callLibs ./options.nix;
-    types = callLibs ./types.nix;
+  # misc
+  debug = import ./debug.nix;
+  generators = import ./generators.nix;
+  misc = import ./deprecated.nix;

-    # constants
-    licenses = callLibs ./licenses.nix;
-    systems = callLibs ./systems;
+  # domain-specific
+  sandbox = import ./sandbox.nix;
+  fetchers = import ./fetchers.nix;

-    # misc
-    debug = callLibs ./debug.nix;
-
-    generators = callLibs ./generators.nix;
-    misc = callLibs ./deprecated.nix;
-    # domain-specific
-    fetchers = callLibs ./fetchers.nix;
-
-    # Eval-time filesystem handling
-    filesystem = callLibs ./filesystem.nix;
-
-    # back-compat aliases
-    platforms = systems.doubles;
-
-    inherit (builtins) add addErrorContext attrNames
-      concatLists deepSeq elem elemAt filter genericClosure genList
-      getAttr hasAttr head isAttrs isBool isInt isList
-      isString length lessThan listToAttrs pathExists readFile
-      replaceStrings seq stringLength sub substring tail;
-    inherit (trivial) id const concat or and boolToString mergeAttrs
-      flip mapNullable inNixShell min max importJSON warn info
-      nixpkgsVersion mod compare splitByAndCompare
-      functionArgs setFunctionArgs isFunction;
-
-    inherit (fixedPoints) fix fix' extends composeExtensions
-      makeExtensible makeExtensibleWithCustomName;
-    inherit (attrsets) attrByPath hasAttrByPath setAttrByPath
-      getAttrFromPath attrVals attrValues catAttrs filterAttrs
-      filterAttrsRecursive foldAttrs collect nameValuePair mapAttrs
-      mapAttrs' mapAttrsToList mapAttrsRecursive mapAttrsRecursiveCond
-      genAttrs isDerivation toDerivation optionalAttrs
-      zipAttrsWithNames zipAttrsWith zipAttrs recursiveUpdateUntil
-      recursiveUpdate matchAttrs overrideExisting getOutput getBin
-      getLib getDev chooseDevOutputs zipWithNames zip;
-    inherit (lists) singleton foldr fold foldl foldl' imap0 imap1
-      concatMap flatten remove findSingle findFirst any all count
-      optional optionals toList range partition zipListsWith zipLists
-      reverseList listDfs toposort sort compareLists take drop sublist
-      last init crossLists unique intersectLists subtractLists
-      mutuallyExclusive;
-    inherit (strings) concatStrings concatMapStrings concatImapStrings
-      intersperse concatStringsSep concatMapStringsSep
-      concatImapStringsSep makeSearchPath makeSearchPathOutput
-      makeLibraryPath makeBinPath makePerlPath optionalString
-      hasPrefix hasSuffix stringToCharacters stringAsChars escape
-      escapeShellArg escapeShellArgs replaceChars lowerChars upperChars
-      toLower toUpper addContextFrom splitString removePrefix
-      removeSuffix versionOlder versionAtLeast getVersion nameFromURL
-      enableFeature fixedWidthString fixedWidthNumber isStorePath
-      toInt readPathsFromFile fileContents;
-    inherit (stringsWithDeps) textClosureList textClosureMap
-      noDepEntry fullDepEntry packEntry stringAfter;
-    inherit (customisation) overrideDerivation makeOverridable
-      callPackageWith callPackagesWith extendDerivation
-      hydraJob makeScope;
-    inherit (meta) addMetaAttrs dontDistribute setName updateName
-      appendToName mapDerivationAttrset lowPrio lowPrioSet hiPrio
-      hiPrioSet;
-    inherit (sources) pathType pathIsDirectory cleanSourceFilter
-      cleanSource sourceByRegex sourceFilesBySuffices
-      commitIdFromGitRepo cleanSourceWith pathHasContext canCleanSource;
-    inherit (modules) evalModules closeModules unifyModuleSyntax
-      applyIfFunction unpackSubmodule packSubmodule mergeModules
-      mergeModules' mergeOptionDecls evalOptionValue mergeDefinitions
-      pushDownProperties dischargeProperties filterOverrides
-      sortProperties fixupOptionType mkIf mkAssert mkMerge mkOverride
-      mkOptionDefault mkDefault mkForce mkVMOverride mkStrict
-      mkFixStrictness mkOrder mkBefore mkAfter mkAliasDefinitions
-      mkAliasAndWrapDefinitions fixMergeModules mkRemovedOptionModule
-      mkRenamedOptionModule mkMergedOptionModule mkChangedOptionModule
-      mkAliasOptionModule doRename filterModules;
-    inherit (options) isOption mkEnableOption mkSinkUndeclaredOptions
-      mergeDefaultOption mergeOneOption mergeEqualOption getValues
-      getFiles optionAttrSetToDocList optionAttrSetToDocList'
-      scrubOptionValue literalExample showOption showFiles
-      unknownModule mkOption;
-    inherit (types) isType setType defaultTypeMerge defaultFunctor
-      isOptionType mkOptionType;
-    inherit (debug) addErrorContextToAttrs traceIf traceVal
-      traceXMLVal traceXMLValMarked traceSeq traceSeqN traceValSeq
-      traceValSeqN traceShowVal traceShowValMarked
-      showVal traceCall traceCall2 traceCall3 traceValIfNot runTests
-      testAllTrue strict traceCallXml attrNamesToStr;
-    inherit (misc) maybeEnv defaultMergeArg defaultMerge foldArgs
-      defaultOverridableDelayableArgs composedArgsAndFun
-      maybeAttrNullable maybeAttr ifEnable checkFlag getValue
-      checkReqs uniqList uniqListExt condConcat lazyGenericClosure
-      innerModifySumArgs modifySumArgs innerClosePropagation
-      closePropagation mapAttrsFlatten nvs setAttr setAttrMerge
-      mergeAttrsWithFunc mergeAttrsConcatenateValues
-      mergeAttrsNoOverride mergeAttrByFunc mergeAttrsByFuncDefaults
-      mergeAttrsByFuncDefaultsClean mergeAttrBy
-      prepareDerivationArgs nixType imap overridableDelayableArgs;
-  };
-in lib
+in
+  { inherit trivial
+            attrsets lists strings stringsWithDeps
+            customisation maintainers meta sources
+            modules options types
+            licenses platforms systems
+            debug generators misc
+            sandbox fetchers;
+  }
+  # !!! don't include everything at top-level; perhaps only the most
+  # commonly used functions.
+  // trivial // lists // strings // stringsWithDeps // attrsets // sources
+  // options // types // meta // debug // misc // modules
+  // systems
+  // customisation
--- a/lib/deprecated.nix
+++ b/lib/deprecated.nix
@@ -1,12 +1,11 @@
-{ lib }:
-let
-    inherit (builtins) head tail isList isAttrs isInt attrNames;
+let lib = import ./default.nix;
+    inherit (builtins) isFunction head tail isList isAttrs isInt attrNames;

 in

-with lib.lists;
-with lib.attrsets;
-with lib.strings;
+with import ./lists.nix;
+with import ./attrsets.nix;
+with import ./strings.nix;

 rec {

@@ -17,23 +16,23 @@ rec {

  defaultMergeArg = x : y: if builtins.isAttrs y then
    y
-  else
+  else 
    (y x);
  defaultMerge = x: y: x // (defaultMergeArg x y);
-  foldArgs = merger: f: init: x:
-    let arg = (merger init (defaultMergeArg init x));
-        # now add the function with composed args already applied to the final attrs
-        base = (setAttrMerge "passthru" {} (f arg)
-                        ( z: z // rec {
-                            function = foldArgs merger f arg;
-                            args = (lib.attrByPath ["passthru" "args"] {} z) // x;
+  foldArgs = merger: f: init: x: 
+    let arg=(merger init (defaultMergeArg init x));
+      # now add the function with composed args already applied to the final attrs
+        base = (setAttrMerge "passthru" {} (f arg) 
+                        ( z : z // rec { 
+                          function = foldArgs merger f arg; 
+			  args = (lib.attrByPath ["passthru" "args"] {} z) // x;
                          } ));
-        withStdOverrides = base // {
-          override = base.passthru.function;
-        };
+	withStdOverrides = base // {
+	   override = base.passthru.function;
+	   } ;
        in
-          withStdOverrides;
-
+	withStdOverrides;
+    

  # predecessors: proposed replacement for applyAndFun (which has a bug cause it merges twice)
  # the naming "overridableDelayableArgs" tries to express that you can
@@ -50,35 +49,35 @@ rec {
  #
  # examples: see test cases "res" below;
  overridableDelayableArgs =
-          f:        # the function applied to the arguments
-          initial:  # you pass attrs, the functions below are passing a function taking the fix argument
+          f :        # the function applied to the arguments
+          initial :  # you pass attrs, the functions below are passing a function taking the fix argument
    let
-        takeFixed = if lib.isFunction initial then initial else (fixed : initial); # transform initial to an expression always taking the fixed argument
-        tidy = args:
+        takeFixed = if isFunction initial then initial else (fixed : initial); # transform initial to an expression always taking the fixed argument
+        tidy = args : 
            let # apply all functions given in "applyPreTidy" in sequence
-                applyPreTidyFun = fold ( n: a: x: n ( a x ) ) lib.id (maybeAttr "applyPreTidy" [] args);
+                applyPreTidyFun = fold ( n : a : x : n ( a x ) ) lib.id (maybeAttr "applyPreTidy" [] args);
            in removeAttrs (applyPreTidyFun args) ( ["applyPreTidy"] ++ (maybeAttr  "removeAttrs" [] args) ); # tidy up args before applying them
-        fun = n: x:
-            let newArgs = fixed:
-                    let args = takeFixed fixed;
-                        mergeFun = args.${n};
-                    in if isAttrs x then (mergeFun args x)
-                       else assert lib.isFunction x;
-                            mergeFun args (x ( args // { inherit fixed; }));
-            in overridableDelayableArgs f newArgs;
+        fun = n : x :
+             let newArgs = fixed :
+                     let args = takeFixed fixed; 
+                         mergeFun = args.${n};
+                     in if isAttrs x then (mergeFun args x)
+                        else assert isFunction x;
+                             mergeFun args (x ( args // { inherit fixed; }));
+             in overridableDelayableArgs f newArgs;
    in
    (f (tidy (lib.fix takeFixed))) // {
      merge   = fun "mergeFun";
      replace = fun "keepFun";
    };
-  defaultOverridableDelayableArgs = f:
+  defaultOverridableDelayableArgs = f : 
      let defaults = {
            mergeFun = mergeAttrByFunc; # default merge function. merge strategie (concatenate lists, strings) is given by mergeAttrBy
-            keepFun = a: b: { inherit (a) removeAttrs mergeFun keepFun mergeAttrBy; } // b; # even when using replace preserve these values
+            keepFun = a : b : { inherit (a) removeAttrs mergeFun keepFun mergeAttrBy; } // b; # even when using replace preserve these values
            applyPreTidy = []; # list of functions applied to args before args are tidied up (usage case : prepareDerivationArgs)
            mergeAttrBy = mergeAttrBy // {
-              applyPreTidy = a: b: a ++ b;
-              removeAttrs = a: b: a ++ b;
+              applyPreTidy = a : b : a ++ b;
+              removeAttrs = a : b: a ++ b;
            };
            removeAttrs = ["mergeFun" "keepFun" "mergeAttrBy" "removeAttrs" "fixed" ]; # before applying the arguments to the function make sure these names are gone
          };
@@ -87,7 +86,7 @@ rec {


  # rec { # an example of how composedArgsAndFun can be used
-  #  a  = composedArgsAndFun (x: x) { a = ["2"]; meta = { d = "bar";}; };
+  #  a  = composedArgsAndFun (x : x) { a = ["2"]; meta = { d = "bar";}; };
  #  # meta.d will be lost ! It's your task to preserve it (eg using a merge function)
  #  b  = a.passthru.function { a = [ "3" ]; meta = { d2 = "bar2";}; };
  #  # instead of passing/ overriding values you can use a merge function:
@@ -120,7 +119,7 @@ rec {
    else if val == true || val == false then false
    else null;

-
+    
  # Return true only if there is an attribute and it is true.
  checkFlag = attrSet: name:
        if name == "true" then true else
@@ -135,29 +134,29 @@ rec {
  ( attrByPath [name] (if checkFlag attrSet name then true else
        if argList == [] then null else
        let x = builtins.head argList; in
-                if (head x) == name then
+                if (head x) == name then 
                        (head (tail x))
-                else (getValue attrSet
+                else (getValue attrSet 
                        (tail argList) name)) attrSet );

-
+                        
  # Input : attrSet, [[name default] ...], [ [flagname reqs..] ... ]
  # Output : are reqs satisfied? It's asserted.
-  checkReqs = attrSet: argList: condList:
+  checkReqs = attrSet : argList : condList :
  (
-    fold lib.and true
-      (map (x: let name = (head x); in
-
-        ((checkFlag attrSet name) ->
+    fold lib.and true 
+      (map (x: let name = (head x) ; in
+        
+        ((checkFlag attrSet name) -> 
        (fold lib.and true
        (map (y: let val=(getValue attrSet argList y); in
-                (val!=null) && (val!=false))
-        (tail x))))) condList));
-
+                (val!=null) && (val!=false)) 
+        (tail x))))) condList)) ;
+        

  # This function has O(n^2) performance.
-  uniqList = { inputList, acc ? [] }:
-    let go = xs: acc:
+  uniqList = {inputList, acc ? []} :
+    let go = xs : acc :
             if xs == []
             then []
             else let x = head xs;
@@ -165,26 +164,26 @@ rec {
                  in y ++ go (tail xs) (y ++ acc);
    in go inputList acc;

-  uniqListExt = { inputList,
-                  outputList ? [],
-                  getter ? (x: x),
-                  compare ? (x: y: x==y) }:
+  uniqListExt = {inputList, outputList ? [],
+    getter ? (x : x), compare ? (x: y: x==y)}:
        if inputList == [] then outputList else
-        let x = head inputList;
-            isX = y: (compare (getter y) (getter x));
-            newOutputList = outputList ++
-                (if any isX outputList then [] else [x]);
-        in uniqListExt { outputList = newOutputList;
-                         inputList = (tail inputList);
-                         inherit getter compare;
-                       };
+        let x=head inputList; 
+        isX = y: (compare (getter y) (getter x));
+        newOutputList = outputList ++
+         (if any isX outputList then [] else [x]);
+        in uniqListExt {outputList=newOutputList; 
+                inputList = (tail inputList);
+                inherit getter compare;
+                };

+
+                
  condConcat = name: list: checker:
        if list == [] then name else
-        if checker (head list) then
-                condConcat
-                        (name + (head (tail list)))
-                        (tail (tail list))
+        if checker (head list) then 
+                condConcat 
+                        (name + (head (tail list))) 
+                        (tail (tail list)) 
                        checker
        else condConcat
                name (tail (tail list)) checker;
@@ -203,12 +202,12 @@ rec {
    in
      work startSet [] [];

-  innerModifySumArgs = f: x: a: b: if b == null then (f a b) // x else
+  innerModifySumArgs = f: x: a: b: if b == null then (f a b) // x else 
        innerModifySumArgs f x (a // b);
  modifySumArgs = f: x: innerModifySumArgs f x {};


-  innerClosePropagation = acc: xs:
+  innerClosePropagation = acc : xs :
    if xs == []
    then acc
    else let y  = head xs;
@@ -228,45 +227,45 @@ rec {
  closePropagation = list: (uniqList {inputList = (innerClosePropagation [] list);});

  # calls a function (f attr value ) for each record item. returns a list
-  mapAttrsFlatten = f: r: map (attr: f attr r.${attr}) (attrNames r);
+  mapAttrsFlatten = f : r : map (attr: f attr r.${attr}) (attrNames r);

  # attribute set containing one attribute
-  nvs = name: value: listToAttrs [ (nameValuePair name value) ];
+  nvs = name : value : listToAttrs [ (nameValuePair name value) ];
  # adds / replaces an attribute of an attribute set
-  setAttr = set: name: v: set // (nvs name v);
+  setAttr = set : name : v : set // (nvs name v);

  # setAttrMerge (similar to mergeAttrsWithFunc but only merges the values of a particular name)
-  # setAttrMerge "a" [] { a = [2];} (x: x ++ [3]) -> { a = [2 3]; }
-  # setAttrMerge "a" [] {         } (x: x ++ [3]) -> { a = [  3]; }
-  setAttrMerge = name: default: attrs: f:
+  # setAttrMerge "a" [] { a = [2];} (x : x ++ [3]) -> { a = [2 3]; } 
+  # setAttrMerge "a" [] {         } (x : x ++ [3]) -> { a = [  3]; }
+  setAttrMerge = name : default : attrs : f :
    setAttr attrs name (f (maybeAttr name default attrs));

-  # Using f = a: b = b the result is similar to //
+  # Using f = a : b = b the result is similar to //
  # merge attributes with custom function handling the case that the attribute
  # exists in both sets
-  mergeAttrsWithFunc = f: set1: set2:
-    fold (n: set: if set ? ${n}
+  mergeAttrsWithFunc = f : set1 : set2 :
+    fold (n: set : if set ? ${n}
                        then setAttr set n (f set.${n} set2.${n})
                        else set )
           (set2 // set1) (attrNames set2);

  # merging two attribute set concatenating the values of same attribute names
  # eg { a = 7; } {  a = [ 2 3 ]; } becomes { a = [ 7 2 3 ]; }
-  mergeAttrsConcatenateValues = mergeAttrsWithFunc ( a: b: (toList a) ++ (toList b) );
+  mergeAttrsConcatenateValues = mergeAttrsWithFunc ( a : b : (toList a) ++ (toList b) );

-  # merges attributes using //, if a name exists in both attributes
+  # merges attributes using //, if a name exisits in both attributes
  # an error will be triggered unless its listed in mergeLists
  # so you can mergeAttrsNoOverride { buildInputs = [a]; } { buildInputs = [a]; } {} to get
  # { buildInputs = [a b]; }
-  # merging buildPhase doesn't really make sense. The cases will be rare where appending /prefixing will fit your needs?
+  # merging buildPhase does'nt really make sense. The cases will be rare where appending /prefixing will fit your needs?
  # in these cases the first buildPhase will override the second one
  # ! deprecated, use mergeAttrByFunc instead
  mergeAttrsNoOverride = { mergeLists ? ["buildInputs" "propagatedBuildInputs"],
                           overrideSnd ? [ "buildPhase" ]
-                         }: attrs1: attrs2:
-    fold (n: set:
+                         } : attrs1 : attrs2 :
+    fold (n: set : 
        setAttr set n ( if set ? ${n}
-            then # merge
+            then # merge 
              if elem n mergeLists # attribute contains list, merge them by concatenating
                then attrs2.${n} ++ attrs1.${n}
              else if elem n overrideSnd
@@ -287,14 +286,14 @@ rec {
  # { mergeAttrsBy = [...]; buildInputs = [ a b c d ]; }
  # is used by prepareDerivationArgs, defaultOverridableDelayableArgs and can be used when composing using
  # foldArgs, composedArgsAndFun or applyAndFun. Example: composableDerivation in all-packages.nix
-  mergeAttrByFunc = x: y:
+  mergeAttrByFunc = x : y :
    let
-          mergeAttrBy2 = { mergeAttrBy = lib.mergeAttrs; }
+          mergeAttrBy2 = { mergeAttrBy=lib.mergeAttrs; }
                      // (maybeAttr "mergeAttrBy" {} x)
                      // (maybeAttr "mergeAttrBy" {} y); in
    fold lib.mergeAttrs {} [
      x y
-      (mapAttrs ( a: v: # merge special names using given functions
+      (mapAttrs ( a : v : # merge special names using given functions
          if x ? ${a}
             then if y ? ${a}
               then v x.${a} y.${a} # both have attr, use merge func
@@ -310,19 +309,58 @@ rec {
  mergeAttrsByFuncDefaults = foldl mergeAttrByFunc { inherit mergeAttrBy; };
  mergeAttrsByFuncDefaultsClean = list: removeAttrs (mergeAttrsByFuncDefaults list) ["mergeAttrBy"];

+  # merge attrs based on version key into mkDerivation args, see mergeAttrBy to learn about smart merge defaults
+  #
+  # This function is best explained by an example:
+  #
+  #     {version ? "2.x"} :
+  #
+  #     mkDerivation (mergeAttrsByVersion "package-name" version 
+  #       { # version specific settings
+  #         "git" = { src = ..; preConfigre = "autogen.sh"; buildInputs = [automake autoconf libtool];  };
+  #         "2.x" = { src = ..; };
+  #       }
+  #       {  // shared settings
+  #          buildInputs = [ common build inputs ];
+  #          meta = { .. }
+  #       }
+  #     )
+  #
+  # Please note that e.g. Eelco Dolstra usually prefers having one file for
+  # each version. On the other hand there are valuable additional design goals
+  #  - readability
+  #  - do it once only
+  #  - try to avoid duplication
+  #
+  # Marc Weber and Michael Raskin sometimes prefer keeping older
+  # versions around for testing and regression tests - as long as its cheap to
+  # do so.
+  #
+  # Very often it just happens that the "shared" code is the bigger part.
+  # Then using this function might be appropriate.
+  #
+  # Be aware that its easy to cause recompilations in all versions when using
+  # this function - also if derivations get too complex splitting into multiple
+  # files is the way to go.
+  #
+  # See misc.nix -> versionedDerivation
+  # discussion: nixpkgs: pull/310
+  mergeAttrsByVersion = name: version: attrsByVersion: base:
+    mergeAttrsByFuncDefaultsClean [ { name = "${name}-${version}"; } base (maybeAttr version (throw "bad version ${version} for ${name}") attrsByVersion)];
+
  # sane defaults (same name as attr name so that inherit can be used)
  mergeAttrBy = # { buildInputs = concatList; [...]; passthru = mergeAttr; [..]; }
-    listToAttrs (map (n: nameValuePair n lib.concat)
+    listToAttrs (map (n : nameValuePair n lib.concat)
      [ "nativeBuildInputs" "buildInputs" "propagatedBuildInputs" "configureFlags" "prePhases" "postAll" "patches" ])
-    // listToAttrs (map (n: nameValuePair n lib.mergeAttrs) [ "passthru" "meta" "cfg" "flags" ])
-    // listToAttrs (map (n: nameValuePair n (a: b: "${a}\n${b}") ) [ "preConfigure" "postInstall" ])
+    // listToAttrs (map (n : nameValuePair n lib.mergeAttrs) [ "passthru" "meta" "cfg" "flags" ])
+    // listToAttrs (map (n : nameValuePair n (a: b: "${a}\n${b}") ) [ "preConfigure" "postInstall" ])
  ;

  # prepareDerivationArgs tries to make writing configurable derivations easier
  # example:
  #  prepareDerivationArgs {
  #    mergeAttrBy = {
-  #       myScript = x: y: x ++ "\n" ++ y;
+  #       myScript = x : y : x ++ "\n" ++ y;
  #    };
  #    cfg = {
  #      readlineSupport = true;
@@ -354,10 +392,10 @@ rec {
  # TODO use args.mergeFun here as well?
  prepareDerivationArgs = args:
    let args2 = { cfg = {}; flags = {}; } // args;
-        flagName = name: "${name}Support";
-        cfgWithDefaults = (listToAttrs (map (n: nameValuePair (flagName n) false) (attrNames args2.flags)))
+        flagName = name : "${name}Support";
+        cfgWithDefaults = (listToAttrs (map (n : nameValuePair (flagName n) false) (attrNames args2.flags)))
                          // args2.cfg;
-        opts = attrValues (mapAttrs (a: v:
+        opts = attrValues (mapAttrs (a : v :
                let v2 = if v ? set || v ? unset then v else { set = v; };
                    n = if cfgWithDefaults.${flagName a} then "set" else "unset";
                    attr = maybeAttr n {} v2; in
@@ -374,7 +412,7 @@ rec {
      if isAttrs x then
          if x ? outPath then "derivation"
          else "attrs"
-      else if lib.isFunction x then "function"
+      else if isFunction x then "function"
      else if isList x then "list"
      else if x == true then "bool"
      else if x == false then "bool"
@@ -382,12 +420,4 @@ rec {
      else if isInt x then "int"
      else "string";

-  /* deprecated:
-
-     For historical reasons, imap has an index starting at 1.
-
-     But for consistency with the rest of the library we want an index
-     starting at zero.
-  */
-  imap = imap1;
 }
--- a/lib/fetchers.nix
+++ b/lib/fetchers.nix
@@ -1,5 +1,4 @@
-# snippets that can be shared by multiple fetchers (pkgs/build-support)
-{ lib }:
+# snippets that can be shared by mutliple fetchers (pkgs/build-support)
 {

  proxyImpureEnvVars = [
--- a/lib/filesystem.nix
+++ b/lib/filesystem.nix
@@ -1,45 +0,0 @@
-{ lib }:
-{ # haskellPathsInDir : Path -> Map String Path
-  # A map of all haskell packages defined in the given path,
-  # identified by having a cabal file with the same name as the
-  # directory itself.
-  haskellPathsInDir = root:
-    let # Files in the root
-        root-files = builtins.attrNames (builtins.readDir root);
-        # Files with their full paths
-        root-files-with-paths =
-          map (file:
-            { name = file; value = root + "/${file}"; }
-          ) root-files;
-        # Subdirectories of the root with a cabal file.
-        cabal-subdirs =
-          builtins.filter ({ name, value }:
-            builtins.pathExists (value + "/${name}.cabal")
-          ) root-files-with-paths;
-    in builtins.listToAttrs cabal-subdirs;
-  # locateDominatingFile :  RegExp
-  #                      -> Path
-  #                      -> Nullable { path : Path;
-  #                                    matches : [ MatchResults ];
-  #                                  }
-  # Find the first directory containing a file matching 'pattern'
-  # upward from a given 'file'.
-  # Returns 'null' if no directories contain a file matching 'pattern'.
-  locateDominatingFile = pattern: file:
-    let go = path:
-          let files = builtins.attrNames (builtins.readDir path);
-              matches = builtins.filter (match: match != null)
-                          (map (builtins.match pattern) files);
-          in
-            if builtins.length matches != 0
-              then { inherit path matches; }
-              else if path == /.
-                then null
-                else go (dirOf path);
-        parent = dirOf file;
-        isDir =
-          let base = baseNameOf file;
-              type = (builtins.readDir parent).${base} or null;
-          in file == /. || type == "directory";
-    in go (if isDir then file else parent);
-}
--- a/lib/fixed-points.nix
+++ b/lib/fixed-points.nix
@@ -1,79 +0,0 @@
-{ ... }:
-rec {
-  # Compute the fixed point of the given function `f`, which is usually an
-  # attribute set that expects its final, non-recursive representation as an
-  # argument:
-  #
-  #     f = self: { foo = "foo"; bar = "bar"; foobar = self.foo + self.bar; }
-  #
-  # Nix evaluates this recursion until all references to `self` have been
-  # resolved. At that point, the final result is returned and `f x = x` holds:
-  #
-  #     nix-repl> fix f
-  #     { bar = "bar"; foo = "foo"; foobar = "foobar"; }
-  #
-  #  Type: fix :: (a -> a) -> a
-  #
-  # See https://en.wikipedia.org/wiki/Fixed-point_combinator for further
-  # details.
-  fix = f: let x = f x; in x;
-
-  # A variant of `fix` that records the original recursive attribute set in the
-  # result. This is useful in combination with the `extends` function to
-  # implement deep overriding. See pkgs/development/haskell-modules/default.nix
-  # for a concrete example.
-  fix' = f: let x = f x // { __unfix__ = f; }; in x;
-
-  # Modify the contents of an explicitly recursive attribute set in a way that
-  # honors `self`-references. This is accomplished with a function
-  #
-  #     g = self: super: { foo = super.foo + " + "; }
-  #
-  # that has access to the unmodified input (`super`) as well as the final
-  # non-recursive representation of the attribute set (`self`). `extends`
-  # differs from the native `//` operator insofar as that it's applied *before*
-  # references to `self` are resolved:
-  #
-  #     nix-repl> fix (extends g f)
-  #     { bar = "bar"; foo = "foo + "; foobar = "foo + bar"; }
-  #
-  # The name of the function is inspired by object-oriented inheritance, i.e.
-  # think of it as an infix operator `g extends f` that mimics the syntax from
-  # Java. It may seem counter-intuitive to have the "base class" as the second
-  # argument, but it's nice this way if several uses of `extends` are cascaded.
-  extends = f: rattrs: self: let super = rattrs self; in super // f self super;
-
-  # Compose two extending functions of the type expected by 'extends'
-  # into one where changes made in the first are available in the
-  # 'super' of the second
-  composeExtensions =
-    f: g: self: super:
-      let fApplied = f self super;
-          super' = super // fApplied;
-      in fApplied // g self super';
-
-  # Create an overridable, recursive attribute set. For example:
-  #
-  #     nix-repl> obj = makeExtensible (self: { })
-  #
-  #     nix-repl> obj
-  #     { __unfix__ = «lambda»; extend = «lambda»; }
-  #
-  #     nix-repl> obj = obj.extend (self: super: { foo = "foo"; })
-  #
-  #     nix-repl> obj
-  #     { __unfix__ = «lambda»; extend = «lambda»; foo = "foo"; }
-  #
-  #     nix-repl> obj = obj.extend (self: super: { foo = super.foo + " + "; bar = "bar"; foobar = self.foo + self.bar; })
-  #
-  #     nix-repl> obj
-  #     { __unfix__ = «lambda»; bar = "bar"; extend = «lambda»; foo = "foo + "; foobar = "foo + bar"; }
-  makeExtensible = makeExtensibleWithCustomName "extend";
-
-  # Same as `makeExtensible` but the name of the extending attribute is
-  # customized.
-  makeExtensibleWithCustomName = extenderName: rattrs:
-    fix' rattrs // {
-      ${extenderName} = f: makeExtensibleWithCustomName extenderName (extends f rattrs);
-   };
-}
--- a/lib/generators.nix
+++ b/lib/generators.nix
@@ -7,15 +7,12 @@
 * Tests can be found in ./tests.nix
 * Documentation in the manual, #sec-generators
 */
-{ lib }:
-with (lib).trivial;
+with import ./trivial.nix;
 let
-  libStr = lib.strings;
-  libAttr = lib.attrsets;
+  libStr = import ./strings.nix;
+  libAttr = import ./attrsets.nix;

  flipMapAttrs = flip libAttr.mapAttrs;
-
-  inherit (lib) isFunction;
 in

 rec {
@@ -24,15 +21,11 @@ rec {
   * character sep. If sep appears in k, it is escaped.
   * Helper for synaxes with different separators.
   *
-   * mkValueString specifies how values should be formatted.
-   *
-   * mkKeyValueDefault {} ":" "f:oo" "bar"
+   * mkKeyValueDefault ":" "f:oo" "bar"
   * > "f\:oo:bar"
   */
-  mkKeyValueDefault = {
-    mkValueString ? toString
-  }: sep: k: v:
-    "${libStr.escape [sep] k}${sep}${mkValueString v}";
+  mkKeyValueDefault = sep: k: v:
+    "${libStr.escape [sep] k}${sep}${toString v}";


  /* Generate a key-value-style config file from an attrset.
@@ -40,7 +33,7 @@ rec {
   * mkKeyValue is the same as in toINI.
   */
  toKeyValue = {
-    mkKeyValue ? mkKeyValueDefault {} "="
+    mkKeyValue ? mkKeyValueDefault "="
  }: attrs:
    let mkLine = k: v: mkKeyValue k v + "\n";
    in libStr.concatStrings (libAttr.mapAttrsToList mkLine attrs);
@@ -70,7 +63,7 @@ rec {
    # apply transformations (e.g. escapes) to section names
    mkSectionName ? (name: libStr.escape [ "[" "]" ] name),
    # format a setting line from key and value
-    mkKeyValue    ? mkKeyValueDefault {} "="
+    mkKeyValue    ? mkKeyValueDefault "="
  }: attrsOfAttrs:
    let
        # map function to string for each key val
@@ -97,41 +90,4 @@ rec {
    * parsers as well.
    */
  toYAML = {}@args: toJSON args;
-
-  /* Pretty print a value, akin to `builtins.trace`.
-    * Should probably be a builtin as well.
-    */
-  toPretty = {
-    /* If this option is true, attrsets like { __pretty = fn; val = …; }
-       will use fn to convert val to a pretty printed representation.
-       (This means fn is type Val -> String.) */
-    allowPrettyValues ? false
-  }@args: v: with builtins;
-    if      isInt      v then toString v
-    else if isBool     v then (if v == true then "true" else "false")
-    else if isString   v then "\"" + v + "\""
-    else if null ==    v then "null"
-    else if isFunction v then
-      let fna = lib.functionArgs v;
-          showFnas = concatStringsSep "," (libAttr.mapAttrsToList
-                       (name: hasDefVal: if hasDefVal then "(${name})" else name)
-                       fna);
-      in if fna == {}    then "<λ>"
-                         else "<λ:{${showFnas}}>"
-    else if isList     v then "[ "
-        + libStr.concatMapStringsSep " " (toPretty args) v
-      + " ]"
-    else if isAttrs    v then
-      # apply pretty values if allowed
-      if attrNames v == [ "__pretty" "val" ] && allowPrettyValues
-         then v.__pretty v.val
-      # TODO: there is probably a better representation?
-      else if v ? type && v.type == "derivation" then "<δ>"
-      else "{ "
-          + libStr.concatStringsSep " " (libAttr.mapAttrsToList
-              (name: value:
-                "${toPretty args name} = ${toPretty args value};") v)
-        + " }"
-    else abort "toPretty: should never happen (v = ${v})";
-
 }
--- a/lib/licenses.nix
+++ b/lib/licenses.nix
@@ -1,8 +1,9 @@
-{ lib }:
 let

+  lib = import ./default.nix;
+
  spdx = lic: lic // {
-    url = "http://spdx.org/licenses/${lic.spdxId}.html";
+    url = "http://spdx.org/licenses/${lic.spdxId}";
  };

 in
@@ -15,12 +16,7 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {

  afl21 = spdx {
    spdxId = "AFL-2.1";
-    fullName = "Academic Free License v2.1";
-  };
-
-  afl3 = spdx {
-    spdxId = "AFL-3.0";
-    fullName = "Academic Free License v3.0";
+    fullName = "Academic Free License";
  };

  agpl3 = spdx {
@@ -49,11 +45,6 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    fullName = "Apple Public Source License 2.0";
  };

-  arphicpl = {
-    fullName = "Arphic Public License";
-    url = https://www.freedesktop.org/wiki/Arphic_Public_License/;
-  };
-
  artistic1 = spdx {
    spdxId = "Artistic-1.0";
    fullName = "Artistic License 1.0";
@@ -79,11 +70,6 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    fullName = ''Beerware License'';
  };

-  bsd0 = spdx {
-    spdxId = "0BSD";
-    fullName = "BSD Zero Clause License";
-  };
-
  bsd2 = spdx {
    spdxId = "BSD-2-Clause";
    fullName = ''BSD 2-clause "Simplified" License'';
@@ -99,11 +85,6 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    fullName = ''BSD 4-clause "Original" or "Old" License'';
  };

-  clArtistic = spdx {
-    spdxId = "ClArtistic";
-    fullName = "Clarified Artistic License";
-  };
-
  cc0 = spdx {
    spdxId = "CC0-1.0";
    fullName = "Creative Commons Zero v1.0 Universal";
@@ -189,12 +170,6 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    fullName = "DOC License";
  };

-  eapl = {
-    fullName = "EPSON AVASYS PUBLIC LICENSE";
-    url = http://avasys.jp/hp/menu000000700/hpg000000603.htm;
-    free = false;
-  };
-
  efl10 = spdx {
    spdxId = "EFL-1.0";
    fullName = "Eiffel Forum License v1.0";
@@ -210,11 +185,6 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    fullName = "Eclipse Public License 1.0";
  };

-  epl20 = spdx {
-    spdxId = "EPL-2.0";
-    fullName = "Eclipse Public License 2.0";
-  };
-
  epson = {
    fullName = "Seiko Epson Corporation Software License Agreement for Linux";
    url = https://download.ebz.epson.net/dsc/du/02/eula/global/LINUX_EN.html;
@@ -223,7 +193,7 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {

  eupl11 = spdx {
    spdxId = "EUPL-1.1";
-    fullName = "European Union Public License 1.1";
+    fullname = "European Union Public License 1.1";
  };

  fdl12 = spdx {
@@ -236,12 +206,6 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    fullName = "GNU Free Documentation License v1.3";
  };

-  ffsl = {
-    fullName = "Floodgap Free Software License";
-    url = http://www.floodgap.com/software/ffsl/license.html;
-    free = false;
-  };
-
  free = {
    fullName = "Unspecified free software license";
  };
@@ -302,11 +266,6 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    url = https://fedoraproject.org/wiki/Licensing/GPL_Classpath_Exception;
  };

-  hpnd = spdx {
-    spdxId = "HPND";
-    fullName = "Historic Permission Notice and Disclaimer";
-  };
-
  # Intel's license, seems free
  iasl = {
    fullName = "iASL";
@@ -318,16 +277,9 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    fullName = "Independent JPEG Group License";
  };

-  inria-compcert = {
-    fullName  = "INRIA Non-Commercial License Agreement for the CompCert verified compiler";
+  inria = {
+    fullName  = "INRIA Non-Commercial License Agreement";
    url       = "http://compcert.inria.fr/doc/LICENSE";
-    free      = false;
-  };
-
-  inria-icesl = {
-    fullName = "INRIA Non-Commercial License Agreement for IceSL";
-    url      = "http://shapeforge.loria.fr/icesl/EULA_IceSL_binary.pdf";
-    free     = false;
  };

  ipa = spdx {
@@ -405,11 +357,6 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    fullName = "Lucent Public License v1.02";
  };

-  miros = {
-    fullName = "MirOS License";
-    url = https://opensource.org/licenses/MirOS;
-  };
-
  # spdx.org does not (yet) differentiate between the X11 and Expat versions
  # for details see http://en.wikipedia.org/wiki/MIT_License#Various_versions
  mit = spdx {
@@ -451,12 +398,7 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    url = "https://raw.githubusercontent.com/raboof/notion/master/LICENSE";
    fullName = "Notion modified LGPL";
  };
-
-  nposl3 = spdx {
-    spdxId = "NPOSL-3.0";
-    fullName = "Non-Profit Open Software License 3.0";
-  };
-
+  
  ofl = spdx {
    spdxId = "OFL-1.1";
    fullName = "SIL Open Font License 1.1";
@@ -472,16 +414,6 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    fullName = "OpenSSL License";
  };

-  osl21 = spdx {
-    spdxId = "OSL-2.1";
-    fullName = "Open Software License 2.1";
-  };
-
-  osl3 = spdx {
-    spdxId = "OSL-3.0";
-    fullName = "Open Software License 3.0";
-  };
-
  php301 = spdx {
    spdxId = "PHP-3.01";
    fullName = "PHP License v3.01";
@@ -492,12 +424,6 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    fullName = "PostgreSQL License";
  };

-  postman = {
-    fullName = "Postman EULA";
-    url = https://www.getpostman.com/licenses/postman_base_app;
-    free = false;
-  };
-
  psfl = spdx {
    spdxId = "Python-2.0";
    fullName = "Python Software Foundation License version 2";
@@ -585,11 +511,6 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    fullName = "Vovida Software License v1.0";
  };

-  watcom = spdx {
-    spdxId = "Watcom-1.0";
-    fullName = "Sybase Open Watcom Public License 1.0";
-  };
-
  w3c = spdx {
    spdxId = "W3C";
    fullName = "W3C Software Notice and License";
@@ -605,23 +526,19 @@ lib.mapAttrs (n: v: v // { shortName = n; }) rec {
    fullName = "Do What The F*ck You Want To Public License";
  };

-  wxWindows = spdx {
-    spdxId = "WXwindows";
-    fullName = "wxWindows Library Licence, Version 3.1";
-  };
-
  zlib = spdx {
    spdxId = "Zlib";
    fullName = "zlib License";
  };

-  zpl20 = spdx {
+  zpt20 = spdx { # FIXME: why zpt* instead of zpl*
    spdxId = "ZPL-2.0";
    fullName = "Zope Public License 2.0";
  };

-  zpl21 = spdx {
+  zpt21 = spdx {
    spdxId = "ZPL-2.1";
    fullName = "Zope Public License 2.1";
  };
+
 }
--- a/lib/lists.nix
+++ b/lib/lists.nix
@@ -1,6 +1,6 @@
 # General list operations.
-{ lib }:
-with lib.trivial;
+
+with import ./trivial.nix;

 rec {

@@ -16,22 +16,17 @@ rec {
  */
  singleton = x: [x];

-  /* “right fold” a binary function `op' between successive elements of
-     `list' with `nul' as the starting value, i.e.,
-     `foldr op nul [x_1 x_2 ... x_n] == op x_1 (op x_2 ... (op x_n nul))'.
-     Type:
-       foldr :: (a -> b -> b) -> b -> [a] -> b
+  /* "Fold" a binary function `op' between successive elements of
+     `list' with `nul' as the starting value, i.e., `fold op nul [x_1
+     x_2 ... x_n] == op x_1 (op x_2 ... (op x_n nul))'.  (This is
+     Haskell's foldr).

     Example:
-       concat = foldr (a: b: a + b) "z"
+       concat = fold (a: b: a + b) "z"
       concat [ "a" "b" "c" ]
       => "abcz"
-       # different types
-       strange = foldr (int: str: toString (int + 1) + str) "a"
-       strange [ 1 2 3 4 ]
-       => "2345a"
  */
-  foldr = op: nul: list:
+  fold = op: nul: list:
    let
      len = length list;
      fold' = n:
@@ -40,25 +35,13 @@ rec {
        else op (elemAt list n) (fold' (n + 1));
    in fold' 0;

-  /* `fold' is an alias of `foldr' for historic reasons */
-  # FIXME(Profpatsch): deprecate?
-  fold = foldr;
-
-
-  /* “left fold”, like `foldr', but from the left:
-     `foldl op nul [x_1 x_2 ... x_n] == op (... (op (op nul x_1) x_2) ... x_n)`.
-
-     Type:
-       foldl :: (b -> a -> b) -> b -> [a] -> b
+  /* Left fold: `fold op nul [x_1 x_2 ... x_n] == op (... (op (op nul
+     x_1) x_2) ... x_n)'.

     Example:
       lconcat = foldl (a: b: a + b) "z"
       lconcat [ "a" "b" "c" ]
       => "zabc"
-       # different types
-       lstrange = foldl (str: int: str + toString (int + 1)) ""
-       strange [ 1 2 3 4 ]
-       => "a2345"
  */
  foldl = op: nul: list:
    let
@@ -69,7 +52,7 @@ rec {
        else op (foldl' (n - 1)) (elemAt list n);
    in foldl' (length list - 1);

-  /* Strict version of `foldl'.
+  /* Strict version of foldl.

     The difference is that evaluation is forced upon access. Usually used
     with small whole results (in contract with lazily-generated list or large
@@ -77,21 +60,15 @@ rec {
  */
  foldl' = builtins.foldl' or foldl;

-  /* Map with index starting from 0
+  /* Map with index
+
+     FIXME(zimbatm): why does this start to count at 1?

     Example:
-       imap0 (i: v: "${v}-${toString i}") ["a" "b"]
-       => [ "a-0" "b-1" ]
-  */
-  imap0 = f: list: genList (n: f n (elemAt list n)) (length list);
-
-  /* Map with index starting from 1
-
-     Example:
-       imap1 (i: v: "${v}-${toString i}") ["a" "b"]
+       imap (i: v: "${v}-${toString i}") ["a" "b"]
       => [ "a-1" "b-2" ]
  */
-  imap1 = f: list: genList (n: f (n + 1) (elemAt list n)) (length list);
+  imap = f: list: genList (n: f (n + 1) (elemAt list n)) (length list);

  /* Map and concatenate the result.

@@ -163,7 +140,7 @@ rec {
       any isString [ 1 { } ]
       => false
  */
-  any = builtins.any or (pred: foldr (x: y: if pred x then true else y) false);
+  any = builtins.any or (pred: fold (x: y: if pred x then true else y) false);

  /* Return true iff function `pred' returns true for all elements of
     `list'.
@@ -174,7 +151,7 @@ rec {
       all (x: x < 3) [ 1 2 3 ]
       => false
  */
-  all = builtins.all or (pred: foldr (x: y: if pred x then y else false) true);
+  all = builtins.all or (pred: fold (x: y: if pred x then y else false) true);

  /* Count how many times function `pred' returns true for the elements
     of `list'.
@@ -197,7 +174,7 @@ rec {
  */
  optional = cond: elem: if cond then [elem] else [];

-  /* Return a list or an empty list, depending on a boolean value.
+  /* Return a list or an empty list, dependening on a boolean value.

     Example:
       optionals true [ 2 3 ]
@@ -242,7 +219,7 @@ rec {
       => { right = [ 5 3 4 ]; wrong = [ 1 2 ]; }
  */
  partition = builtins.partition or (pred:
-    foldr (h: t:
+    fold (h: t:
      if pred h
      then { right = [h] ++ t.right; wrong = t.wrong; }
      else { right = t.right; wrong = [h] ++ t.wrong; }
@@ -385,30 +362,6 @@ rec {
      if len < 2 then list
      else (sort strictLess pivot.left) ++  [ first ] ++  (sort strictLess pivot.right));

-  /* Compare two lists element-by-element.
-
-     Example:
-       compareLists compare [] []
-       => 0
-       compareLists compare [] [ "a" ]
-       => -1
-       compareLists compare [ "a" ] []
-       => 1
-       compareLists compare [ "a" "b" ] [ "a" "c" ]
-       => 1
-  */
-  compareLists = cmp: a: b:
-    if a == []
-    then if b == []
-         then 0
-         else -1
-    else if b == []
-         then 1
-         else let rel = cmp (head a) (head b); in
-              if rel == 0
-              then compareLists cmp (tail a) (tail b)
-              else rel;
-
  /* Return the first (at most) N elements of a list.

     Example:
@@ -464,12 +417,8 @@ rec {
  init = list: assert list != []; take (length list - 1) list;


-  /* return the image of the cross product of some lists by a function
-
-    Example:
-      crossLists (x:y: "${toString x}${toString y}") [[1 2] [3 4]]
-      => [ "13" "14" "23" "24" ]
-  */
+  /* FIXME(zimbatm) Not used anywhere
+   */
  crossLists = f: foldl (fs: args: concatMap (f: map f args) fs) [f];


@@ -505,12 +454,4 @@ rec {
  */
  subtractLists = e: filter (x: !(elem x e));

-  /* Test if two lists have no common element.
-     It should be slightly more efficient than (intersectLists a b == [])
-  */
-  mutuallyExclusive = a: b:
-    (builtins.length a) == 0 ||
-    (!(builtins.elem (builtins.head a) b) &&
-     mutuallyExclusive (builtins.tail a) b);
-
 }
--- a/lib/maintainers.nix
+++ b/lib/maintainers.nix
@@ -0,0 +1,548 @@
+/* List of NixOS maintainers. The format is:
+
+    handle = "Real Name <address@example.org>";
+
+  where <handle> is preferred to be your GitHub username (so it's easy
+  to ping a package @<handle>), and <Real Name> is your real name, not
+  a pseudonym. Please keep the list alphabetically sorted. */
+{
+  a1russell = "Adam Russell <adamlr6+pub@gmail.com>";
+  aaronschif = "Aaron Schif <aaronschif@gmail.com>";
+  abaldeau = "Andreas Baldeau <andreas@baldeau.net>";
+  abbradar = "Nikolay Amiantov <ab@fmap.me>";
+  abigailbuccaneer = "Abigail Bunyan <abigailbuccaneer@gmail.com>";
+  aboseley = "Adam Boseley <adam.boseley@gmail.com>";
+  abuibrahim = "Ruslan Babayev <ruslan@babayev.com>";
+  acowley = "Anthony Cowley <acowley@gmail.com>";
+  adev = "Adrien Devresse <adev@adev.name>";
+  Adjective-Object = "Maxwell Huang-Hobbs <mhuan13@gmail.com>";
+  adnelson = "Allen Nelson <ithinkican@gmail.com>";
+  adolfogc = "Adolfo E. García Castro <adolfo.garcia.cr@gmail.com>";
+  aespinosa = "Allan Espinosa <allan.espinosa@outlook.com>";
+  aflatter = "Alexander Flatter <flatter@fastmail.fm>";
+  afldcr   = "James Alexander Feldman-Crough <alex@fldcr.com>";
+  aforemny = "Alexander Foremny <alexanderforemny@googlemail.com>";
+  afranchuk = "Alex Franchuk <alex.franchuk@gmail.com>";
+  aherrmann = "Andreas Herrmann <andreash87@gmx.ch>";
+  ak = "Alexander Kjeldaas <ak@formalprivacy.com>";
+  akaWolf = "Artjom Vejsel <akawolf0@gmail.com>";
+  akc = "Anders Claesson <akc@akc.is>";
+  algorith = "Dries Van Daele <dries_van_daele@telenet.be>";
+  alibabzo = "Alistair Bill <alistair.bill@gmail.com>";
+  all = "Nix Committers <nix-commits@lists.science.uu.nl>";
+  ambrop72 = "Ambroz Bizjak <ambrop7@gmail.com>";
+  amiddelk = "Arie Middelkoop <amiddelk@gmail.com>";
+  amiloradovsky = "Andrew Miloradovsky <miloradovsky@gmail.com>";
+  amorsillo = "Andrew Morsillo <andrew.morsillo@gmail.com>";
+  AndersonTorres = "Anderson Torres <torres.anderson.85@gmail.com>";
+  anderspapitto = "Anders Papitto <anderspapitto@gmail.com>";
+  andres = "Andres Loeh <ksnixos@andres-loeh.de>";
+  andrewrk = "Andrew Kelley <superjoe30@gmail.com>";
+  andsild = "Anders Sildnes <andsild@gmail.com>";
+  aneeshusa = "Aneesh Agrawal <aneeshusa@gmail.com>";
+  antono = "Antono Vasiljev <self@antono.info>";
+  apeyroux = "Alexandre Peyroux <alex@px.io>";
+  ardumont = "Antoine R. Dumont <eniotna.t@gmail.com>";
+  aristid = "Aristid Breitkreuz <aristidb@gmail.com>";
+  arobyn = "Alexei Robyn <shados@shados.net>";
+  artuuge = "Artur E. Ruuge <artuuge@gmail.com>";
+  ashalkhakov = "Artyom Shalkhakov <artyom.shalkhakov@gmail.com>";
+  aske = "Kirill Boltaev <aske@fmap.me>";
+  asppsa = "Alastair Pharo <asppsa@gmail.com>";
+  astsmtl = "Alexander Tsamutali <astsmtl@yandex.ru>";
+  asymmetric = "Lorenzo Manacorda <lorenzo@mailbox.org>";
+  aszlig = "aszlig <aszlig@redmoonstudios.org>";
+  auntie = "Jonathan Glines <auntieNeo@gmail.com>";
+  avnik = "Alexander V. Nikolaev <avn@avnik.info>";
+  aycanirican = "Aycan iRiCAN <iricanaycan@gmail.com>";
+  bachp = "Pascal Bach <pascal.bach@nextrem.ch>";
+  badi = "Badi' Abdul-Wahid <abdulwahidc@gmail.com>";
+  balajisivaraman = "Balaji Sivaraman<sivaraman.balaji@gmail.com>";
+  Baughn = "Svein Ove Aas <sveina@gmail.com>";
+  bbenoist = "Baptist BENOIST <return_0@live.com>";
+  bcarrell = "Brandon Carrell <brandoncarrell@gmail.com>";
+  bcdarwin = "Ben Darwin <bcdarwin@gmail.com>";
+  bdimcheff = "Brandon Dimcheff <brandon@dimcheff.com>";
+  benley = "Benjamin Staffin <benley@gmail.com>";
+  bennofs = "Benno Fünfstück <benno.fuenfstueck@gmail.com>";
+  benwbooth = "Ben Booth <benwbooth@gmail.com>";
+  berdario = "Dario Bertini <berdario@gmail.com>";
+  bergey = "Daniel Bergey <bergey@teallabs.org>";
+  bjg = "Brian Gough <bjg@gnu.org>";
+  bjornfor = "Bjørn Forsman <bjorn.forsman@gmail.com>";
+  bluescreen303 = "Mathijs Kwik <mathijs@bluescreen303.nl>";
+  bobvanderlinden = "Bob van der Linden <bobvanderlinden@gmail.com>";
+  bodil = "Bodil Stokke <nix@bodil.org>";
+  boothead = "Ben Ford <ben@perurbis.com>";
+  bosu = "Boris Sukholitko <boriss@gmail.com>";
+  bradediger = "Brad Ediger <brad@bradediger.com>";
+  bramd = "Bram Duvigneau <bram@bramd.nl>";
+  bstrik = "Berno Strik <dutchman55@gmx.com>";
+  bzizou = "Bruno Bzeznik <Bruno@bzizou.net>";
+  c0dehero = "CodeHero <codehero@nerdpol.ch>";
+  calrama = "Moritz Maxeiner <moritz@ucworks.org>";
+  campadrenalin = "Philip Horger <campadrenalin@gmail.com>";
+  canndrew = "Andrew Cann <shum@canndrew.org>";
+  carlsverre = "Carl Sverre <accounts@carlsverre.com>";
+  cdepillabout = "Dennis Gosnell <cdep.illabout@gmail.com>";
+  cfouche = "Chaddaï Fouché <chaddai.fouche@gmail.com>";
+  chaoflow = "Florian Friesdorf <flo@chaoflow.net>";
+  chattered = "Phil Scott <me@philscotted.com>";
+  changlinli = "Changlin Li <mail@changlinli.com>";
+  choochootrain = "Hurshal Patel <hurshal@imap.cc>";
+  chris-martin = "Chris Martin <ch.martin@gmail.com>";
+  chrisjefferson = "Christopher Jefferson <chris@bubblescope.net>";
+  christopherpoole = "Christopher Mark Poole <mail@christopherpoole.net>";
+  ckampka = "Christian Kampka <christian@kampka.net>";
+  cko = "Christine Koppelt <christine.koppelt@gmail.com>";
+  cleverca22 = "Michael Bishop <cleverca22@gmail.com>";
+  cmcdragonkai = "Roger Qiu <roger.qiu@matrix.ai>";
+  cmfwyp = "cmfwyp <cmfwyp@riseup.net>";
+  coconnor = "Corey O'Connor <coreyoconnor@gmail.com>";
+  codsl = "codsl <codsl@riseup.net>";
+  codyopel = "Cody Opel <codyopel@gmail.com>";
+  colemickens = "Cole Mickens <cole.mickens@gmail.com>";
+  copumpkin = "Dan Peebles <pumpkingod@gmail.com>";
+  corngood = "David McFarland <corngood@gmail.com>";
+  coroa = "Jonas Hörsch <jonas@chaoflow.net>";
+  couchemar = "Andrey Pavlov <couchemar@yandex.ru>";
+  cpages = "Carles Pagès <page@ruiec.cat>";
+  cransom = "Casey Ransom <cransom@hubns.net>";
+  cryptix = "Henry Bubert <cryptix@riseup.net>";
+  CrystalGamma = "Jona Stubbe <nixos@crystalgamma.de>";
+  cstrahan = "Charles Strahan <charles@cstrahan.com>";
+  cwoac = "Oliver Matthews <oliver@codersoffortune.net>";
+  DamienCassou = "Damien Cassou <damien@cassou.me>";
+  danbst = "Danylo Hlynskyi <abcz2.uprola@gmail.com>";
+  dancek = "Hannu Hartikainen <hannu.hartikainen@gmail.com>";
+  danielfullmer = "Daniel Fullmer <danielrf12@gmail.com>";
+  dasuxullebt = "Christoph-Simon Senjak <christoph.senjak@googlemail.com>";
+  davidak = "David Kleuker <post@davidak.de>";
+  davidrusu = "David Rusu <davidrusu.me@gmail.com>";
+  davorb = "Davor Babic <davor@davor.se>";
+  dbohdan = "Danyil Bohdan <danyil.bohdan@gmail.com>";
+  dbrock = "Daniel Brockman <daniel@brockman.se>";
+  deepfire = "Kosyrev Serge <_deepfire@feelingofgreen.ru>";
+  demin-dmitriy = "Dmitriy Demin <demindf@gmail.com>";
+  DerGuteMoritz = "Moritz Heidkamp <moritz@twoticketsplease.de>";
+  DerTim1 = "Tim Digel <tim.digel@active-group.de>";
+  desiderius = "Didier J. Devroye <didier@devroye.name>";
+  devhell = "devhell <\"^\"@regexmail.net>";
+  dezgeg = "Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>";
+  dfoxfranke = "Daniel Fox Franke <dfoxfranke@gmail.com>";
+  dgonyeo = "Derek Gonyeo <derek@gonyeo.com>";
+  dipinhora = "Dipin Hora <dipinhora+github@gmail.com>";
+  dmalikov = "Dmitry Malikov <malikov.d.y@gmail.com>";
+  dochang = "Desmond O. Chang <dochang@gmail.com>";
+  domenkozar = "Domen Kozar <domen@dev.si>";
+  doublec = "Chris Double <chris.double@double.co.nz>";
+  dpaetzel = "David Pätzel <david.a.paetzel@gmail.com>";
+  drets = "Dmytro Rets <dmitryrets@gmail.com>";
+  drewkett = "Andrew Burkett <burkett.andrew@gmail.com>";
+  dtzWill = "Will Dietz <nix@wdtz.org>";
+  e-user = "Alexander Kahl <nixos@sodosopa.io>";
+  ebzzry = "Rommel Martinez <ebzzry@gmail.com>";
+  edanaher = "Evan Danaher <nixos@edanaher.net>";
+  ederoyd46 = "Matthew Brown <matt@ederoyd.co.uk>";
+  eduarrrd = "Eduard Bachmakov <e.bachmakov@gmail.com>";
+  edwtjo = "Edward Tjörnhammar <ed@cflags.cc>";
+  eelco = "Eelco Dolstra <eelco.dolstra@logicblox.com>";
+  ehegnes = "Eric Hegnes <eric.hegnes@gmail.com>";
+  ehmry = "Emery Hemingway <emery@vfemail.net>";
+  eikek = "Eike Kettner <eike.kettner@posteo.de>";
+  elasticdog = "Aaron Bull Schaefer <aaron@elasticdog.com>";
+  eleanor = "Dejan Lukan <dejan@proteansec.com>";
+  elitak = "Eric Litak <elitak@gmail.com>";
+  ellis = "Ellis Whitehead <nixos@ellisw.net>";
+  epitrochoid = "Mabry Cervin <mpcervin@uncg.edu>";
+  ericbmerritt = "Eric Merritt <eric@afiniate.com>";
+  ericsagnes = "Eric Sagnes <eric.sagnes@gmail.com>";
+  erikryb = "Erik Rybakken <erik.rybakken@math.ntnu.no>";
+  ertes = "Ertugrul Söylemez <esz@posteo.de>";
+  ethercrow = "Dmitry Ivanov <ethercrow@gmail.com>";
+  exi = "Reno Reckling <nixos@reckling.org>";
+  exlevan = "Alexey Levan <exlevan@gmail.com>";
+  expipiplus1 = "Joe Hermaszewski <nix@monoid.al>";
+  fadenb = "Tristan Helmich <tristan.helmich+nixos@gmail.com>";
+  falsifian = "James Cook <james.cook@utoronto.ca>";
+  flosse = "Markus Kohlhase <mail@markus-kohlhase.de>";
+  fluffynukeit = "Daniel Austin <dan@fluffynukeit.com>";
+  fmthoma = "Franz Thoma <f.m.thoma@googlemail.com>";
+  forkk = "Andrew Okin <forkk@forkk.net>";
+  fornever = "Friedrich von Never <friedrich@fornever.me>";
+  fpletz = "Franz Pletz <fpletz@fnordicwalking.de>";
+  fps = "Florian Paul Schmidt <mista.tapas@gmx.net>";
+  fridh = "Frederik Rietdijk <fridh@fridh.nl>";
+  frlan = "Frank Lanitz <frank@frank.uvena.de>";
+  fro_ozen = "fro_ozen <fro_ozen@gmx.de>";
+  ftrvxmtrx = "Siarhei Zirukin <ftrvxmtrx@gmail.com>";
+  funfunctor = "Edward O'Callaghan <eocallaghan@alterapraxis.com>";
+  fuuzetsu = "Mateusz Kowalczyk <fuuzetsu@fuuzetsu.co.uk>";
+  fxfactorial = "Edgar Aroutiounian <edgar.factorial@gmail.com>";
+  gal_bolle = "Florent Becker <florent.becker@ens-lyon.org>";
+  garbas = "Rok Garbas <rok@garbas.si>";
+  garrison = "Jim Garrison <jim@garrison.cc>";
+  gavin = "Gavin Rogers <gavin@praxeology.co.uk>";
+  gebner = "Gabriel Ebner <gebner@gebner.org>";
+  gilligan = "Tobias Pflug <tobias.pflug@gmail.com>";
+  giogadi = "Luis G. Torres <lgtorres42@gmail.com>";
+  gleber = "Gleb Peregud <gleber.p@gmail.com>";
+  globin = "Robin Gloster <mail@glob.in>";
+  gnidorah = "Alex Ivanov <yourbestfriend@opmbx.org>";
+  goibhniu = "Cillian de Róiste <cillian.deroiste@gmail.com>";
+  Gonzih = "Max Gonzih <gonzih@gmail.com>";
+  goodrone = "Andrew Trachenko <goodrone@gmail.com>";
+  gpyh = "Yacine Hmito <yacine.hmito@gmail.com>";
+  grahamc = "Graham Christensen <graham@grahamc.com>";
+  gridaphobe = "Eric Seidel <eric@seidel.io>";
+  guibert = "David Guibert <david.guibert@gmail.com>";
+  guillaumekoenig = "Guillaume Koenig <guillaume.edward.koenig@gmail.com>";
+  guyonvarch = "Joris Guyonvarch <joris@guyonvarch.me>";
+  hakuch = "Jesse Haber-Kucharsky <hakuch@gmail.com>";
+  havvy = "Ryan Scheel <ryan.havvy@gmail.com>";
+  hbunke = "Hendrik Bunke <bunke.hendrik@gmail.com>";
+  hce = "Hans-Christian Esperer <hc@hcesperer.org>";
+  henrytill = "Henry Till <henrytill@gmail.com>";
+  hinton = "Tom Hinton <t@larkery.com>";
+  hrdinka = "Christoph Hrdinka <c.nix@hrdinka.at>";
+  iand675 = "Ian Duncan <ian@iankduncan.com>";
+  ianwookim = "Ian-Woo Kim <ianwookim@gmail.com>";
+  igsha = "Igor Sharonov <igor.sharonov@gmail.com>";
+  ikervagyok = "Balázs Lengyel <ikervagyok@gmail.com>";
+  ivan-tkatchev = "Ivan Tkatchev <tkatchev@gmail.com>";
+  j-keck = "Jürgen Keck <jhyphenkeck@gmail.com>";
+  jagajaga = "Arseniy Seroka <ars.seroka@gmail.com>";
+  javaguirre = "Javier Aguirre <contacto@javaguirre.net>";
+  jb55 = "William Casarin <bill@casarin.me>";
+  jbedo = "Justin Bedő <cu@cua0.org>";
+  jcumming = "Jack Cummings <jack@mudshark.org>";
+  jdagilliland = "Jason Gilliland <jdagilliland@gmail.com>";
+  jefdaj = "Jeffrey David Johnson <jefdaj@gmail.com>";
+  jerith666 = "Matt McHenry <github@matt.mchenryfamily.org>";
+  jfb = "James Felix Black <james@yamtime.com>";
+  jgeerds = "Jascha Geerds <jascha@jgeerds.name>";
+  jgertm = "Tim Jaeger <jger.tm@gmail.com>";
+  jgillich = "Jakob Gillich <jakob@gillich.me>";
+  jirkamarsik = "Jirka Marsik <jiri.marsik89@gmail.com>";
+  joachifm = "Joachim Fasting <joachifm@fastmail.fm>";
+  joamaki = "Jussi Maki <joamaki@gmail.com>";
+  joelmo = "Joel Moberg <joel.moberg@gmail.com>";
+  joelteon = "Joel Taylor <me@joelt.io>";
+  johbo = "Johannes Bornhold <johannes@bornhold.name>";
+  joko = "Ioannis Koutras <ioannis.koutras@gmail.com>";
+  jonafato = "Jon Banafato <jon@jonafato.com>";
+  jpbernardy = "Jean-Philippe Bernardy <jeanphilippe.bernardy@gmail.com>";
+  jpierre03 = "Jean-Pierre PRUNARET <nix@prunetwork.fr>";
+  jraygauthier = "Raymond Gauthier <jraygauthier@gmail.com>";
+  juliendehos = "Julien Dehos <dehos@lisic.univ-littoral.fr>";
+  jwiegley = "John Wiegley <johnw@newartisans.com>";
+  jwilberding = "Jordan Wilberding <jwilberding@afiniate.com>";
+  jzellner = "Jeff Zellner <jeffz@eml.cc>";
+  kaiha = "Kai Harries <kai.harries@gmail.com>";
+  kamilchm = "Kamil Chmielewski <kamil.chm@gmail.com>";
+  kampfschlaefer = "Arnold Krille <arnold@arnoldarts.de>";
+  kevincox = "Kevin Cox <kevincox@kevincox.ca>";
+  khumba = "Bryan Gardiner <bog@khumba.net>";
+  KibaFox = "Kiba Fox <kiba.fox@foxypossibilities.com>";
+  kierdavis = "Kier Davis <kierdavis@gmail.com>";
+  kkallio = "Karn Kallio <tierpluspluslists@gmail.com>";
+  knedlsepp = "Josef Kemetmüller <josef.kemetmueller@gmail.com>";
+  koral = "Koral <koral@mailoo.org>";
+  kovirobi = "Kovacsics Robert <kovirobi@gmail.com>";
+  kragniz = "Louis Taylor <louis@kragniz.eu>";
+  kristoff3r = "Kristoffer Søholm <k.soeholm@gmail.com>";
+  ktosiek = "Tomasz Kontusz <tomasz.kontusz@gmail.com>";
+  lassulus = "Lassulus <lassulus@gmail.com>";
+  layus = "Guillaume Maudoux <layus.on@gmail.com>";
+  ldesgoui = "Lucas Desgouilles <ldesgoui@gmail.com>";
+  league = "Christopher League <league@contrapunctus.net>";
+  lebastr = "Alexander Lebedev <lebastr@gmail.com>";
+  leemachin = "Lee Machin <me@mrl.ee>";
+  leenaars = "Michiel Leenaars <ml.software@leenaa.rs>";
+  leonardoce = "Leonardo Cecchi <leonardo.cecchi@gmail.com>";
+  lethalman = "Luca Bruno <lucabru@src.gnome.org>";
+  lewo = "Antoine Eiche <lewo@abesis.fr>";
+  lheckemann = "Linus Heckemann <git@sphalerite.org>";
+  lhvwb = "Nathaniel Baxter <nathaniel.baxter@gmail.com>";
+  lihop = "Leroy Hopson <nixos@leroy.geek.nz>";
+  linquize = "Linquize <linquize@yahoo.com.hk>";
+  linus = "Linus Arver <linusarver@gmail.com>";
+  lnl7 = "Daiderd Jordan <daiderd@gmail.com>";
+  loskutov = "Ignat Loskutov <ignat.loskutov@gmail.com>";
+  lovek323 = "Jason O'Conal <jason@oconal.id.au>";
+  lowfatcomputing = "Andreas Wagner <andreas.wagner@lowfatcomputing.org>";
+  lsix = "Lancelot SIX <lsix@lancelotsix.com>";
+  lucas8 = "Luc Chabassier <luc.linux@mailoo.org>";
+  ludo = "Ludovic Courtès <ludo@gnu.org>";
+  luispedro = "Luis Pedro Coelho <luis@luispedro.org>";
+  lukego = "Luke Gorrie <luke@snabb.co>";
+  lw = "Sergey Sofeychuk <lw@fmap.me>";
+  ma27 = "Maximilian Bosch <maximilian@mbosch.me>";
+  madjar = "Georges Dubus <georges.dubus@compiletoi.net>";
+  magnetophon = "Bart Brouns <bart@magnetophon.nl>";
+  mahe = "Matthias Herrmann <matthias.mh.herrmann@gmail.com>";
+  makefu = "Felix Richter <makefu@syntax-fehler.de>";
+  malyn = "Michael Alyn Miller <malyn@strangeGizmo.com>";
+  manveru = "Michael Fellinger <m.fellinger@gmail.com>";
+  marcweber = "Marc Weber <marco-oweber@gmx.de>";
+  markus1189 = "Markus Hauck <markus1189@gmail.com>";
+  markWot = "Markus Wotringer <markus@wotringer.de>";
+  martijnvermaat = "Martijn Vermaat <martijn@vermaat.name>";
+  martingms = "Martin Gammelsæter <martin@mg.am>";
+  matejc = "Matej Cotman <cotman.matej@gmail.com>";
+  mathnerd314 = "Mathnerd314 <mathnerd314.gph+hs@gmail.com>";
+  matthewbauer = "Matthew Bauer <mjbauer95@gmail.com>";
+  matthiasbeyer = "Matthias Beyer <mail@beyermatthias.de>";
+  maurer = "Matthew Maurer <matthew.r.maurer+nix@gmail.com>";
+  mbakke = "Marius Bakke <mbakke@fastmail.com>";
+  mbbx6spp = "Susan Potter <me@susanpotter.net>";
+  mbe = "Brandon Edens <brandonedens@gmail.com>";
+  mboes = "Mathieu Boespflug <mboes@tweag.net>";
+  mbrgm = "Marius Bergmann <marius@yeai.de>";
+  mcmtroffaes = "Matthias C. M. Troffaes <matthias.troffaes@gmail.com>";
+  mdaiter = "Matthew S. Daiter <mdaiter8121@gmail.com>";
+  meditans = "Carlo Nucera <meditans@gmail.com>";
+  meisternu = "Matt Miemiec <meister@krutt.org>";
+  metabar = "Celine Mercier <softs@metabarcoding.org>";
+  mguentner = "Maximilian Güntner <code@klandest.in>";
+  mic92 = "Jörg Thalheim <joerg@thalheim.io>";
+  michaelpj = "Michael Peyton Jones <michaelpj@gmail.com>";
+  michalrus = "Michal Rus <m@michalrus.com>";
+  michelk = "Michel Kuhlmann <michel@kuhlmanns.info>";
+  mikefaille = "Michaël Faille <michael@faille.io>";
+  mimadrid = "Miguel Madrid <mimadrid@ucm.es>";
+  mingchuan = "Ming Chuan <ming@culpring.com>";
+  mirdhyn = "Merlin Gaillard <mirdhyn@gmail.com>";
+  mirrexagon = "Andrew Abbott <mirrexagon@mirrexagon.com>";
+  mjanczyk = "Marcin Janczyk <m@dragonvr.pl>";
+  mlieberman85 = "Michael Lieberman <mlieberman85@gmail.com>";
+  modulistic = "Pablo Costa <modulistic@gmail.com>";
+  mog = "Matthew O'Gorman <mog-lists@rldn.net>";
+  montag451 = "montag451 <montag451@laposte.net>";
+  moosingin3space = "Nathan Moos <moosingin3space@gmail.com>";
+  moretea = "Maarten Hoogendoorn <maarten@moretea.nl>";
+  mornfall = "Petr Ročkai <me@mornfall.net>";
+  MostAwesomeDude = "Corbin Simpson <cds@corbinsimpson.com>";
+  mounium = "Katona László <muoniurn@gmail.com>";
+  MP2E = "Cray Elliott <MP2E@archlinux.us>";
+  mpscholten = "Marc Scholten <marc@mpscholten.de>";
+  mpsyco = "Francis St-Amour <fr.st-amour@gmail.com>";
+  msackman = "Matthew Sackman <matthew@wellquite.org>";
+  mschristiansen = "Mikkel Christiansen <mikkel@rheosystems.com>";
+  msteen = "Matthijs Steen <emailmatthijs@gmail.com>";
+  mtreskin = "Max Treskin <zerthurd@gmail.com>";
+  mudri = "James Wood <lamudri@gmail.com>";
+  muflax = "Stefan Dorn <mail@muflax.com>";
+  myrl = "Myrl Hex <myrl.0xf@gmail.com>";
+  namore = "Roman Naumann <namor@hemio.de>";
+  nand0p = "Fernando Jose Pando <nando@hex7.com>";
+  Nate-Devv = "Nathan Moore <natedevv@gmail.com>";
+  nathan-gs = "Nathan Bijnens <nathan@nathan.gs>";
+  nckx = "Tobias Geerinckx-Rice <tobias.geerinckx.rice@gmail.com>";
+  ndowens = "Nathan Owens <ndowens04@gmail.com>";
+  nequissimus = "Tim Steinbach <tim@nequissimus.com>";
+  nfjinjing = "Jinjing Wang <nfjinjing@gmail.com>";
+  nhooyr = "Anmol Sethi <anmol@aubble.com>";
+  nickhu = "Nick Hu <me@nickhu.co.uk>";
+  nicknovitski = "Nick Novitski <nixpkgs@nicknovitski.com>";
+  nico202 = "Nicolò Balzarotti <anothersms@gmail.com>";
+  NikolaMandic = "Ratko Mladic <nikola@mandic.email>";
+  nixy = "Andrew R. M. <andrewmiller237@gmail.com>";
+  nocoolnametom = "Tom Doggett <nocoolnametom@gmail.com>";
+  notthemessiah = "Brian Cohen <brian.cohen.88@gmail.com>";
+  np = "Nicolas Pouillard <np.nix@nicolaspouillard.fr>";
+  nslqqq = "Nikita Mikhailov <nslqqq@gmail.com>";
+  obadz = "obadz <obadz-nixos@obadz.com>";
+  ocharles = "Oliver Charles <ollie@ocharles.org.uk>";
+  odi = "Oliver Dunkl <oliver.dunkl@gmail.com>";
+  offline = "Jaka Hudoklin <jakahudoklin@gmail.com>";
+  oida = "oida <oida@posteo.de>";
+  okasu = "Okasu <oka.sux@gmail.com>";
+  olcai = "Erik Timan <dev@timan.info>";
+  olejorgenb = "Ole Jørgen Brønner <olejorgenb@yahoo.no>";
+  orbekk = "KJ Ørbekk <kjetil.orbekk@gmail.com>";
+  orbitz = "Malcolm Matalka <mmatalka@gmail.com>";
+  orivej = "Orivej Desh <orivej@gmx.fr>";
+  osener = "Ozan Sener <ozan@ozansener.com>";
+  otwieracz = "Slawomir Gonet <slawek@otwiera.cz>";
+  oxij = "Jan Malakhovski <oxij@oxij.org>";
+  paholg = "Paho Lurie-Gregg <paho@paholg.com>";
+  pakhfn = "Fedor Pakhomov <pakhfn@gmail.com>";
+  palo = "Ingolf Wanger <palipalo9@googlemail.com>";
+  paperdigits = "Mica Semrick <mica@silentumbrella.com>";
+  pashev = "Igor Pashev <pashev.igor@gmail.com>";
+  pawelpacana = "Paweł Pacana <pawel.pacana@gmail.com>";
+  periklis = "theopompos@gmail.com";
+  pesterhazy = "Paulus Esterhazy <pesterhazy@gmail.com>";
+  peterhoeg = "Peter Hoeg <peter@hoeg.com>";
+  peti = "Peter Simons <simons@cryp.to>";
+  philandstuff = "Philip Potter <philip.g.potter@gmail.com>";
+  phile314 = "Philipp Hausmann <nix@314.ch>";
+  Phlogistique = "Noé Rubinstein <noe.rubinstein@gmail.com>";
+  phreedom = "Evgeny Egorochkin <phreedom@yandex.ru>";
+  phunehehe = "Hoang Xuan Phu <phunehehe@gmail.com>";
+  pierron = "Nicolas B. Pierron <nixos@nbp.name>";
+  piotr = "Piotr Pietraszkiewicz <ppietrasa@gmail.com>";
+  pjbarnoy = "Perry Barnoy <pjbarnoy@gmail.com>";
+  pjones = "Peter Jones <pjones@devalot.com>";
+  pkmx = "Chih-Mao Chen <pkmx.tw@gmail.com>";
+  plcplc = "Philip Lykke Carlsen <plcplc@gmail.com>";
+  pmahoney = "Patrick Mahoney <pat@polycrystal.org>";
+  pmiddend = "Philipp Middendorf <pmidden@secure.mailbox.org>";
+  polyrod = "Maurizio Di Pietro <dc1mdp@gmail.com>";
+  pradeepchhetri = "Pradeep Chhetri <pradeep.chhetri89@gmail.com>";
+  prikhi = "Pavan Rikhi <pavan.rikhi@gmail.com>";
+  primeos = "Michael Weiss <dev.primeos@gmail.com>";
+  profpatsch = "Profpatsch <mail@profpatsch.de>";
+  proglodyte = "Proglodyte <proglodyte23@gmail.com>";
+  pshendry = "Paul Hendry <paul@pshendry.com>";
+  psibi = "Sibi <sibi@psibi.in>";
+  pstn = "Philipp Steinpaß <philipp@xndr.de>";
+  pSub = "Pascal Wittmann <mail@pascal-wittmann.de>";
+  puffnfresh = "Brian McKenna <brian@brianmckenna.org>";
+  pxc = "Patrick Callahan <patrick.callahan@latitudeengineering.com>";
+  qknight = "Joachim Schiele <js@lastlog.de>";
+  ragge = "Ragnar Dahlen <r.dahlen@gmail.com>";
+  ralith = "Benjamin Saunders <ben.e.saunders@gmail.com>";
+  ramkromberg = "Ram Kromberg <ramkromberg@mail.com>";
+  rardiol = "Ricardo Ardissone <ricardo.ardissone@gmail.com>";
+  rasendubi = "Alexey Shmalko <rasen.dubi@gmail.com>";
+  raskin = "Michael Raskin <7c6f434c@mail.ru>";
+  rbasso = "Rafael Basso <rbasso@sharpgeeks.net>";
+  redbaron = "Maxim Ivanov <ivanov.maxim@gmail.com>";
+  redvers = "Redvers Davies <red@infect.me>";
+  refnil = "Martin Lavoie <broemartino@gmail.com>";
+  regnat = "Théophane Hufschmitt <regnat@regnat.ovh>";
+  relrod = "Ricky Elrod <ricky@elrod.me>";
+  renzo = "Renzo Carbonara <renzocarbonara@gmail.com>";
+  retrry = "Tadas Barzdžius <retrry@gmail.com>";
+  rick68 = "Wei-Ming Yang <rick68@gmail.com>";
+  rickynils = "Rickard Nilsson <rickynils@gmail.com>";
+  rlupton20 = "Richard Lupton <richard.lupton@gmail.com>";
+  rnhmjoj = "Michele Guerini Rocco <micheleguerinirocco@me.com>";
+  rob = "Rob Vermaas <rob.vermaas@gmail.com>";
+  robberer = "Longrin Wischnewski <robberer@freakmail.de>";
+  robbinch = "Robbin C. <robbinch33@gmail.com>";
+  robgssp = "Rob Glossop <robgssp@gmail.com>";
+  roblabla = "Robin Lambertz <robinlambertz+dev@gmail.com>";
+  roconnor = "Russell O'Connor <roconnor@theorem.ca>";
+  romildo = "José Romildo Malaquias <malaquias@gmail.com>";
+  rongcuid = "Rongcui Dong <rongcuid@outlook.com>";
+  ronny = "Ronny Pfannschmidt <nixos@ronnypfannschmidt.de>";
+  rszibele = "Richard Szibele <richard_szibele@hotmail.com>";
+  rtreffer = "Rene Treffer <treffer+nixos@measite.de>";
+  rushmorem = "Rushmore Mushambi <rushmore@webenchanter.com>";
+  rvl = "Rodney Lorrimar <dev+nix@rodney.id.au>";
+  rvlander = "Gaëtan André <rvlander@gaetanandre.eu>";
+  ryanartecona = "Ryan Artecona <ryanartecona@gmail.com>";
+  ryansydnor = "Ryan Sydnor <ryan.t.sydnor@gmail.com>";
+  ryantm = "Ryan Mulligan <ryan@ryantm.com>";
+  rycee = "Robert Helgesson <robert@rycee.net>";
+  ryneeverett = "Ryne Everett <ryneeverett@gmail.com>";
+  s1lvester = "Markus Silvester <s1lvester@bockhacker.me>";
+  samuelrivas = "Samuel Rivas <samuelrivas@gmail.com>";
+  sander = "Sander van der Burg <s.vanderburg@tudelft.nl>";
+  schmitthenner = "Fabian Schmitthenner <development@schmitthenner.eu>";
+  schneefux = "schneefux <schneefux+nixos_pkg@schneefux.xyz>";
+  schristo = "Scott Christopher <schristopher@konputa.com>";
+  scolobb = "Sergiu Ivanov <sivanov@colimite.fr>";
+  sepi = "Raffael Mancini <raffael@mancini.lu>";
+  seppeljordan = "Sebastian Jordan <sebastian.jordan.mail@googlemail.com>";
+  sheenobu = "Sheena Artrip <sheena.artrip@gmail.com>";
+  sheganinans = "Aistis Raulinaitis <sheganinans@gmail.com>";
+  shell = "Shell Turner <cam.turn@gmail.com>";
+  shlevy = "Shea Levy <shea@shealevy.com>";
+  siddharthist = "Langston Barrett <langston.barrett@gmail.com>";
+  simonvandel = "Simon Vandel Sillesen <simon.vandel@gmail.com>";
+  sjagoe = "Simon Jagoe <simon@simonjagoe.com>";
+  sjmackenzie = "Stewart Mackenzie <setori88@gmail.com>";
+  sjourdois = "Stéphane ‘kwisatz’ Jourdois <sjourdois@gmail.com>";
+  skeidel = "Sven Keidel <svenkeidel@gmail.com>";
+  skrzyp = "Jakub Skrzypnik <jot.skrzyp@gmail.com>";
+  sleexyz = "Sean Lee <freshdried@gmail.com>";
+  smironov = "Sergey Mironov <grrwlf@gmail.com>";
+  solson = "Scott Olson <scott@solson.me>";
+  spacefrogg = "Michael Raitza <spacefrogg-nixos@meterriblecrew.net>";
+  spencerjanssen = "Spencer Janssen <spencerjanssen@gmail.com>";
+  spinus = "Tomasz Czyż <tomasz.czyz@gmail.com>";
+  sprock = "Roger Mason <rmason@mun.ca>";
+  spwhitt = "Spencer Whitt <sw@swhitt.me>";
+  srhb = "Sarah Brofeldt <sbrofeldt@gmail.com>";
+  SShrike = "Severen Redwood <severen@shrike.me>";
+  stephenmw = "Stephen Weinberg <stephen@q5comm.com>";
+  sternenseemann = "Lukas Epple <post@lukasepple.de>";
+  stesie = "Stefan Siegl <stesie@brokenpipe.de>";
+  steveej = "Stefan Junker <mail@stefanjunker.de>";
+  swarren83 = "Shawn Warren <shawn.w.warren@gmail.com>";
+  swistak35 = "Rafał Łasocha <me@swistak35.com>";
+  szczyp = "Szczyp <qb@szczyp.com>";
+  sztupi = "Attila Sztupak <attila.sztupak@gmail.com>";
+  taeer = "Taeer Bar-Yam <taeer@necsi.edu>";
+  tailhook = "Paul Colomiets <paul@colomiets.name>";
+  takikawa = "Asumu Takikawa <asumu@igalia.com>";
+  taktoa = "Remy Goldschmidt <taktoa@gmail.com>";
+  tavyc = "Octavian Cerna <octavian.cerna@gmail.com>";
+  teh = "Tom Hunger <tehunger@gmail.com>";
+  telotortium = "Robert Irelan <rirelan@gmail.com>";
+  thall = "Niclas Thall <niclas.thall@gmail.com>";
+  thammers = "Tobias Hammerschmidt <jawr@gmx.de>";
+  the-kenny = "Moritz Ulrich <moritz@tarn-vedra.de>";
+  theuni = "Christian Theune <ct@flyingcircus.io>";
+  thoughtpolice = "Austin Seipp <aseipp@pobox.com>";
+  timbertson = "Tim Cuthbertson <tim@gfxmonk.net>";
+  titanous = "Jonathan Rudenberg <jonathan@titanous.com>";
+  tohl = "Tomas Hlavaty <tom@logand.com>";
+  tokudan = "Daniel Frank <git@danielfrank.net>";
+  tomberek = "Thomas Bereknyei <tomberek@gmail.com>";
+  travisbhartwell = "Travis B. Hartwell <nafai@travishartwell.net>";
+  trino = "Hubert Mühlhans <muehlhans.hubert@ekodia.de>";
+  tstrobel = "Thomas Strobel <4ZKTUB6TEP74PYJOPWIR013S2AV29YUBW5F9ZH2F4D5UMJUJ6S@hash.domains>";
+  ttuegel = "Thomas Tuegel <ttuegel@mailbox.org>";
+  tv = "Tomislav Viljetić <tv@shackspace.de>";
+  tvestelind = "Tomas Vestelind <tomas.vestelind@fripost.org>";
+  tvorog = "Marsel Zaripov <marszaripov@gmail.com>";
+  twey = "James ‘Twey’ Kay <twey@twey.co.uk>";
+  uralbash = "Svintsov Dmitry <root@uralbash.ru>";
+  urkud = "Yury G. Kudryashov <urkud+nix@ya.ru>";
+  uwap = "uwap <me@uwap.name>";
+  vandenoever = "Jos van den Oever <jos@vandenoever.info>";
+  vanzef = "Ivan Solyankin <vanzef@gmail.com>";
+  vbgl = "Vincent Laporte <Vincent.Laporte@gmail.com>";
+  vbmithr = "Vincent Bernardoff <vb@luminar.eu.org>";
+  vcunat = "Vladimír Čunát <vcunat@gmail.com>";
+  vdemeester = "Vincent Demeester <vincent@sbr.pm>";
+  veprbl = "Dmitry Kalinkin <veprbl@gmail.com>";
+  vifino = "Adrian Pistol <vifino@tty.sh>";
+  viric = "Lluís Batlle i Rossell <viric@viric.name>";
+  vizanto = "Danny Wilson <danny@prime.vc>";
+  vklquevs = "vklquevs <vklquevs@gmail.com>";
+  vlstill = "Vladimír Štill <xstill@fi.muni.cz>";
+  vmandela = "Venkateswara Rao Mandela <venkat.mandela@gmail.com>";
+  volhovm = "Mikhail Volkhov <volhovm.cs@gmail.com>";
+  volth = "Jaroslavas Pocepko <jaroslavas@volth.com>";
+  vozz = "Oliver Hunt <oliver.huntuk@gmail.com>";
+  vrthra = "Rahul Gopinath <rahul@gopinath.org>";
+  wedens = "wedens <kirill.wedens@gmail.com>";
+  willtim = "Tim Philip Williams <tim.williams.public@gmail.com>";
+  winden = "Antonio Vargas Gonzalez <windenntw@gmail.com>";
+  wizeman = "Ricardo M. Correia <rcorreia@wizy.org>";
+  wjlroe = "William Roe <willroe@gmail.com>";
+  wkennington = "William A. Kennington III <william@wkennington.com>";
+  wmertens = "Wout Mertens <Wout.Mertens@gmail.com>";
+  womfoo = "Kranium Gikos Mendoza <kranium@gikos.net>";
+  wscott = "Wayne Scott <wsc9tt@gmail.com>";
+  wyvie = "Elijah Rum <elijahrum@gmail.com>";
+  xwvvvvwx = "David Terry <davidterry@posteo.de>";
+  yarr = "Dmitry V. <savraz@gmail.com>";
+  yochai = "Yochai <yochai@titat.info>";
+  yorickvp = "Yorick van Pelt <yorickvanpelt@gmail.com>";
+  yurrriq = "Eric Bailey <eric@ericb.me>";
+  z77z = "Marco Maggesi <maggesi@math.unifi.it>";
+  zagy = "Christian Zagrodnick <cz@flyingcircus.io>";
+  zauberpony = "Elmar Athmer <elmar@athmer.org>";
+  zef = "Zef Hemel <zef@zef.me>";
+  zimbatm = "zimbatm <zimbatm@zimbatm.com>";
+  zohl = "Al Zohali <zohl@fmap.me>";
+  zoomulator = "Kim Simmons <zoomulator@gmail.com>";
+  zraexy = "David Mell <zraexy@gmail.com>";
+}
--- a/lib/meta.nix
+++ b/lib/meta.nix
@@ -1,7 +1,8 @@
 /* Some functions for manipulating meta attributes, as well as the
   name attribute. */

-{ lib }:
+let lib = import ./default.nix;
+in

 rec {

@@ -16,11 +17,6 @@ rec {
    drv // { meta = (drv.meta or {}) // newAttrs; };


-  /* Disable Hydra builds of given derivation.
-  */
-  dontDistribute = drv: addMetaAttrs { hydraPlatforms = []; } drv;
-
-
  /* Change the symbolic name of a package for presentation purposes
     (i.e., so that nix-env users can tell them apart).
  */
@@ -49,7 +45,7 @@ rec {
  /* Decrease the nix-env priority of the package, i.e., other
     versions/variants of the package will be preferred.
  */
-  lowPrio = drv: addMetaAttrs { priority = 10; } drv;
+  lowPrio = drv: addMetaAttrs { priority = "10"; } drv;


  /* Apply lowPrio to an attrset with derivations
@@ -60,7 +56,7 @@ rec {
  /* Increase the nix-env priority of the package, i.e., this
     version/variant of the package will be preferred.
  */
-  hiPrio = drv: addMetaAttrs { priority = -10; } drv;
+  hiPrio = drv: addMetaAttrs { priority = "-10"; } drv;


  /* Apply hiPrio to an attrset with derivations
--- a/lib/minver.nix
+++ b/lib/minver.nix
@@ -1,2 +1,2 @@
 # Expose the minimum required version for evaluating Nixpkgs
-"1.11"
+"1.10"
--- a/lib/modules.nix
+++ b/lib/modules.nix
@@ -1,12 +1,10 @@
-{ lib }:
-
-with lib.lists;
-with lib.strings;
-with lib.trivial;
-with lib.attrsets;
-with lib.options;
-with lib.debug;
-with lib.types;
+with import ./lists.nix;
+with import ./strings.nix;
+with import ./trivial.nix;
+with import ./attrsets.nix;
+with import ./options.nix;
+with import ./debug.nix;
+with import ./types.nix;

 rec {

@@ -22,8 +20,7 @@ rec {
                , prefix ? []
                , # This should only be used for special arguments that need to be evaluated
                  # when resolving module structure (like in imports). For everything else,
-                  # there's _module.args. If specialArgs.modulesPath is defined it will be
-                  # used as the base path for disabledModules.
+                  # there's _module.args.
                  specialArgs ? {}
                , # This would be remove in the future, Prefer _module.args option instead.
                  args ? {}
@@ -61,7 +58,10 @@ rec {

      closed = closeModules (modules ++ [ internalModule ]) ({ inherit config options; lib = import ./.; } // specialArgs);

-      options = mergeModules prefix (reverseList (filterModules (specialArgs.modulesPath or "") closed));
+      # Note: the list of modules is reversed to maintain backward
+      # compatibility with the old module system.  Not sure if this is
+      # the most sensible policy.
+      options = mergeModules prefix (reverseList closed);

      # Traverse options and extract the option values into the final
      # config set.  At the same time, check whether all option
@@ -87,20 +87,10 @@ rec {
      result = { inherit options config; };
    in result;

-
- # Filter disabled modules. Modules can be disabled allowing
- # their implementation to be replaced.
- filterModules = modulesPath: modules:
-   let
-     moduleKey = m: if isString m then toString modulesPath + "/" + m else toString m;
-     disabledKeys = map moduleKey (concatMap (m: m.disabledModules) modules);
-   in
-     filter (m: !(elem m.key disabledKeys)) modules;
-
  /* Close a set of modules under the ‘imports’ relation. */
  closeModules = modules: args:
    let
-      toClosureList = file: parentKey: imap1 (n: x:
+      toClosureList = file: parentKey: imap (n: x:
        if isAttrs x || isFunction x then
          let key = "${parentKey}:anon-${toString n}"; in
          unifyModuleSyntax file key (unpackSubmodule (applyIfFunction key) x args)
@@ -116,18 +106,17 @@ rec {
  /* Massage a module into canonical form, that is, a set consisting
     of ‘options’, ‘config’ and ‘imports’ attributes. */
  unifyModuleSyntax = file: key: m:
-    let metaSet = if m ? meta
+    let metaSet = if m ? meta 
      then { meta = m.meta; }
      else {};
    in
    if m ? config || m ? options then
-      let badAttrs = removeAttrs m ["_file" "key" "disabledModules" "imports" "options" "config" "meta"]; in
+      let badAttrs = removeAttrs m ["imports" "options" "config" "key" "_file" "meta"]; in
      if badAttrs != {} then
        throw "Module `${key}' has an unsupported attribute `${head (attrNames badAttrs)}'. This is caused by assignments to the top-level attributes `config' or `options'."
      else
        { file = m._file or file;
          key = toString m.key or key;
-          disabledModules = m.disabledModules or [];
          imports = m.imports or [];
          options = m.options or {};
          config = mkMerge [ (m.config or {}) metaSet ];
@@ -135,10 +124,9 @@ rec {
    else
      { file = m._file or file;
        key = toString m.key or key;
-        disabledModules = m.disabledModules or [];
        imports = m.require or [] ++ m.imports or [];
        options = {};
-        config = mkMerge [ (removeAttrs m ["_file" "key" "disabledModules" "require" "imports"]) metaSet ];
+        config = mkMerge [ (removeAttrs m ["key" "_file" "require" "imports"]) metaSet ];
      };

  applyIfFunction = key: f: args@{ config, options, lib, ... }: if isFunction f then
@@ -155,7 +143,7 @@ rec {
      # a module will resolve strictly the attributes used as argument but
      # not their values.  The values are forwarding the result of the
      # evaluation of the option.
-      requiredArgs = builtins.attrNames (lib.functionArgs f);
+      requiredArgs = builtins.attrNames (builtins.functionArgs f);
      context = name: ''while evaluating the module argument `${name}' in "${key}":'';
      extraArgs = builtins.listToAttrs (map (name: {
        inherit name;
@@ -338,7 +326,7 @@ rec {
    # Type-check the remaining definitions, and merge them.
    mergedValue = foldl' (res: def:
      if type.check def.value then res
-      else throw "The option value `${showOption loc}' in `${def.file}' is not of type `${type.description}'.")
+      else throw "The option value `${showOption loc}' in `${def.file}' is not a ${type.description}.")
      (type.merge loc defsFinal) defsFinal;

    isDefined = defsFinal != [];
@@ -425,7 +413,7 @@ rec {
    in concatMap (def: if getPrio def == highestPrio then [(strip def)] else []) defs;

  /* Sort a list of properties.  The sort priority of a property is
-     1000 by default, but can be overridden by wrapping the property
+     1000 by default, but can be overriden by wrapping the property
     using mkOrder. */
  sortProperties = defs:
    let
@@ -597,7 +585,7 @@ rec {
       functionality

     This show a warning if any a.b.c or d.e.f is set, and set the value of
-     x.y.z to the result of the merge function
+     x.y.z to the result of the merge function 
  */
  mkMergedOptionModule = from: to: mergeFn:
    { config, options, ... }:
@@ -613,12 +601,12 @@ rec {
          let val = getAttrFromPath f config;
              opt = getAttrFromPath f options;
          in
-          optionalString
+          optionalString 
            (val != "_mkMergedOptionModule")
            "The option `${showOption f}' defined in ${showFiles opt.files} has been changed to `${showOption to}' that has a different type. Please read `${showOption to}' documentation and update your configuration accordingly."
        ) from);
      } // setAttrByPath to (mkMerge
-             (optional
+             (optional 
               (any (f: (getAttrFromPath f config) != "_mkMergedOptionModule") from)
               (mergeFn config)));
    };
@@ -660,7 +648,7 @@ rec {
  doRename = { from, to, visible, warn, use }:
    let
      toOf = attrByPath to
-        (abort "Renaming error: option `${showOption to}' does not exist.");
+        (abort "Renaming error: option `${showOption to}' does not exists.");
    in
      { config, options, ... }:
      { options = setAttrByPath from (mkOption {
--- a/lib/options.nix
+++ b/lib/options.nix
@@ -1,10 +1,11 @@
 # Nixpkgs/NixOS option handling.
-{ lib }:

-with lib.trivial;
-with lib.lists;
-with lib.attrsets;
-with lib.strings;
+let lib = import ./default.nix; in
+
+with import ./trivial.nix;
+with import ./lists.nix;
+with import ./attrsets.nix;
+with import ./strings.nix;

 rec {

@@ -14,7 +15,6 @@ rec {
    , defaultText ? null # Textual representation of the default, for in the manual.
    , example ? null # Example value used in the manual.
    , description ? null # String describing the option.
-    , relatedPackages ? null # Related packages used in the manual (see `genRelatedPackages` in ../nixos/doc/manual/default.nix).
    , type ? null # Option type, providing type-checking and value merging.
    , apply ? null # Function that converts the option value to something else.
    , internal ? null # Whether the option is for NixOS developers only.
@@ -77,6 +77,7 @@ rec {
  getValues = map (x: x.value);
  getFiles = map (x: x.file);

+
  # Generate documentation template from the list of option declaration like
  # the set generated with filterOptionSets.
  optionAttrSetToDocList = optionAttrSetToDocList' [];
@@ -85,7 +86,6 @@ rec {
    concatMap (opt:
      let
        docOption = rec {
-          loc = opt.loc;
          name = showOption opt.loc;
          description = opt.description or (throw "Option `${name}' has no description.");
          declarations = filter (x: x != unknownModule) opt.declarations;
@@ -94,10 +94,9 @@ rec {
          readOnly = opt.readOnly or false;
          type = opt.type.description or null;
        }
-        // optionalAttrs (opt ? example) { example = scrubOptionValue opt.example; }
-        // optionalAttrs (opt ? default) { default = scrubOptionValue opt.default; }
-        // optionalAttrs (opt ? defaultText) { default = opt.defaultText; }
-        // optionalAttrs (opt ? relatedPackages && opt.relatedPackages != null) { inherit (opt) relatedPackages; };
+        // (if opt ? example then { example = scrubOptionValue opt.example; } else {})
+        // (if opt ? default then { default = scrubOptionValue opt.default; } else {})
+        // (if opt ? defaultText then { default = opt.defaultText; } else {});

        subOptions =
          let ss = opt.type.getSubOptions opt.loc;
--- a/lib/platforms.nix
+++ b/lib/platforms.nix
@@ -0,0 +1,24 @@
+let lists = import ./lists.nix; in
+
+rec {
+  all = linux ++ darwin ++ cygwin ++ freebsd ++ openbsd ++ netbsd ++ illumos;
+  allBut = platforms: lists.filter (x: !(builtins.elem x platforms)) all;
+  none = [];
+
+  arm = ["armv5tel-linux" "armv6l-linux" "armv7l-linux" ];
+  i686 = ["i686-linux" "i686-freebsd" "i686-netbsd" "i686-cygwin"];
+  mips = [ "mips64el-linux" ];
+  x86_64 = ["x86_64-linux" "x86_64-darwin" "x86_64-freebsd" "x86_64-openbsd" "x86_64-netbsd" "x86_64-cygwin"];
+
+  cygwin = ["i686-cygwin" "x86_64-cygwin"];
+  darwin = ["x86_64-darwin"];
+  freebsd = ["i686-freebsd" "x86_64-freebsd"];
+  gnu = linux; /* ++ hurd ++ kfreebsd ++ ... */
+  illumos = ["x86_64-solaris"];
+  linux = ["i686-linux" "x86_64-linux" "armv5tel-linux" "armv6l-linux" "armv7l-linux" "aarch64-linux" "mips64el-linux"];
+  netbsd = ["i686-netbsd" "x86_64-netbsd"];
+  openbsd = ["i686-openbsd" "x86_64-openbsd"];
+  unix = linux ++ darwin ++ freebsd ++ openbsd ++ netbsd ++ illumos;
+
+  mesaPlatforms = ["i686-linux" "x86_64-linux" "x86_64-darwin" "armv5tel-linux" "armv6l-linux" "armv7l-linux" "aarch64-linux"];
+}
--- a/lib/sandbox.nix
+++ b/lib/sandbox.nix
@@ -0,0 +1,47 @@
+with import ./strings.nix;
+
+/* Helpers for creating lisp S-exprs for the Apple sandbox
+
+lib.sandbox.allowFileRead [ "/usr/bin/file" ];
+  # => "(allow file-read* (literal \"/usr/bin/file\"))";
+
+lib.sandbox.allowFileRead {
+  literal = [ "/usr/bin/file" ];
+  subpath = [ "/usr/lib/system" ];
+}
+  # => "(allow file-read* (literal \"/usr/bin/file\") (subpath \"/usr/lib/system\"))"
+*/
+
+let
+
+sexp = tokens: "(" + builtins.concatStringsSep " " tokens + ")";
+generateFileList = files:
+  if builtins.isList files
+    then concatMapStringsSep " " (x: sexp [ "literal" ''"${x}"'' ]) files
+    else if builtins.isString files
+      then generateFileList [ files ]
+      else concatStringsSep " " (
+        (map (x: sexp [ "literal" ''"${x}"'' ]) (files.literal or [])) ++
+        (map (x: sexp [ "subpath" ''"${x}"'' ]) (files.subpath or []))
+      );
+applyToFiles = f: act: files: f "${act} ${generateFileList files}";
+genActions = actionName: let
+  action = feature: sexp [ actionName feature ];
+  self = {
+    "${actionName}" = action;
+    "${actionName}File" = applyToFiles action "file*";
+    "${actionName}FileRead" = applyToFiles action "file-read*";
+    "${actionName}FileReadMetadata" = applyToFiles action "file-read-metadata";
+    "${actionName}DirectoryList" = self."${actionName}FileReadMetadata";
+    "${actionName}FileWrite" = applyToFiles action "file-write*";
+    "${actionName}FileWriteMetadata" = applyToFiles action "file-write-metadata";
+  };
+  in self;
+
+in
+
+genActions "allow" // genActions "deny" // {
+  importProfile = derivation: ''
+    (import "${derivation}")
+  '';
+}
--- a/lib/sources.nix
+++ b/lib/sources.nix
@@ -1,5 +1,6 @@
 # Functions for copying sources to the Nix store.
-{ lib }:
+
+let lib = import ./default.nix; in

 rec {

@@ -14,11 +15,8 @@ rec {
  cleanSourceFilter = name: type: let baseName = baseNameOf (toString name); in ! (
    # Filter out Subversion and CVS directories.
    (type == "directory" && (baseName == ".git" || baseName == ".svn" || baseName == "CVS" || baseName == ".hg")) ||
-    # Filter out editor backup / swap files.
+    # Filter out backup files.
    lib.hasSuffix "~" baseName ||
-    builtins.match "^\\.sw[a-z]$" baseName != null ||
-    builtins.match "^\\..*\\.sw[a-z]$" baseName != null ||
-
    # Filter out generates files.
    lib.hasSuffix ".o" baseName ||
    lib.hasSuffix ".so" baseName ||
@@ -26,35 +24,14 @@ rec {
    (type == "symlink" && lib.hasPrefix "result" baseName)
  );

-  cleanSource = src: cleanSourceWith { filter = cleanSourceFilter; inherit src; };
-
-  # Like `builtins.filterSource`, except it will compose with itself,
-  # allowing you to chain multiple calls together without any
-  # intermediate copies being put in the nix store.
-  #
-  #     lib.cleanSourceWith f (lib.cleanSourceWith g ./.)     # Succeeds!
-  #     builtins.filterSource f (builtins.filterSource g ./.) # Fails!
-  cleanSourceWith = { filter, src }:
-    let
-      isFiltered = src ? _isLibCleanSourceWith;
-      origSrc = if isFiltered then src.origSrc else src;
-      filter' = if isFiltered then name: type: filter name type && src.filter name type else filter;
-    in {
-      inherit origSrc;
-      filter = filter';
-      outPath = builtins.filterSource filter' origSrc;
-      _isLibCleanSourceWith = true;
-    };
+  cleanSource = builtins.filterSource cleanSourceFilter;

  # Filter sources by a list of regular expressions.
  #
  # E.g. `src = sourceByRegex ./my-subproject [".*\.py$" "^database.sql$"]`
-  sourceByRegex = src: regexes: cleanSourceWith {
-    filter = (path: type:
-      let relPath = lib.removePrefix (toString src + "/") (toString path);
-      in lib.any (re: builtins.match re relPath != null) regexes);
-    inherit src;
-  };
+  sourceByRegex = src: regexes: builtins.filterSource (path: type:
+    let relPath = lib.removePrefix (toString src + "/") (toString path);
+    in lib.any (re: builtins.match re relPath != null) regexes) src;

  # Get all files ending with the specified suffices from the given
  # directory or its descendants.  E.g. `sourceFilesBySuffices ./dir
@@ -63,7 +40,7 @@ rec {
    let filter = name: type:
      let base = baseNameOf (toString name);
      in type == "directory" || lib.any (ext: lib.hasSuffix ext base) exts;
-    in cleanSourceWith { inherit filter; src = path; };
+    in builtins.filterSource filter path;


  # Get the commit id of a git repo
@@ -93,8 +70,4 @@ rec {
                else lib.head matchRef
           else throw ("Not a .git directory: " + path);
    in lib.flip readCommitFromFile "HEAD";
-
-  pathHasContext = builtins.hasContext or (lib.hasPrefix builtins.storeDir);
-
-  canCleanSource = src: src ? _isLibCleanSourceWith || !(pathHasContext (toString src));
 }
--- a/lib/strings-with-deps.nix
+++ b/lib/strings-with-deps.nix
@@ -1,4 +1,3 @@
-{ lib }:
 /*
 Usage:

@@ -41,9 +40,9 @@ Usage:
  [1] maybe this behaviour should be removed to keep things simple (?)
 */

-with lib.lists;
-with lib.attrsets;
-with lib.strings;
+with import ./lists.nix;
+with import ./attrsets.nix;
+with import ./strings.nix;

 rec {

--- a/lib/strings.nix
+++ b/lib/strings.nix
@@ -1,6 +1,6 @@
 /* String manipulation functions. */
-{ lib }:
-let
+
+let lib = import ./default.nix;

 inherit (builtins) length;

@@ -33,7 +33,7 @@ rec {
       concatImapStrings (pos: x: "${toString pos}-${x}") ["foo" "bar"]
       => "1-foo2-bar"
  */
-  concatImapStrings = f: list: concatStrings (lib.imap1 f list);
+  concatImapStrings = f: list: concatStrings (lib.imap f list);

  /* Place an element between each element of a list

@@ -70,7 +70,7 @@ rec {
       concatImapStringsSep "-" (pos: x: toString (x / pos)) [ 6 6 6 ]
       => "6-3-2"
  */
-  concatImapStringsSep = sep: f: list: concatStringsSep sep (lib.imap1 f list);
+  concatImapStringsSep = sep: f: list: concatStringsSep sep (lib.imap f list);

  /* Construct a Unix-style search path consisting of each `subDir"
     directory of the given list of packages.
@@ -126,8 +126,8 @@ rec {
  */
  makePerlPath = makeSearchPathOutput "lib" "lib/perl5/site_perl";

-  /* Depending on the boolean `cond', return either the given string
-     or the empty string. Useful to concatenate against a bigger string.
+  /* Dependening on the boolean `cond', return either the given string
+     or the empty string. Useful to contatenate against a bigger string.

     Example:
       optionalString true "some-string"
@@ -219,14 +219,6 @@ rec {
  */
  escapeShellArgs = concatMapStringsSep " " escapeShellArg;

-  /* Turn a string into a Nix expression representing that string
-
-     Example:
-       escapeNixString "hello\${}\n"
-       => "\"hello\\\${}\\n\""
-  */
-  escapeNixString = s: escape ["$"] (builtins.toJSON s);
-
  /* Obsolete - use replaceStrings instead. */
  replaceChars = builtins.replaceStrings or (
    del: new: s:
@@ -299,7 +291,7 @@ rec {

      recurse = index: startAt:
        let cutUntil = i: [(substring startAt (i - startAt) s)]; in
-        if index <= lastSearch then
+        if index < lastSearch then
          if startWithSep index then
            let restartAt = index + sepLen; in
            cutUntil index ++ recurse restartAt restartAt
@@ -446,13 +438,8 @@ rec {
       => true
       isStorePath pkgs.python
       => true
-       isStorePath [] || isStorePath 42 || isStorePath {} || …
-       => false
  */
-  isStorePath = x:
-       builtins.isString x
-    && builtins.substring 0 1 (toString x) == "/"
-    && dirOf (builtins.toPath x) == builtins.storeDir;
+  isStorePath = x: builtins.substring 0 1 (toString x) == "/" && dirOf (builtins.toPath x) == builtins.storeDir;

  /* Convert string to int
     Obviously, it is a bit hacky to use fromJSON that way.
@@ -489,8 +476,10 @@ rec {
  readPathsFromFile = rootPath: file:
    let
      root = toString rootPath;
-      lines = lib.splitString "\n" (builtins.readFile file);
-      removeComments = lib.filter (line: line != "" && !(lib.hasPrefix "#" line));
+      lines =
+        builtins.map (lib.removeSuffix "\n")
+        (lib.splitString "\n" (builtins.readFile file));
+      removeComments = lib.filter (line: !(lib.hasPrefix "#" line));
      relativePaths = removeComments lines;
      absolutePaths = builtins.map (path: builtins.toPath (root + "/" + path)) relativePaths;
    in
--- a/lib/systems.nix
+++ b/lib/systems.nix
@@ -0,0 +1,126 @@
+# Define the list of system with their properties.  Only systems tested for
+# Nixpkgs are listed below
+
+with import ./lists.nix;
+with import ./types.nix;
+with import ./attrsets.nix;
+
+let
+  lib = import ./default.nix;
+  setTypes = type:
+    mapAttrs (name: value:
+      setType type ({inherit name;} // value)
+    );
+in
+
+rec {
+
+  isSignificantByte = isType "significant-byte";
+  significantBytes = setTypes "significant-byte" {
+    bigEndian = {};
+    littleEndian = {};
+  };
+
+
+  isCpuType = x: isType "cpu-type" x
+    && elem x.bits [8 16 32 64 128]
+    && (8 < x.bits -> isSignificantByte x.significantByte);
+
+  cpuTypes = with significantBytes;
+    setTypes "cpu-type" {
+      arm =      { bits = 32; significantByte = littleEndian; };
+      armv5tel = { bits = 32; significantByte = littleEndian; };
+      armv7l   = { bits = 32; significantByte = littleEndian; };
+      i686 =     { bits = 32; significantByte = littleEndian; };
+      powerpc =  { bits = 32; significantByte = bigEndian; };
+      x86_64 =   { bits = 64; significantByte = littleEndian; };
+    };
+
+
+  isExecFormat = isType "exec-format";
+  execFormats = setTypes "exec-format" {
+    aout = {}; # a.out
+    elf = {};
+    macho = {};
+    pe = {};
+    unknow = {};
+  };
+
+
+  isKernel = isType "kernel";
+  kernels = with execFormats;
+    setTypes "kernel" {
+      cygwin =  { execFormat = pe; };
+      darwin =  { execFormat = macho; };
+      freebsd = { execFormat = elf; };
+      linux =   { execFormat = elf; };
+      netbsd =  { execFormat = elf; };
+      none =    { execFormat = unknow; };
+      openbsd = { execFormat = elf; };
+      win32 =   { execFormat = pe; };
+    };
+
+
+  isArchitecture = isType "architecture";
+  architectures = setTypes "architecture" {
+    apple = {};
+    pc = {};
+    unknow = {};
+  };
+
+
+  isSystem = x: isType "system" x
+    && isCpuType x.cpu
+    && isArchitecture x.arch
+    && isKernel x.kernel;
+
+  mkSystem = {
+    cpu ? cpuTypes.i686,
+    arch ? architectures.pc,
+    kernel ? kernels.linux,
+    name ? "${cpu.name}-${arch.name}-${kernel.name}"
+  }: setType "system" {
+    inherit name cpu arch kernel;
+  };
+
+
+  is64Bit = matchAttrs { cpu = { bits = 64; }; };
+  isDarwin = matchAttrs { kernel = kernels.darwin; };
+  isi686 = matchAttrs { cpu = cpuTypes.i686; };
+  isLinux = matchAttrs { kernel = kernels.linux; };
+
+
+  # This should revert the job done by config.guess from the gcc compiler.
+  mkSystemFromString = s: let
+    l = lib.splitString "-" s;
+
+    getCpu = name:
+      attrByPath [name] (throw "Unknow cpuType `${name}'.")
+        cpuTypes;
+    getArch = name:
+      attrByPath [name] (throw "Unknow architecture `${name}'.")
+        architectures;
+    getKernel = name:
+      attrByPath [name] (throw "Unknow kernel `${name}'.")
+        kernels;
+
+    system =
+      if builtins.length l == 2 then
+        mkSystem rec {
+          name = s;
+          cpu = getCpu (head l);
+          arch =
+            if isDarwin system
+            then architectures.apple
+            else architectures.pc;
+          kernel = getKernel (head (tail l));
+        }
+      else
+        mkSystem {
+          name = s;
+          cpu = getCpu (head l);
+          arch = getArch (head (tail l));
+          kernel = getKernel (head (tail (tail l)));
+        };
+  in assert isSystem system; system;
+}
--- a/lib/systems/default.nix
+++ b/lib/systems/default.nix
@@ -1,50 +0,0 @@
-{ lib }:
-  let inherit (lib.attrsets) mapAttrs; in
-
-rec {
-  doubles = import ./doubles.nix { inherit lib; };
-  parse = import ./parse.nix { inherit lib; };
-  inspect = import ./inspect.nix { inherit lib; };
-  platforms = import ./platforms.nix { inherit lib; };
-  examples = import ./examples.nix { inherit lib; };
-
-  # Elaborate a `localSystem` or `crossSystem` so that it contains everything
-  # necessary.
-  #
-  # `parsed` is inferred from args, both because there are two options with one
-  # clearly prefered, and to prevent cycles. A simpler fixed point where the RHS
-  # always just used `final.*` would fail on both counts.
-  elaborate = args: let
-    final = {
-      # Prefer to parse `config` as it is strictly more informative.
-      parsed = parse.mkSystemFromString (if args ? config then args.config else args.system);
-      # Either of these can be losslessly-extracted from `parsed` iff parsing succeeds.
-      system = parse.doubleFromSystem final.parsed;
-      config = parse.tripleFromSystem final.parsed;
-      # Just a guess, based on `system`
-      platform = platforms.selectBySystem final.system;
-      # Derived meta-data
-      libc =
-        /**/ if final.isDarwin              then "libSystem"
-        else if final.isMinGW               then "msvcrt"
-        else if final.isMusl                then "musl"
-        else if final.isAndroid             then "bionic"
-        else if final.isLinux /* default */ then "glibc"
-        # TODO(@Ericson2314) think more about other operating systems
-        else                                     "native/impure";
-      extensions = {
-        sharedLibrary =
-          /**/ if final.isDarwin  then ".dylib"
-          else if final.isWindows then ".dll"
-          else                         ".so";
-        executable =
-          /**/ if final.isWindows then ".exe"
-          else                         "";
-      };
-      # Misc boolean options
-      useAndroidPrebuilt = false;
-    } // mapAttrs (n: v: v final.parsed) inspect.predicates
-      // args;
-  in assert final.useAndroidPrebuilt -> final.isAndroid;
-    final;
-}
--- a/lib/systems/doubles.nix
+++ b/lib/systems/doubles.nix
@@ -1,47 +0,0 @@
-{ lib }:
-let
-  inherit (lib) lists;
-  inherit (lib.systems) parse;
-  inherit (lib.systems.inspect) predicates;
-  inherit (lib.attrsets) matchAttrs;
-
-  all = [
-    "aarch64-linux"
-    "armv5tel-linux" "armv6l-linux" "armv7l-linux"
-
-    "mipsel-linux"
-
-    "i686-cygwin" "i686-freebsd" "i686-linux" "i686-netbsd" "i686-openbsd"
-
-    "x86_64-cygwin" "x86_64-darwin" "x86_64-freebsd" "x86_64-linux"
-    "x86_64-netbsd" "x86_64-openbsd" "x86_64-solaris"
-  ];
-
-  allParsed = map parse.mkSystemFromString all;
-
-  filterDoubles = f: map parse.doubleFromSystem (lists.filter f allParsed);
-
-in rec {
-  inherit all;
-
-  allBut = platforms: lists.filter (x: !(builtins.elem x platforms)) all;
-  none = [];
-
-  arm     = filterDoubles predicates.isArm;
-  i686    = filterDoubles predicates.isi686;
-  mips    = filterDoubles predicates.isMips;
-  x86_64  = filterDoubles predicates.isx86_64;
-
-  cygwin  = filterDoubles predicates.isCygwin;
-  darwin  = filterDoubles predicates.isDarwin;
-  freebsd = filterDoubles predicates.isFreeBSD;
-  # Should be better, but MinGW is unclear, and HURD is bit-rotted.
-  gnu     = filterDoubles (matchAttrs { kernel = parse.kernels.linux;  abi = parse.abis.gnu; });
-  illumos = filterDoubles predicates.isSunOS;
-  linux   = filterDoubles predicates.isLinux;
-  netbsd  = filterDoubles predicates.isNetBSD;
-  openbsd = filterDoubles predicates.isOpenBSD;
-  unix    = filterDoubles predicates.isUnix;
-
-  mesaPlatforms = ["i686-linux" "x86_64-linux" "x86_64-darwin" "armv5tel-linux" "armv6l-linux" "armv7l-linux" "aarch64-linux"];
-}
--- a/lib/systems/examples.nix
+++ b/lib/systems/examples.nix
@@ -1,124 +0,0 @@
-# These can be passed to nixpkgs as either the `localSystem` or
-# `crossSystem`. They are put here for user convenience, but also used by cross
-# tests and linux cross stdenv building, so handle with care!
-{ lib }:
-let platforms = import ./platforms.nix { inherit lib; }; in
-
-rec {
-  #
-  # Linux
-  #
-
-  sheevaplug = rec {
-    config = "armv5tel-unknown-linux-gnueabi";
-    arch = "armv5tel";
-    float = "soft";
-    platform = platforms.sheevaplug;
-  };
-
-  raspberryPi = rec {
-    config = "armv6l-unknown-linux-gnueabihf";
-    arch = "armv6l";
-    float = "hard";
-    fpu = "vfp";
-    platform = platforms.raspberrypi;
-  };
-
-  armv7l-hf-multiplatform = rec {
-    config = "arm-unknown-linux-gnueabihf";
-    arch = "armv7-a";
-    float = "hard";
-    fpu = "vfpv3-d16";
-    platform = platforms.armv7l-hf-multiplatform;
-  };
-
-  aarch64-multiplatform = rec {
-    config = "aarch64-unknown-linux-gnu";
-    arch = "aarch64";
-    platform = platforms.aarch64-multiplatform;
-  };
-
-  aarch64-android-prebuilt = rec {
-    config = "aarch64-unknown-linux-android";
-    arch = "aarch64";
-    platform = platforms.aarch64-multiplatform;
-    useAndroidPrebuilt = true;
-  };
-
-  scaleway-c1 = armv7l-hf-multiplatform // rec {
-    platform = platforms.scaleway-c1;
-    inherit (platform.gcc) fpu;
-  };
-
-  pogoplug4 = rec {
-    arch = "armv5tel";
-    config = "armv5tel-unknown-linux-gnueabi";
-    float = "soft";
-    platform = platforms.pogoplug4;
-  };
-
-  fuloongminipc = rec {
-    config = "mipsel-unknown-linux-gnu";
-    arch = "mips";
-    float = "hard";
-    platform = platforms.fuloong2f_n32;
-  };
-
-  muslpi = raspberryPi // {
-    config = "armv6l-unknown-linux-musleabihf";
-  };
-
-  aarch64-multiplatform-musl = aarch64-multiplatform // {
-    config = "aarch64-unknown-linux-musl";
-  };
-
-  musl64 = { config = "x86_64-unknown-linux-musl"; };
-  musl32  = { config = "i686-unknown-linux-musl"; };
-
-  riscv = bits: {
-    config = "riscv${bits}-unknown-linux-gnu";
-    platform = platforms.riscv-multiplatform bits;
-  };
-  riscv64 = riscv "64";
-  riscv32 = riscv "32";
-
-
-  #
-  # Darwin
-  #
-
-  iphone64 = {
-    config = "aarch64-apple-darwin14";
-    arch = "arm64";
-    libc = "libSystem";
-    platform = {};
-  };
-
-  iphone32 = {
-    config = "arm-apple-darwin10";
-    arch = "armv7-a";
-    libc = "libSystem";
-    platform = {};
-  };
-
-  #
-  # Windows
-  #
-
-  # 32 bit mingw-w64
-  mingw32 = {
-    config = "i686-pc-mingw32";
-    arch = "x86"; # Irrelevant
-    libc = "msvcrt"; # This distinguishes the mingw (non posix) toolchain
-    platform = {};
-  };
-
-  # 64 bit mingw-w64
-  mingwW64 = {
-    # That's the triplet they use in the mingw-w64 docs.
-    config = "x86_64-pc-mingw32";
-    arch = "x86_64"; # Irrelevant
-    libc = "msvcrt"; # This distinguishes the mingw (non posix) toolchain
-    platform = {};
-  };
-}
--- a/lib/systems/inspect.nix
+++ b/lib/systems/inspect.nix
@@ -1,55 +0,0 @@
-{ lib }:
-with import ./parse.nix { inherit lib; };
-with lib.attrsets;
-with lib.lists;
-
-rec {
-  patterns = rec {
-    i686         = { cpu = cpuTypes.i686; };
-    x86_64       = { cpu = cpuTypes.x86_64; };
-    PowerPC      = { cpu = cpuTypes.powerpc; };
-    x86          = { cpu = { family = "x86"; }; };
-    Arm          = { cpu = { family = "arm"; }; };
-    Aarch64      = { cpu = { family = "aarch64"; }; };
-    Mips         = { cpu = { family = "mips"; }; };
-    RiscV        = { cpu = { family = "riscv"; }; };
-    Wasm         = { cpu = { family = "wasm"; }; };
-
-    "32bit"      = { cpu = { bits = 32; }; };
-    "64bit"      = { cpu = { bits = 64; }; };
-    BigEndian    = { cpu = { significantByte = significantBytes.bigEndian; }; };
-    LittleEndian = { cpu = { significantByte = significantBytes.littleEndian; }; };
-
-    BSD          = { kernel = { families = { inherit (kernelFamilies) bsd; }; }; };
-    Unix         = [ BSD Darwin Linux SunOS Hurd Cygwin ];
-
-    Darwin       = { kernel = kernels.darwin; };
-    Linux        = { kernel = kernels.linux; };
-    SunOS        = { kernel = kernels.solaris; };
-    FreeBSD      = { kernel = kernels.freebsd; };
-    Hurd         = { kernel = kernels.hurd; };
-    NetBSD       = { kernel = kernels.netbsd; };
-    OpenBSD      = { kernel = kernels.openbsd; };
-    Windows      = { kernel = kernels.windows; };
-    Cygwin       = { kernel = kernels.windows; abi = abis.cygnus; };
-    MinGW        = { kernel = kernels.windows; abi = abis.gnu; };
-
-    Android      = [ { abi = abis.android; } { abi = abis.androideabi; } ];
-    Musl         = with abis; map (a: { abi = a; }) [ musl musleabi musleabihf ];
-
-    Kexecable    = map (family: { kernel = kernels.linux; cpu.family = family; })
-                     [ "x86" "arm" "aarch64" "mips" ];
-    Efi          = map (family: { cpu.family = family; })
-                     [ "x86" "arm" "aarch64" ];
-    Seccomputable = map (family: { kernel = kernels.linux; cpu.family = family; })
-                      [ "x86" "arm" "aarch64" "mips" ];
-  };
-
-  matchAnyAttrs = patterns:
-    if builtins.isList patterns then attrs: any (pattern: matchAttrs pattern attrs) patterns
-    else matchAttrs patterns;
-
-  predicates = mapAttrs'
-    (name: value: nameValuePair ("is" + name) (matchAnyAttrs value))
-    patterns;
-}
--- a/lib/systems/parse.nix
+++ b/lib/systems/parse.nix
@@ -1,276 +0,0 @@
-# Define the list of system with their properties.
-#
-# See https://clang.llvm.org/docs/CrossCompilation.html and
-# http://llvm.org/docs/doxygen/html/Triple_8cpp_source.html especially
-# Triple::normalize. Parsing should essentially act as a more conservative
-# version of that last function.
-#
-# Most of the types below come in "open" and "closed" pairs. The open ones
-# specify what information we need to know about systems in general, and the
-# closed ones are sub-types representing the whitelist of systems we support in
-# practice.
-#
-# Code in the remainder of nixpkgs shouldn't rely on the closed ones in
-# e.g. exhaustive cases. Its more a sanity check to make sure nobody defines
-# systems that overlap with existing ones and won't notice something amiss.
-#
-{ lib }:
-with lib.lists;
-with lib.types;
-with lib.attrsets;
-with (import ./inspect.nix { inherit lib; }).predicates;
-
-let
-  inherit (lib.options) mergeOneOption;
-
-  setTypes = type:
-    mapAttrs (name: value:
-      assert type.check value;
-      setType type.name ({ inherit name; } // value));
-
-in
-
-rec {
-
-  ################################################################################
-
-  types.openSignifiantByte = mkOptionType {
-    name = "significant-byte";
-    description = "Endianness";
-    merge = mergeOneOption;
-  };
-
-  types.significantByte = enum (attrValues significantBytes);
-
-  significantBytes = setTypes types.openSignifiantByte {
-    bigEndian = {};
-    littleEndian = {};
-  };
-
-  ################################################################################
-
-  # Reasonable power of 2
-  types.bitWidth = enum [ 8 16 32 64 128 ];
-
-  ################################################################################
-
-  types.openCpuType = mkOptionType {
-    name = "cpu-type";
-    description = "instruction set architecture name and information";
-    merge = mergeOneOption;
-    check = x: types.bitWidth.check x.bits
-      && (if 8 < x.bits
-          then types.significantByte.check x.significantByte
-          else !(x ? significantByte));
-  };
-
-  types.cpuType = enum (attrValues cpuTypes);
-
-  cpuTypes = with significantBytes; setTypes types.openCpuType {
-    arm      = { bits = 32; significantByte = littleEndian; family = "arm"; };
-    armv5tel = { bits = 32; significantByte = littleEndian; family = "arm"; };
-    armv6l   = { bits = 32; significantByte = littleEndian; family = "arm"; };
-    armv7a   = { bits = 32; significantByte = littleEndian; family = "arm"; };
-    armv7l   = { bits = 32; significantByte = littleEndian; family = "arm"; };
-    aarch64  = { bits = 64; significantByte = littleEndian; family = "aarch64"; };
-    i686     = { bits = 32; significantByte = littleEndian; family = "x86"; };
-    x86_64   = { bits = 64; significantByte = littleEndian; family = "x86"; };
-    mips     = { bits = 32; significantByte = bigEndian;    family = "mips"; };
-    mipsel   = { bits = 32; significantByte = littleEndian; family = "mips"; };
-    mips64   = { bits = 64; significantByte = bigEndian;    family = "mips"; };
-    mips64el = { bits = 64; significantByte = littleEndian; family = "mips"; };
-    powerpc  = { bits = 32; significantByte = bigEndian;    family = "power"; };
-    riscv32  = { bits = 32; significantByte = littleEndian; family = "riscv"; };
-    riscv64  = { bits = 64; significantByte = littleEndian; family = "riscv"; };
-    wasm32   = { bits = 32; significantByte = littleEndian; family = "wasm"; };
-    wasm64   = { bits = 64; significantByte = littleEndian; family = "wasm"; };
-  };
-
-  ################################################################################
-
-  types.openVendor = mkOptionType {
-    name = "vendor";
-    description = "vendor for the platform";
-    merge = mergeOneOption;
-  };
-
-  types.vendor = enum (attrValues vendors);
-
-  vendors = setTypes types.openVendor {
-    apple = {};
-    pc = {};
-
-    unknown = {};
-  };
-
-  ################################################################################
-
-  types.openExecFormat = mkOptionType {
-    name = "exec-format";
-    description = "executable container used by the kernel";
-    merge = mergeOneOption;
-  };
-
-  types.execFormat = enum (attrValues execFormats);
-
-  execFormats = setTypes types.openExecFormat {
-    aout = {}; # a.out
-    elf = {};
-    macho = {};
-    pe = {};
-
-    unknown = {};
-  };
-
-  ################################################################################
-
-  types.openKernelFamily = mkOptionType {
-    name = "exec-format";
-    description = "executable container used by the kernel";
-    merge = mergeOneOption;
-  };
-
-  types.kernelFamily = enum (attrValues kernelFamilies);
-
-  kernelFamilies = setTypes types.openKernelFamily {
-    bsd = {};
-  };
-
-  ################################################################################
-
-  types.openKernel = mkOptionType {
-    name = "kernel";
-    description = "kernel name and information";
-    merge = mergeOneOption;
-    check = x: types.execFormat.check x.execFormat
-        && all types.kernelFamily.check (attrValues x.families);
-  };
-
-  types.kernel = enum (attrValues kernels);
-
-  kernels = with execFormats; with kernelFamilies; setTypes types.openKernel {
-    darwin  = { execFormat = macho;   families = { }; };
-    freebsd = { execFormat = elf;     families = { inherit bsd; }; };
-    hurd    = { execFormat = elf;     families = { }; };
-    linux   = { execFormat = elf;     families = { }; };
-    netbsd  = { execFormat = elf;     families = { inherit bsd; }; };
-    none    = { execFormat = unknown; families = { }; };
-    openbsd = { execFormat = elf;     families = { inherit bsd; }; };
-    solaris = { execFormat = elf;     families = { }; };
-    windows = { execFormat = pe;      families = { }; };
-  } // { # aliases
-    # TODO(@Ericson2314): Handle these Darwin version suffixes more generally.
-    darwin10 = kernels.darwin;
-    darwin14 = kernels.darwin;
-    win32 = kernels.windows;
-  };
-
-  ################################################################################
-
-  types.openAbi = mkOptionType {
-    name = "abi";
-    description = "binary interface for compiled code and syscalls";
-    merge = mergeOneOption;
-  };
-
-  types.abi = enum (attrValues abis);
-
-  abis = setTypes types.openAbi {
-    android = {};
-    cygnus = {};
-    gnu = {};
-    msvc = {};
-    eabi = {};
-    androideabi = {};
-    gnueabi = {};
-    gnueabihf = {};
-    musleabi = {};
-    musleabihf = {};
-    musl = {};
-
-    unknown = {};
-  };
-
-  ################################################################################
-
-  types.system = mkOptionType {
-    name = "system";
-    description = "fully parsed representation of llvm- or nix-style platform tuple";
-    merge = mergeOneOption;
-    check = { cpu, vendor, kernel, abi }:
-           types.cpuType.check cpu
-        && types.vendor.check vendor
-        && types.kernel.check kernel
-        && types.abi.check abi;
-  };
-
-  isSystem = isType "system";
-
-  mkSystem = components:
-    assert types.system.check components;
-    setType "system" components;
-
-  mkSkeletonFromList = l: {
-    "2" = # We only do 2-part hacks for things Nix already supports
-      if elemAt l 1 == "cygwin"
-        then { cpu = elemAt l 0;                      kernel = "windows";  abi = "cygnus";   }
-      else if elemAt l 1 == "gnu"
-        then { cpu = elemAt l 0;                      kernel = "hurd";     abi = "gnu";      }
-      else   { cpu = elemAt l 0;                      kernel = elemAt l 1;                   };
-    "3" = # Awkwards hacks, beware!
-      if elemAt l 1 == "apple"
-        then { cpu = elemAt l 0; vendor = "apple";    kernel = elemAt l 2;                   }
-      else if (elemAt l 1 == "linux") || (elemAt l 2 == "gnu")
-        then { cpu = elemAt l 0;                      kernel = elemAt l 1; abi = elemAt l 2; }
-      else if (elemAt l 2 == "mingw32") # autotools breaks on -gnu for window
-        then { cpu = elemAt l 0; vendor = elemAt l 1; kernel = "windows";  abi = "gnu"; }
-      else throw "Target specification with 3 components is ambiguous";
-    "4" =    { cpu = elemAt l 0; vendor = elemAt l 1; kernel = elemAt l 2; abi = elemAt l 3; };
-  }.${toString (length l)}
-    or (throw "system string has invalid number of hyphen-separated components");
-
-  # This should revert the job done by config.guess from the gcc compiler.
-  mkSystemFromSkeleton = { cpu
-                         , # Optional, but fallback too complex for here.
-                           # Inferred below instead.
-                           vendor ? assert false; null
-                         , kernel
-                         , # Also inferred below
-                           abi    ? assert false; null
-                         } @ args: let
-    getCpu    = name: cpuTypes.${name} or (throw "Unknown CPU type: ${name}");
-    getVendor = name:  vendors.${name} or (throw "Unknown vendor: ${name}");
-    getKernel = name:  kernels.${name} or (throw "Unknown kernel: ${name}");
-    getAbi    = name:     abis.${name} or (throw "Unknown ABI: ${name}");
-
-    parsed = rec {
-      cpu = getCpu args.cpu;
-      vendor =
-        /**/ if args ? vendor    then getVendor args.vendor
-        else if isDarwin  parsed then vendors.apple
-        else if isWindows parsed then vendors.pc
-        else                     vendors.unknown;
-      kernel = getKernel args.kernel;
-      abi =
-        /**/ if args ? abi       then getAbi args.abi
-        else if isLinux   parsed then abis.gnu
-        else if isWindows parsed then abis.gnu
-        else                     abis.unknown;
-    };
-
-  in mkSystem parsed;
-
-  mkSystemFromString = s: mkSystemFromSkeleton (mkSkeletonFromList (lib.splitString "-" s));
-
-  doubleFromSystem = { cpu, vendor, kernel, abi, ... }:
-    if abi == abis.cygnus
-    then "${cpu.name}-cygwin"
-    else "${cpu.name}-${kernel.name}";
-
-  tripleFromSystem = { cpu, vendor, kernel, abi, ... } @ sys: assert isSystem sys; let
-    optAbi = lib.optionalString (abi != abis.unknown) "-${abi.name}";
-  in "${cpu.name}-${vendor.name}-${kernel.name}${optAbi}";
-
-  ################################################################################
-
-}
--- a/lib/systems/platforms.nix
+++ b/lib/systems/platforms.nix
@@ -1,566 +0,0 @@
-{ lib }:
-rec {
-  pcBase = {
-    name = "pc";
-    kernelBaseConfig = "defconfig";
-    # Build whatever possible as a module, if not stated in the extra config.
-    kernelAutoModules = true;
-    kernelTarget = "bzImage";
-  };
-
-  pc64 = pcBase // { kernelArch = "x86_64"; };
-
-  pc32 = pcBase // { kernelArch = "i386"; };
-
-  pc32_simplekernel = pc32 // {
-    kernelAutoModules = false;
-  };
-
-  pc64_simplekernel = pc64 // {
-    kernelAutoModules = false;
-  };
-
-  pogoplug4 = {
-    name = "pogoplug4";
-
-    gcc = {
-      arch = "armv5te";
-      float = "soft";
-    };
-
-    kernelMajor = "2.6";
-    kernelBaseConfig = "multi_v5_defconfig";
-    kernelArch = "arm";
-    kernelAutoModules = false;
-    kernelExtraConfig =
-      ''
-        # Ubi for the mtd
-        MTD_UBI y
-        UBIFS_FS y
-        UBIFS_FS_XATTR y
-        UBIFS_FS_ADVANCED_COMPR y
-        UBIFS_FS_LZO y
-        UBIFS_FS_ZLIB y
-        UBIFS_FS_DEBUG n
-      '';
-    kernelMakeFlags = [ "LOADADDR=0x8000" ];
-    kernelTarget = "uImage";
-    # TODO reenable once manual-config's config actually builds a .dtb and this is checked to be working
-    #kernelDTB = true;
-  };
-
-  sheevaplug = {
-    name = "sheevaplug";
-    kernelMajor = "2.6";
-    kernelBaseConfig = "multi_v5_defconfig";
-    kernelArch = "arm";
-    kernelAutoModules = false;
-    kernelExtraConfig = ''
-      BLK_DEV_RAM y
-      BLK_DEV_INITRD y
-      BLK_DEV_CRYPTOLOOP m
-      BLK_DEV_DM m
-      DM_CRYPT m
-      MD y
-      REISERFS_FS m
-      BTRFS_FS m
-      XFS_FS m
-      JFS_FS m
-      EXT4_FS m
-      USB_STORAGE_CYPRESS_ATACB m
-
-      # mv cesa requires this sw fallback, for mv-sha1
-      CRYPTO_SHA1 y
-      # Fast crypto
-      CRYPTO_TWOFISH y
-      CRYPTO_TWOFISH_COMMON y
-      CRYPTO_BLOWFISH y
-      CRYPTO_BLOWFISH_COMMON y
-
-      IP_PNP y
-      IP_PNP_DHCP y
-      NFS_FS y
-      ROOT_NFS y
-      TUN m
-      NFS_V4 y
-      NFS_V4_1 y
-      NFS_FSCACHE y
-      NFSD m
-      NFSD_V2_ACL y
-      NFSD_V3 y
-      NFSD_V3_ACL y
-      NFSD_V4 y
-      NETFILTER y
-      IP_NF_IPTABLES y
-      IP_NF_FILTER y
-      IP_NF_MATCH_ADDRTYPE y
-      IP_NF_TARGET_LOG y
-      IP_NF_MANGLE y
-      IPV6 m
-      VLAN_8021Q m
-
-      CIFS y
-      CIFS_XATTR y
-      CIFS_POSIX y
-      CIFS_FSCACHE y
-      CIFS_ACL y
-
-      WATCHDOG y
-      WATCHDOG_CORE y
-      ORION_WATCHDOG m
-
-      ZRAM m
-      NETCONSOLE m
-
-      # Disable OABI to have seccomp_filter (required for systemd)
-      # https://github.com/raspberrypi/firmware/issues/651
-      OABI_COMPAT n
-
-      # Fail to build
-      DRM n
-      SCSI_ADVANSYS n
-      USB_ISP1362_HCD n
-      SND_SOC n
-      SND_ALI5451 n
-      FB_SAVAGE n
-      SCSI_NSP32 n
-      ATA_SFF n
-      SUNGEM n
-      IRDA n
-      ATM_HE n
-      SCSI_ACARD n
-      BLK_DEV_CMD640_ENHANCED n
-
-      FUSE_FS m
-
-      # systemd uses cgroups
-      CGROUPS y
-
-      # Latencytop
-      LATENCYTOP y
-
-      # Ubi for the mtd
-      MTD_UBI y
-      UBIFS_FS y
-      UBIFS_FS_XATTR y
-      UBIFS_FS_ADVANCED_COMPR y
-      UBIFS_FS_LZO y
-      UBIFS_FS_ZLIB y
-      UBIFS_FS_DEBUG n
-
-      # Kdb, for kernel troubles
-      KGDB y
-      KGDB_SERIAL_CONSOLE y
-      KGDB_KDB y
-    '';
-    kernelMakeFlags = [ "LOADADDR=0x0200000" ];
-    kernelTarget = "uImage";
-    kernelDTB = true; # Beyond 3.10
-    gcc = {
-      arch = "armv5te";
-      float = "soft";
-    };
-  };
-
-  raspberrypi = {
-    name = "raspberrypi";
-    kernelMajor = "2.6";
-    kernelBaseConfig = "bcmrpi_defconfig";
-    kernelDTB = true;
-    kernelArch = "arm";
-    kernelAutoModules = false;
-    kernelExtraConfig = ''
-      BLK_DEV_RAM y
-      BLK_DEV_INITRD y
-      BLK_DEV_CRYPTOLOOP m
-      BLK_DEV_DM m
-      DM_CRYPT m
-      MD y
-      REISERFS_FS m
-      BTRFS_FS y
-      XFS_FS m
-      JFS_FS y
-      EXT4_FS y
-
-      IP_PNP y
-      IP_PNP_DHCP y
-      NFS_FS y
-      ROOT_NFS y
-      TUN m
-      NFS_V4 y
-      NFS_V4_1 y
-      NFS_FSCACHE y
-      NFSD m
-      NFSD_V2_ACL y
-      NFSD_V3 y
-      NFSD_V3_ACL y
-      NFSD_V4 y
-      NETFILTER y
-      IP_NF_IPTABLES y
-      IP_NF_FILTER y
-      IP_NF_MATCH_ADDRTYPE y
-      IP_NF_TARGET_LOG y
-      IP_NF_MANGLE y
-      IPV6 m
-      VLAN_8021Q m
-
-      CIFS y
-      CIFS_XATTR y
-      CIFS_POSIX y
-      CIFS_FSCACHE y
-      CIFS_ACL y
-
-      ZRAM m
-
-      # Disable OABI to have seccomp_filter (required for systemd)
-      # https://github.com/raspberrypi/firmware/issues/651
-      OABI_COMPAT n
-
-      # Fail to build
-      DRM n
-      SCSI_ADVANSYS n
-      USB_ISP1362_HCD n
-      SND_SOC n
-      SND_ALI5451 n
-      FB_SAVAGE n
-      SCSI_NSP32 n
-      ATA_SFF n
-      SUNGEM n
-      IRDA n
-      ATM_HE n
-      SCSI_ACARD n
-      BLK_DEV_CMD640_ENHANCED n
-
-      FUSE_FS m
-
-      # nixos mounts some cgroup
-      CGROUPS y
-
-      # Latencytop
-      LATENCYTOP y
-    '';
-    kernelTarget = "zImage";
-    gcc = {
-      arch = "armv6";
-      fpu = "vfp";
-      float = "hard";
-      # TODO(@Ericson2314) what is this and is it a good idea? It was
-      # used in some cross compilation examples but not others.
-      #
-      # abi = "aapcs-linux";
-    };
-  };
-
-  raspberrypi2 = armv7l-hf-multiplatform // {
-    name = "raspberrypi2";
-    kernelBaseConfig = "bcm2709_defconfig";
-    kernelDTB = true;
-    kernelAutoModules = false;
-    kernelExtraConfig = ''
-      BLK_DEV_RAM y
-      BLK_DEV_INITRD y
-      BLK_DEV_CRYPTOLOOP m
-      BLK_DEV_DM m
-      DM_CRYPT m
-      MD y
-      REISERFS_FS m
-      BTRFS_FS y
-      XFS_FS m
-      JFS_FS y
-      EXT4_FS y
-
-      IP_PNP y
-      IP_PNP_DHCP y
-      NFS_FS y
-      ROOT_NFS y
-      TUN m
-      NFS_V4 y
-      NFS_V4_1 y
-      NFS_FSCACHE y
-      NFSD m
-      NFSD_V2_ACL y
-      NFSD_V3 y
-      NFSD_V3_ACL y
-      NFSD_V4 y
-      NETFILTER y
-      IP_NF_IPTABLES y
-      IP_NF_FILTER y
-      IP_NF_MATCH_ADDRTYPE y
-      IP_NF_TARGET_LOG y
-      IP_NF_MANGLE y
-      IPV6 m
-      VLAN_8021Q m
-
-      CIFS y
-      CIFS_XATTR y
-      CIFS_POSIX y
-      CIFS_FSCACHE y
-      CIFS_ACL y
-
-      ZRAM m
-
-      # Disable OABI to have seccomp_filter (required for systemd)
-      # https://github.com/raspberrypi/firmware/issues/651
-      OABI_COMPAT n
-
-      # Fail to build
-      DRM n
-      SCSI_ADVANSYS n
-      USB_ISP1362_HCD n
-      SND_SOC n
-      SND_ALI5451 n
-      FB_SAVAGE n
-      SCSI_NSP32 n
-      ATA_SFF n
-      SUNGEM n
-      IRDA n
-      ATM_HE n
-      SCSI_ACARD n
-      BLK_DEV_CMD640_ENHANCED n
-
-      FUSE_FS m
-
-      # nixos mounts some cgroup
-      CGROUPS y
-
-      # Latencytop
-      LATENCYTOP y
-
-      # Disable the common config Xen, it doesn't build on ARM
-      XEN? n
-    '';
-    kernelTarget = "zImage";
-  };
-
-  scaleway-c1 = armv7l-hf-multiplatform // {
-    gcc = {
-      cpu = "cortex-a9";
-      fpu = "vfpv3";
-      float = "hard";
-    };
-  };
-
-  utilite = {
-    name = "utilite";
-    kernelMajor = "2.6";
-    kernelBaseConfig = "multi_v7_defconfig";
-    kernelArch = "arm";
-    kernelAutoModules = false;
-    kernelExtraConfig =
-      ''
-        # Ubi for the mtd
-        MTD_UBI y
-        UBIFS_FS y
-        UBIFS_FS_XATTR y
-        UBIFS_FS_ADVANCED_COMPR y
-        UBIFS_FS_LZO y
-        UBIFS_FS_ZLIB y
-        UBIFS_FS_DEBUG n
-      '';
-    kernelMakeFlags = [ "LOADADDR=0x10800000" ];
-    kernelTarget = "uImage";
-    kernelDTB = true;
-    gcc = {
-      cpu = "cortex-a9";
-      fpu = "neon";
-      float = "hard";
-    };
-  };
-
-  guruplug = sheevaplug // {
-    # Define `CONFIG_MACH_GURUPLUG' (see
-    # <http://kerneltrap.org/mailarchive/git-commits-head/2010/5/19/33618>)
-    # and other GuruPlug-specific things.  Requires the `guruplug-defconfig'
-    # patch.
-
-    kernelBaseConfig = "guruplug_defconfig";
-  };
-
-  fuloong2f_n32 = {
-    name = "fuloong2f_n32";
-    kernelMajor = "2.6";
-    kernelBaseConfig = "lemote2f_defconfig";
-    kernelArch = "mips";
-    kernelAutoModules = false;
-    kernelExtraConfig = ''
-      MIGRATION n
-      COMPACTION n
-
-      # nixos mounts some cgroup
-      CGROUPS y
-
-      BLK_DEV_RAM y
-      BLK_DEV_INITRD y
-      BLK_DEV_CRYPTOLOOP m
-      BLK_DEV_DM m
-      DM_CRYPT m
-      MD y
-      REISERFS_FS m
-      EXT4_FS m
-      USB_STORAGE_CYPRESS_ATACB m
-
-      IP_PNP y
-      IP_PNP_DHCP y
-      IP_PNP_BOOTP y
-      NFS_FS y
-      ROOT_NFS y
-      TUN m
-      NFS_V4 y
-      NFS_V4_1 y
-      NFS_FSCACHE y
-      NFSD m
-      NFSD_V2_ACL y
-      NFSD_V3 y
-      NFSD_V3_ACL y
-      NFSD_V4 y
-
-      # Fail to build
-      DRM n
-      SCSI_ADVANSYS n
-      USB_ISP1362_HCD n
-      SND_SOC n
-      SND_ALI5451 n
-      FB_SAVAGE n
-      SCSI_NSP32 n
-      ATA_SFF n
-      SUNGEM n
-      IRDA n
-      ATM_HE n
-      SCSI_ACARD n
-      BLK_DEV_CMD640_ENHANCED n
-
-      FUSE_FS m
-
-      # Needed for udev >= 150
-      SYSFS_DEPRECATED_V2 n
-
-      VGA_CONSOLE n
-      VT_HW_CONSOLE_BINDING y
-      SERIAL_8250_CONSOLE y
-      FRAMEBUFFER_CONSOLE y
-      EXT2_FS y
-      EXT3_FS y
-      REISERFS_FS y
-      MAGIC_SYSRQ y
-
-      # The kernel doesn't boot at all, with FTRACE
-      FTRACE n
-    '';
-    kernelTarget = "vmlinux";
-    gcc = {
-      arch = "loongson2f";
-      abi = "n32";
-    };
-  };
-
-  beaglebone = armv7l-hf-multiplatform // {
-    name = "beaglebone";
-    kernelBaseConfig = "bb.org_defconfig";
-    kernelAutoModules = false;
-    kernelExtraConfig = ""; # TBD kernel config
-    kernelTarget = "zImage";
-  };
-
-  armv7l-hf-multiplatform = {
-    name = "armv7l-hf-multiplatform";
-    kernelMajor = "2.6"; # Using "2.6" enables 2.6 kernel syscalls in glibc.
-    kernelBaseConfig = "multi_v7_defconfig";
-    kernelArch = "arm";
-    kernelDTB = true;
-    kernelAutoModules = true;
-    kernelPreferBuiltin = true;
-    kernelTarget = "zImage";
-    kernelExtraConfig = ''
-      # Serial port for Raspberry Pi 3. Upstream forgot to add it to the ARMv7 defconfig.
-      SERIAL_8250_BCM2835AUX y
-      SERIAL_8250_EXTENDED y
-      SERIAL_8250_SHARE_IRQ y
-
-      # Fix broken sunxi-sid nvmem driver.
-      TI_CPTS y
-
-      # Hangs ODROID-XU4
-      ARM_BIG_LITTLE_CPUIDLE n
-    '';
-    gcc = {
-      # Some table about fpu flags:
-      # http://community.arm.com/servlet/JiveServlet/showImage/38-1981-3827/blogentry-103749-004812900+1365712953_thumb.png
-      # Cortex-A5: -mfpu=neon-fp16
-      # Cortex-A7 (rpi2): -mfpu=neon-vfpv4
-      # Cortex-A8 (beaglebone): -mfpu=neon
-      # Cortex-A9: -mfpu=neon-fp16
-      # Cortex-A15: -mfpu=neon-vfpv4
-
-      # More about FPU:
-      # https://wiki.debian.org/ArmHardFloatPort/VfpComparison
-
-      # vfpv3-d16 is what Debian uses and seems to be the best compromise: NEON is not supported in e.g. Scaleway or Tegra 2,
-      # and the above page suggests NEON is only an improvement with hand-written assembly.
-      arch = "armv7-a";
-      fpu = "vfpv3-d16";
-      float = "hard";
-
-      # For Raspberry Pi the 2 the best would be:
-      #   cpu = "cortex-a7";
-      #   fpu = "neon-vfpv4";
-    };
-  };
-
-  aarch64-multiplatform = {
-    name = "aarch64-multiplatform";
-    kernelMajor = "2.6"; # Using "2.6" enables 2.6 kernel syscalls in glibc.
-    kernelBaseConfig = "defconfig";
-    kernelArch = "arm64";
-    kernelDTB = true;
-    kernelAutoModules = true;
-    kernelPreferBuiltin = true;
-    kernelExtraConfig = ''
-      # Raspberry Pi 3 stuff. Not needed for kernels >= 4.10.
-      ARCH_BCM2835 y
-      BCM2835_MBOX y
-      BCM2835_WDT y
-      RASPBERRYPI_FIRMWARE y
-      RASPBERRYPI_POWER y
-      SERIAL_8250_BCM2835AUX y
-      SERIAL_8250_EXTENDED y
-      SERIAL_8250_SHARE_IRQ y
-
-      # Cavium ThunderX stuff.
-      PCI_HOST_THUNDER_ECAM y
-
-      # Nvidia Tegra stuff.
-      PCI_TEGRA y
-
-      # The default (=y) forces us to have the XHCI firmware available in initrd,
-      # which our initrd builder can't currently do easily.
-      USB_XHCI_TEGRA m
-    '';
-    kernelTarget = "Image";
-    gcc = {
-      arch = "armv8-a";
-    };
-  };
-
-  riscv-multiplatform = bits: {
-    name = "riscv-multiplatform";
-    kernelArch = "riscv";
-    bfdEmulation = "elf${bits}lriscv";
-    kernelTarget = "vmlinux";
-    kernelAutoModules = true;
-    kernelBaseConfig = "defconfig";
-    kernelExtraConfig = ''
-      FTRACE n
-      SERIAL_OF_PLATFORM y
-    '';
-  };
-
-  selectBySystem = system: {
-      "i686-linux" = pc32;
-      "x86_64-linux" = pc64;
-      "armv5tel-linux" = sheevaplug;
-      "armv6l-linux" = raspberrypi;
-      "armv7l-linux" = armv7l-hf-multiplatform;
-      "aarch64-linux" = aarch64-multiplatform;
-      "mipsel-linux" = fuloong2f_n32;
-    }.${system} or pcBase;
-}
--- a/lib/tests.nix
+++ b/lib/tests.nix
@@ -0,0 +1,223 @@
+let inherit (builtins) add; in
+with import ./default.nix;
+
+runTests {
+
+  testId = {
+    expr = id 1;
+    expected = 1;
+  };
+
+  testConst = {
+    expr = const 2 3;
+    expected = 2;
+  };
+
+  /*
+  testOr = {
+    expr = or true false;
+    expected = true;
+  };
+  */
+
+  testAnd = {
+    expr = and true false;
+    expected = false;
+  };
+
+  testFix = {
+    expr = fix (x: {a = if x ? a then "a" else "b";});
+    expected = {a = "a";};
+  };
+
+  testConcatMapStrings = {
+    expr = concatMapStrings (x: x + ";") ["a" "b" "c"];
+    expected = "a;b;c;";
+  };
+
+  testConcatStringsSep = {
+    expr = concatStringsSep "," ["a" "b" "c"];
+    expected = "a,b,c";
+  };
+
+  testFilter = {
+    expr = filter (x: x != "a") ["a" "b" "c" "a"];
+    expected = ["b" "c"];
+  };
+
+  testFold = {
+    expr = fold (builtins.add) 0 (range 0 100);
+    expected = 5050;
+  };
+
+  testTake = testAllTrue [
+    ([] == (take 0 [  1 2 3 ]))
+    ([1] == (take 1 [  1 2 3 ]))
+    ([ 1 2 ] == (take 2 [  1 2 3 ]))
+    ([ 1 2 3 ] == (take 3 [  1 2 3 ]))
+    ([ 1 2 3 ] == (take 4 [  1 2 3 ]))
+  ];
+
+  testFoldAttrs = {
+    expr = foldAttrs (n: a: [n] ++ a) [] [
+    { a = 2; b = 7; }
+    { a = 3;        c = 8; }
+    ];
+    expected = { a = [ 2 3 ]; b = [7]; c = [8];};
+  };
+
+  testOverridableDelayableArgsTest = {
+    expr =
+      let res1 = defaultOverridableDelayableArgs id {};
+          res2 = defaultOverridableDelayableArgs id { a = 7; };
+          res3 = let x = defaultOverridableDelayableArgs id { a = 7; };
+                 in (x.merge) { b = 10; };
+          res4 = let x = defaultOverridableDelayableArgs id { a = 7; };
+                in (x.merge) ( x: { b = 10; });
+          res5 = let x = defaultOverridableDelayableArgs id { a = 7; };
+                in (x.merge) ( x: { a = add x.a 3; });
+          res6 = let x = defaultOverridableDelayableArgs id { a = 7; mergeAttrBy = { a = add; }; };
+                     y = x.merge {};
+                in (y.merge) { a = 10; };
+
+          resRem7 = res6.replace (a : removeAttrs a ["a"]);
+
+          resReplace6 = let x = defaultOverridableDelayableArgs id { a = 7; mergeAttrBy = { a = add; }; };
+                            x2 = x.merge { a = 20; }; # now we have 27
+                        in (x2.replace) { a = 10; }; # and override the value by 10
+
+          # fixed tests (delayed args): (when using them add some comments, please)
+          resFixed1 =
+                let x = defaultOverridableDelayableArgs id ( x : { a = 7; c = x.fixed.b; });
+                    y = x.merge (x : { name = "name-${builtins.toString x.fixed.c}"; });
+                in (y.merge) { b = 10; };
+          strip = attrs : removeAttrs attrs ["merge" "replace"];
+      in all id
+        [ ((strip res1) == { })
+          ((strip res2) == { a = 7; })
+          ((strip res3) == { a = 7; b = 10; })
+          ((strip res4) == { a = 7; b = 10; })
+          ((strip res5) == { a = 10; })
+          ((strip res6) == { a = 17; })
+          ((strip resRem7) == {})
+          ((strip resFixed1) == { a = 7; b = 10; c =10; name = "name-10"; })
+        ];
+    expected = true;
+  };
+
+  testSort = {
+    expr = sort builtins.lessThan [ 40 2 30 42 ];
+    expected = [2 30 40 42];
+  };
+
+  testToIntShouldConvertStringToInt = {
+    expr = toInt "27";
+    expected = 27;
+  };
+
+  testToIntShouldThrowErrorIfItCouldNotConvertToInt = {
+    expr = builtins.tryEval (toInt "\"foo\"");
+    expected = { success = false; value = false; };
+  };
+
+  testHasAttrByPathTrue = {
+    expr = hasAttrByPath ["a" "b"] { a = { b = "yey"; }; };
+    expected = true;
+  };
+
+  testHasAttrByPathFalse = {
+    expr = hasAttrByPath ["a" "b"] { a = { c = "yey"; }; };
+    expected = false;
+  };
+
+
+  /* Generator tests */
+  # these tests assume attributes are converted to lists
+  # in alphabetical order
+
+  testMkKeyValueDefault = {
+    expr = generators.mkKeyValueDefault ":" "f:oo" "bar";
+    expected = ''f\:oo:bar'';
+  };
+
+  testToKeyValue = {
+    expr = generators.toKeyValue {} {
+      key = "value";
+      "other=key" = "baz";
+    };
+    expected = ''
+      key=value
+      other\=key=baz
+    '';
+  };
+
+  testToINIEmpty = {
+    expr = generators.toINI {} {};
+    expected = "";
+  };
+
+  testToINIEmptySection = {
+    expr = generators.toINI {} { foo = {}; bar = {}; };
+    expected = ''
+      [bar]
+
+      [foo]
+    '';
+  };
+
+  testToINIDefaultEscapes = {
+    expr = generators.toINI {} {
+      "no [ and ] allowed unescaped" = {
+        "and also no = in keys" = 42;
+      };
+    };
+    expected = ''
+      [no \[ and \] allowed unescaped]
+      and also no \= in keys=42
+    '';
+  };
+
+  testToINIDefaultFull = {
+    expr = generators.toINI {} {
+      "section 1" = {
+        attribute1 = 5;
+        x = "Me-se JarJar Binx";
+      };
+      "foo[]" = {
+        "he\\h=he" = "this is okay";
+      };
+    };
+    expected = ''
+      [foo\[\]]
+      he\h\=he=this is okay
+
+      [section 1]
+      attribute1=5
+      x=Me-se JarJar Binx
+    '';
+  };
+
+  /* right now only invocation check */
+  testToJSONSimple =
+    let val = {
+      foobar = [ "baz" 1 2 3 ];
+    };
+    in {
+      expr = generators.toJSON {} val;
+      # trival implementation
+      expected = builtins.toJSON val;
+  };
+
+  /* right now only invocation check */
+  testToYAMLSimple =
+    let val = {
+      list = [ { one = 1; } { two = 2; } ];
+      all = 42;
+    };
+    in {
+      expr = generators.toYAML {} val;
+      # trival implementation
+      expected = builtins.toJSON val;
+  };
+
+}
--- a/lib/tests/misc.nix
+++ b/lib/tests/misc.nix
@@ -1,361 +0,0 @@
-# to run these tests:
-# nix-instantiate --eval --strict nixpkgs/lib/tests/misc.nix
-# if the resulting list is empty, all tests passed
-with import ../default.nix;
-
-runTests {
-
-
-# TRIVIAL
-
-  testId = {
-    expr = id 1;
-    expected = 1;
-  };
-
-  testConst = {
-    expr = const 2 3;
-    expected = 2;
-  };
-
-  /*
-  testOr = {
-    expr = or true false;
-    expected = true;
-  };
-  */
-
-  testAnd = {
-    expr = and true false;
-    expected = false;
-  };
-
-  testFix = {
-    expr = fix (x: {a = if x ? a then "a" else "b";});
-    expected = {a = "a";};
-  };
-
-  testComposeExtensions = {
-    expr = let obj = makeExtensible (self: { foo = self.bar; });
-               f = self: super: { bar = false; baz = true; };
-               g = self: super: { bar = super.baz or false; };
-               f_o_g = composeExtensions f g;
-               composed = obj.extend f_o_g;
-           in composed.foo;
-    expected = true;
-  };
-
-# STRINGS
-
-  testConcatMapStrings = {
-    expr = concatMapStrings (x: x + ";") ["a" "b" "c"];
-    expected = "a;b;c;";
-  };
-
-  testConcatStringsSep = {
-    expr = concatStringsSep "," ["a" "b" "c"];
-    expected = "a,b,c";
-  };
-
-  testSplitStringsSimple = {
-    expr = strings.splitString "." "a.b.c.d";
-    expected = [ "a" "b" "c" "d" ];
-  };
-
-  testSplitStringsEmpty = {
-    expr = strings.splitString "." "a..b";
-    expected = [ "a" "" "b" ];
-  };
-
-  testSplitStringsOne = {
-    expr = strings.splitString ":" "a.b";
-    expected = [ "a.b" ];
-  };
-
-  testSplitStringsNone = {
-    expr = strings.splitString "." "";
-    expected = [ "" ];
-  };
-
-  testSplitStringsFirstEmpty = {
-    expr = strings.splitString "/" "/a/b/c";
-    expected = [ "" "a" "b" "c" ];
-  };
-
-  testSplitStringsLastEmpty = {
-    expr = strings.splitString ":" "2001:db8:0:0042::8a2e:370:";
-    expected = [ "2001" "db8" "0" "0042" "" "8a2e" "370" "" ];
-  };
-
-  testIsStorePath =  {
-    expr =
-      let goodPath =
-            "${builtins.storeDir}/d945ibfx9x185xf04b890y4f9g3cbb63-python-2.7.11";
-      in {
-        storePath = isStorePath goodPath;
-        storePathAppendix = isStorePath
-          "${goodPath}/bin/python";
-        nonAbsolute = isStorePath (concatStrings (tail (stringToCharacters goodPath)));
-        asPath = isStorePath (builtins.toPath goodPath);
-        otherPath = isStorePath "/something/else";
-        otherVals = {
-          attrset = isStorePath {};
-          list = isStorePath [];
-          int = isStorePath 42;
-        };
-      };
-    expected = {
-      storePath = true;
-      storePathAppendix = false;
-      nonAbsolute = false;
-      asPath = true;
-      otherPath = false;
-      otherVals = {
-        attrset = false;
-        list = false;
-        int = false;
-      };
-    };
-  };
-
-# LISTS
-
-  testFilter = {
-    expr = filter (x: x != "a") ["a" "b" "c" "a"];
-    expected = ["b" "c"];
-  };
-
-  testFold =
-    let
-      f = op: fold: fold op 0 (range 0 100);
-      # fold with associative operator
-      assoc = f builtins.add;
-      # fold with non-associative operator
-      nonAssoc = f builtins.sub;
-    in {
-      expr = {
-        assocRight = assoc foldr;
-        # right fold with assoc operator is same as left fold
-        assocRightIsLeft = assoc foldr == assoc foldl;
-        nonAssocRight = nonAssoc foldr;
-        nonAssocLeft = nonAssoc foldl;
-        # with non-assoc operator the fold results are not the same
-        nonAssocRightIsNotLeft = nonAssoc foldl != nonAssoc foldr;
-        # fold is an alias for foldr
-        foldIsRight = nonAssoc fold == nonAssoc foldr;
-      };
-      expected = {
-        assocRight = 5050;
-        assocRightIsLeft = true;
-        nonAssocRight = 50;
-        nonAssocLeft = (-5050);
-        nonAssocRightIsNotLeft = true;
-        foldIsRight = true;
-      };
-    };
-
-  testTake = testAllTrue [
-    ([] == (take 0 [  1 2 3 ]))
-    ([1] == (take 1 [  1 2 3 ]))
-    ([ 1 2 ] == (take 2 [  1 2 3 ]))
-    ([ 1 2 3 ] == (take 3 [  1 2 3 ]))
-    ([ 1 2 3 ] == (take 4 [  1 2 3 ]))
-  ];
-
-  testFoldAttrs = {
-    expr = foldAttrs (n: a: [n] ++ a) [] [
-    { a = 2; b = 7; }
-    { a = 3;        c = 8; }
-    ];
-    expected = { a = [ 2 3 ]; b = [7]; c = [8];};
-  };
-
-  testSort = {
-    expr = sort builtins.lessThan [ 40 2 30 42 ];
-    expected = [2 30 40 42];
-  };
-
-  testToIntShouldConvertStringToInt = {
-    expr = toInt "27";
-    expected = 27;
-  };
-
-  testToIntShouldThrowErrorIfItCouldNotConvertToInt = {
-    expr = builtins.tryEval (toInt "\"foo\"");
-    expected = { success = false; value = false; };
-  };
-
-  testHasAttrByPathTrue = {
-    expr = hasAttrByPath ["a" "b"] { a = { b = "yey"; }; };
-    expected = true;
-  };
-
-  testHasAttrByPathFalse = {
-    expr = hasAttrByPath ["a" "b"] { a = { c = "yey"; }; };
-    expected = false;
-  };
-
-
-# GENERATORS
-# these tests assume attributes are converted to lists
-# in alphabetical order
-
-  testMkKeyValueDefault = {
-    expr = generators.mkKeyValueDefault {} ":" "f:oo" "bar";
-    expected = ''f\:oo:bar'';
-  };
-
-  testToKeyValue = {
-    expr = generators.toKeyValue {} {
-      key = "value";
-      "other=key" = "baz";
-    };
-    expected = ''
-      key=value
-      other\=key=baz
-    '';
-  };
-
-  testToINIEmpty = {
-    expr = generators.toINI {} {};
-    expected = "";
-  };
-
-  testToINIEmptySection = {
-    expr = generators.toINI {} { foo = {}; bar = {}; };
-    expected = ''
-      [bar]
-
-      [foo]
-    '';
-  };
-
-  testToINIDefaultEscapes = {
-    expr = generators.toINI {} {
-      "no [ and ] allowed unescaped" = {
-        "and also no = in keys" = 42;
-      };
-    };
-    expected = ''
-      [no \[ and \] allowed unescaped]
-      and also no \= in keys=42
-    '';
-  };
-
-  testToINIDefaultFull = {
-    expr = generators.toINI {} {
-      "section 1" = {
-        attribute1 = 5;
-        x = "Me-se JarJar Binx";
-      };
-      "foo[]" = {
-        "he\\h=he" = "this is okay";
-      };
-    };
-    expected = ''
-      [foo\[\]]
-      he\h\=he=this is okay
-
-      [section 1]
-      attribute1=5
-      x=Me-se JarJar Binx
-    '';
-  };
-
-  /* right now only invocation check */
-  testToJSONSimple =
-    let val = {
-      foobar = [ "baz" 1 2 3 ];
-    };
-    in {
-      expr = generators.toJSON {} val;
-      # trivial implementation
-      expected = builtins.toJSON val;
-  };
-
-  /* right now only invocation check */
-  testToYAMLSimple =
-    let val = {
-      list = [ { one = 1; } { two = 2; } ];
-      all = 42;
-    };
-    in {
-      expr = generators.toYAML {} val;
-      # trivial implementation
-      expected = builtins.toJSON val;
-  };
-
-  testToPretty = {
-    expr = mapAttrs (const (generators.toPretty {})) rec {
-      int = 42;
-      bool = true;
-      string = "fnord";
-      null_ = null;
-      function = x: x;
-      functionArgs = { arg ? 4, foo }: arg;
-      list = [ 3 4 function [ false ] ];
-      attrs = { foo = null; "foo bar" = "baz"; };
-      drv = derivation { name = "test"; system = builtins.currentSystem; };
-    };
-    expected = rec {
-      int = "42";
-      bool = "true";
-      string = "\"fnord\"";
-      null_ = "null";
-      function = "<λ>";
-      functionArgs = "<λ:{(arg),foo}>";
-      list = "[ 3 4 ${function} [ false ] ]";
-      attrs = "{ \"foo\" = null; \"foo bar\" = \"baz\"; }";
-      drv = "<δ>";
-    };
-  };
-
-  testToPrettyAllowPrettyValues = {
-    expr = generators.toPretty { allowPrettyValues = true; }
-             { __pretty = v: "«" + v + "»"; val = "foo"; };
-    expected  = "«foo»";
-  };
-
-
-# MISC
-
-  testOverridableDelayableArgsTest = {
-    expr =
-      let res1 = defaultOverridableDelayableArgs id {};
-          res2 = defaultOverridableDelayableArgs id { a = 7; };
-          res3 = let x = defaultOverridableDelayableArgs id { a = 7; };
-                 in (x.merge) { b = 10; };
-          res4 = let x = defaultOverridableDelayableArgs id { a = 7; };
-                in (x.merge) ( x: { b = 10; });
-          res5 = let x = defaultOverridableDelayableArgs id { a = 7; };
-                in (x.merge) ( x: { a = builtins.add x.a 3; });
-          res6 = let x = defaultOverridableDelayableArgs id { a = 7; mergeAttrBy = { a = builtins.add; }; };
-                     y = x.merge {};
-                in (y.merge) { a = 10; };
-
-          resRem7 = res6.replace (a: removeAttrs a ["a"]);
-
-          resReplace6 = let x = defaultOverridableDelayableArgs id { a = 7; mergeAttrBy = { a = builtins.add; }; };
-                            x2 = x.merge { a = 20; }; # now we have 27
-                        in (x2.replace) { a = 10; }; # and override the value by 10
-
-          # fixed tests (delayed args): (when using them add some comments, please)
-          resFixed1 =
-                let x = defaultOverridableDelayableArgs id ( x: { a = 7; c = x.fixed.b; });
-                    y = x.merge (x: { name = "name-${builtins.toString x.fixed.c}"; });
-                in (y.merge) { b = 10; };
-          strip = attrs: removeAttrs attrs ["merge" "replace"];
-      in all id
-        [ ((strip res1) == { })
-          ((strip res2) == { a = 7; })
-          ((strip res3) == { a = 7; b = 10; })
-          ((strip res4) == { a = 7; b = 10; })
-          ((strip res5) == { a = 10; })
-          ((strip res6) == { a = 17; })
-          ((strip resRem7) == {})
-          ((strip resFixed1) == { a = 7; b = 10; c =10; name = "name-10"; })
-        ];
-    expected = true;
-  };
-
-}
--- a/lib/tests/modules.sh
+++ b/lib/tests/modules.sh
@@ -61,16 +61,6 @@ checkConfigError() {
 checkConfigOutput "false" config.enable ./declare-enable.nix
 checkConfigError 'The option .* defined in .* does not exist.' config.enable ./define-enable.nix

-# Check integer types.
-# unsigned
-checkConfigOutput "42" config.value ./declare-int-unsigned-value.nix ./define-value-int-positive.nix
-checkConfigError 'The option value .* in .* is not of type.*unsigned integer.*' config.value ./declare-int-unsigned-value.nix ./define-value-int-negative.nix
-# positive
-checkConfigError 'The option value .* in .* is not of type.*positive integer.*' config.value ./declare-int-positive-value.nix ./define-value-int-zero.nix
-# between
-checkConfigOutput "42" config.value ./declare-int-between-value.nix ./define-value-int-positive.nix
-checkConfigError 'The option value .* in .* is not of type.*between.*-21 and 43.*inclusive.*' config.value ./declare-int-between-value.nix ./define-value-int-negative.nix
-
 # Check mkForce without submodules.
 set -- config.enable ./declare-enable.nix ./define-enable.nix
 checkConfigOutput "true" "$@"
@@ -109,14 +99,6 @@ checkConfigOutput 'true' "$@" ./define-enable.nix ./define-loaOfSub-if-foo-enabl
 checkConfigOutput 'true' "$@" ./define-enable.nix ./define-loaOfSub-foo-if-enable.nix
 checkConfigOutput 'true' "$@" ./define-enable.nix ./define-loaOfSub-foo-enable-if.nix

-# Check disabledModules with config definitions and option declarations.
-set -- config.enable ./define-enable.nix ./declare-enable.nix
-checkConfigOutput "true" "$@"
-checkConfigOutput "false" "$@" ./disable-define-enable.nix
-checkConfigError "The option .*enable.* defined in .* does not exist" "$@" ./disable-declare-enable.nix
-checkConfigError "attribute .*enable.* in selection path .*config.enable.* not found" "$@" ./disable-define-enable.nix ./disable-declare-enable.nix
-checkConfigError "attribute .*enable.* in selection path .*config.enable.* not found" "$@" ./disable-enable-modules.nix
-
 # Check _module.args.
 set -- config.enable ./declare-enable.nix ./define-enable-with-custom-arg.nix
 checkConfigError 'while evaluating the module argument .*custom.* in .*define-enable-with-custom-arg.nix.*:' "$@"
@@ -136,7 +118,7 @@ checkConfigOutput "true" "$@" ./define-module-check.nix
 # Check coerced value.
 checkConfigOutput "\"42\"" config.value ./declare-coerced-value.nix
 checkConfigOutput "\"24\"" config.value ./declare-coerced-value.nix ./define-value-string.nix
-checkConfigError 'The option value .* in .* is not.*string or signed integer.*' config.value ./declare-coerced-value.nix ./define-value-list.nix
+checkConfigError 'The option value .* in .* is not a string or integer.' config.value ./declare-coerced-value.nix ./define-value-list.nix

 cat <<EOF
 ====== module tests ======
--- a/lib/tests/modules/declare-int-between-value.nix
+++ b/lib/tests/modules/declare-int-between-value.nix
@@ -1,9 +0,0 @@
-{ lib, ... }:
-
-{
-  options = {
-    value = lib.mkOption {
-      type = lib.types.ints.between (-21) 43;
-    };
-  };
-}
--- a/lib/tests/modules/declare-int-positive-value.nix
+++ b/lib/tests/modules/declare-int-positive-value.nix
@@ -1,9 +0,0 @@
-{ lib, ... }:
-
-{
-  options = {
-    value = lib.mkOption {
-      type = lib.types.ints.positive;
-    };
-  };
-}
--- a/lib/tests/modules/declare-int-unsigned-value.nix
+++ b/lib/tests/modules/declare-int-unsigned-value.nix
@@ -1,9 +0,0 @@
-{ lib, ... }:
-
-{
-  options = {
-    value = lib.mkOption {
-      type = lib.types.ints.unsigned;
-    };
-  };
-}
--- a/lib/tests/modules/default.nix
+++ b/lib/tests/modules/default.nix
@@ -1,8 +1,7 @@
-{ lib ? import ../.., modules ? [] }:
+{ lib ? import <nixpkgs/lib>, modules ? [] }:

 {
  inherit (lib.evalModules {
    inherit modules;
-    specialArgs.modulesPath = ./.;
  }) config options;
 }
--- a/lib/tests/modules/define-value-int-negative.nix
+++ b/lib/tests/modules/define-value-int-negative.nix
@@ -1,3 +0,0 @@
-{
-  value = -23;
-}
--- a/lib/tests/modules/define-value-int-positive.nix
+++ b/lib/tests/modules/define-value-int-positive.nix
@@ -1,3 +0,0 @@
-{
-  value = 42;
-}
--- a/lib/tests/modules/define-value-int-zero.nix
+++ b/lib/tests/modules/define-value-int-zero.nix
@@ -1,3 +0,0 @@
-{
-  value = 0;
-}
--- a/lib/tests/modules/disable-declare-enable.nix
+++ b/lib/tests/modules/disable-declare-enable.nix
@@ -1,5 +0,0 @@
-{ lib, ... }:
-
-{
-  disabledModules = [ ./declare-enable.nix ];
-}
--- a/lib/tests/modules/disable-define-enable.nix
+++ b/lib/tests/modules/disable-define-enable.nix
@@ -1,5 +0,0 @@
-{ lib, ... }:
-
-{
-  disabledModules = [ ./define-enable.nix ];
-}
--- a/lib/tests/modules/disable-enable-modules.nix
+++ b/lib/tests/modules/disable-enable-modules.nix
@@ -1,5 +0,0 @@
-{ lib, ... }:
-
-{
-  disabledModules = [ "define-enable.nix" "declare-enable.nix" ];
-}
--- a/lib/tests/release.nix
+++ b/lib/tests/release.nix
@@ -1,12 +1,15 @@
-{ pkgs ? import ((import ../.).cleanSource ../..) {} }:
+{ nixpkgs }:

-pkgs.stdenv.mkDerivation {
+with import ../.. { };
+with lib;
+
+stdenv.mkDerivation {
  name = "nixpkgs-lib-tests";
-  buildInputs = [ pkgs.nix ];
-  NIX_PATH="nixpkgs=${pkgs.path}";
+  buildInputs = [ nix ];
+  NIX_PATH="nixpkgs=${nixpkgs}";

  buildCommand = ''
-    datadir="${pkgs.nix}/share"
+    datadir="${nix}/share"
    export TEST_ROOT=$(pwd)/test-tmp
    export NIX_BUILD_HOOK=
    export NIX_CONF_DIR=$TEST_ROOT/etc
@@ -20,13 +23,9 @@ pkgs.stdenv.mkDerivation {
    cacheDir=$TEST_ROOT/binary-cache
    nix-store --init

-    cd ${pkgs.path}/lib/tests
+    cd ${nixpkgs}/lib/tests
    ./modules.sh

-    [[ "$(nix-instantiate --eval --strict misc.nix)" == "[ ]" ]]
-
-    [[ "$(nix-instantiate --eval --strict systems.nix)" == "[ ]" ]]
-
    touch $out
  '';
 }
--- a/lib/tests/systems.nix
+++ b/lib/tests/systems.nix
@@ -1,31 +0,0 @@
-# We assert that the new algorithmic way of generating these lists matches the
-# way they were hard-coded before.
-#
-# One might think "if we exhaustively test, what's the point of procedurally
-# calculating the lists anyway?". The answer is one can mindlessly update these
-# tests as new platforms become supported, and then just give the diff a quick
-# sanity check before committing :).
-let
-  lib = import ../default.nix;
-  mseteq = x: y: {
-    expr     = lib.sort lib.lessThan x;
-    expected = lib.sort lib.lessThan y;
-  };
-in with lib.systems.doubles; lib.runTests {
-  all = assertTrue (mseteq all (linux ++ darwin ++ cygwin ++ freebsd ++ openbsd ++ netbsd ++ illumos));
-
-  arm = assertTrue (mseteq arm [ "armv5tel-linux" "armv6l-linux" "armv7l-linux" ]);
-  i686 = assertTrue (mseteq i686 [ "i686-linux" "i686-freebsd" "i686-netbsd" "i686-openbsd" "i686-cygwin" ]);
-  mips = assertTrue (mseteq mips [ "mipsel-linux" ]);
-  x86_64 = assertTrue (mseteq x86_64 [ "x86_64-linux" "x86_64-darwin" "x86_64-freebsd" "x86_64-openbsd" "x86_64-netbsd" "x86_64-cygwin" "x86_64-solaris" ]);
-
-  cygwin = assertTrue (mseteq cygwin [ "i686-cygwin" "x86_64-cygwin" ]);
-  darwin = assertTrue (mseteq darwin [ "x86_64-darwin" ]);
-  freebsd = assertTrue (mseteq freebsd [ "i686-freebsd" "x86_64-freebsd" ]);
-  gnu = assertTrue (mseteq gnu (linux /* ++ hurd ++ kfreebsd ++ ... */));
-  illumos = assertTrue (mseteq illumos [ "x86_64-solaris" ]);
-  linux = assertTrue (mseteq linux [ "i686-linux" "x86_64-linux" "armv5tel-linux" "armv6l-linux" "armv7l-linux" "aarch64-linux" "mipsel-linux" ]);
-  netbsd = assertTrue (mseteq netbsd [ "i686-netbsd" "x86_64-netbsd" ]);
-  openbsd = assertTrue (mseteq openbsd [ "i686-openbsd" "x86_64-openbsd" ]);
-  unix = assertTrue (mseteq unix (linux ++ darwin ++ freebsd ++ openbsd ++ netbsd ++ illumos));
-}
--- a/lib/trivial.nix
+++ b/lib/trivial.nix
@@ -1,62 +1,93 @@
-{ lib }:
 rec {

-  /* The identity function
-     For when you need a function that does “nothing”.
-
-     Type: id :: a -> a
-  */
+  # Identity function.
  id = x: x;

-  /* The constant function
-     Ignores the second argument.
-     Or: Construct a function that always returns a static value.
-
-     Type: const :: a -> b -> a
-     Example:
-       let f = const 5; in f 10
-       => 5
-  */
+  # Constant function.
  const = x: y: x;

-
-  ## Named versions corresponding to some builtin operators.
-
-  /* Concat two strings */
+  # Named versions corresponding to some builtin operators.
  concat = x: y: x ++ y;
-
-  /* boolean “or” */
  or = x: y: x || y;
-
-  /* boolean “and” */
  and = x: y: x && y;
-
-  /* Convert a boolean to a string.
-     Note that toString on a bool returns "1" and "".
-  */
-  boolToString = b: if b then "true" else "false";
-
-  /* Merge two attribute sets shallowly, right side trumps left
-
-     Example:
-       mergeAttrs { a = 1; b = 2; } { b = 3; c = 4; }
-       => { a = 1; b = 3; c = 4; }
-  */
  mergeAttrs = x: y: x // y;

+  # Compute the fixed point of the given function `f`, which is usually an
+  # attribute set that expects its final, non-recursive representation as an
+  # argument:
+  #
+  #     f = self: { foo = "foo"; bar = "bar"; foobar = self.foo + self.bar; }
+  #
+  # Nix evaluates this recursion until all references to `self` have been
+  # resolved. At that point, the final result is returned and `f x = x` holds:
+  #
+  #     nix-repl> fix f
+  #     { bar = "bar"; foo = "foo"; foobar = "foobar"; }
+  #
+  # See https://en.wikipedia.org/wiki/Fixed-point_combinator for further
+  # details.
+  fix = f: let x = f x; in x;
+
+  # A variant of `fix` that records the original recursive attribute set in the
+  # result. This is useful in combination with the `extends` function to
+  # implement deep overriding. See pkgs/development/haskell-modules/default.nix
+  # for a concrete example.
+  fix' = f: let x = f x // { __unfix__ = f; }; in x;
+
+  # Modify the contents of an explicitly recursive attribute set in a way that
+  # honors `self`-references. This is accomplished with a function
+  #
+  #     g = self: super: { foo = super.foo + " + "; }
+  #
+  # that has access to the unmodified input (`super`) as well as the final
+  # non-recursive representation of the attribute set (`self`). `extends`
+  # differs from the native `//` operator insofar as that it's applied *before*
+  # references to `self` are resolved:
+  #
+  #     nix-repl> fix (extends g f)
+  #     { bar = "bar"; foo = "foo + "; foobar = "foo + bar"; }
+  #
+  # The name of the function is inspired by object-oriented inheritance, i.e.
+  # think of it as an infix operator `g extends f` that mimics the syntax from
+  # Java. It may seem counter-intuitive to have the "base class" as the second
+  # argument, but it's nice this way if several uses of `extends` are cascaded.
+  extends = f: rattrs: self: let super = rattrs self; in super // f self super;
+
+  # Create an overridable, recursive attribute set. For example:
+  #
+  #     nix-repl> obj = makeExtensible (self: { })
+  #
+  #     nix-repl> obj
+  #     { __unfix__ = «lambda»; extend = «lambda»; }
+  #
+  #     nix-repl> obj = obj.extend (self: super: { foo = "foo"; })
+  #
+  #     nix-repl> obj
+  #     { __unfix__ = «lambda»; extend = «lambda»; foo = "foo"; }
+  #
+  #     nix-repl> obj = obj.extend (self: super: { foo = super.foo + " + "; bar = "bar"; foobar = self.foo + self.bar; })
+  #
+  #     nix-repl> obj
+  #     { __unfix__ = «lambda»; bar = "bar"; extend = «lambda»; foo = "foo + "; foobar = "foo + bar"; }
+  makeExtensible = makeExtensibleWithCustomName "extend";
+
+  # Same as `makeExtensible` but the name of the extending attribute is
+  # customized.
+  makeExtensibleWithCustomName = extenderName: rattrs:
+    fix' rattrs // {
+      ${extenderName} = f: makeExtensibleWithCustomName extenderName (extends f rattrs);
+   };
+
  # Flip the order of the arguments of a binary function.
  flip = f: a: b: f b a;

-  # Apply function if argument is non-null
-  mapNullable = f: a: if isNull a then a else f a;
-
  # Pull in some builtins not included elsewhere.
  inherit (builtins)
-    pathExists readFile isBool
+    pathExists readFile isBool isFunction
    isInt add sub lessThan
    seq deepSeq genericClosure;

-  inherit (lib.strings) fileContents;
+  inherit (import ./strings.nix) fileContents;

  # Return the Nixpkgs version number.
  nixpkgsVersion =
@@ -71,52 +102,6 @@ rec {
  min = x: y: if x < y then x else y;
  max = x: y: if x > y then x else y;

-  /* Integer modulus
-
-     Example:
-       mod 11 10
-       => 1
-       mod 1 10
-       => 1
-  */
-  mod = base: int: base - (int * (builtins.div base int));
-
-  /* C-style comparisons
-
-     a < b,  compare a b => -1
-     a == b, compare a b => 0
-     a > b,  compare a b => 1
-  */
-  compare = a: b:
-    if a < b
-    then -1
-    else if a > b
-         then 1
-         else 0;
-
-  /* Split type into two subtypes by predicate `p`, take all elements
-     of the first subtype to be less than all the elements of the
-     second subtype, compare elements of a single subtype with `yes`
-     and `no` respectively.
-
-     Example:
-
-       let cmp = splitByAndCompare (hasPrefix "foo") compare compare; in
-
-       cmp "a" "z" => -1
-       cmp "fooa" "fooz" => -1
-
-       cmp "f" "a" => 1
-       cmp "fooa" "a" => -1
-       # while
-       compare "fooa" "a" => 1
-
-  */
-  splitByAndCompare = p: yes: no: a: b:
-    if p a
-    then if p b then yes a b else -1
-    else if p b then 1 else no a b;
-
  /* Reads a JSON file. */
  importJSON = path:
    builtins.fromJSON (builtins.readFile path);
@@ -135,29 +120,4 @@ rec {
  */
  warn = msg: builtins.trace "WARNING: ${msg}";
  info = msg: builtins.trace "INFO: ${msg}";
-
-  # | Add metadata about expected function arguments to a function.
-  # The metadata should match the format given by
-  # builtins.functionArgs, i.e. a set from expected argument to a bool
-  # representing whether that argument has a default or not.
-  # setFunctionArgs : (a → b) → Map String Bool → (a → b)
-  #
-  # This function is necessary because you can't dynamically create a
-  # function of the { a, b ? foo, ... }: format, but some facilities
-  # like callPackage expect to be able to query expected arguments.
-  setFunctionArgs = f: args:
-    { # TODO: Should we add call-time "type" checking like built in?
-      __functor = self: f;
-      __functionArgs = args;
-    };
-
-  # | Extract the expected function arguments from a function.
-  # This works both with nix-native { a, b ? foo, ... }: style
-  # functions and functions with args set with 'setFunctionArgs'. It
-  # has the same return type and semantics as builtins.functionArgs.
-  # setFunctionArgs : (a → b) → Map String Bool.
-  functionArgs = f: f.__functionArgs or (builtins.functionArgs f);
-
-  isFunction = f: builtins.isFunction f ||
-    (f ? __functor && isFunction (f.__functor f));
 }
--- a/lib/types.nix
+++ b/lib/types.nix
@@ -1,16 +1,15 @@
 # Definitions related to run-time type checking.  Used in particular
 # to type-check NixOS configurations.
-{ lib }:
-with lib.lists;
-with lib.attrsets;
-with lib.options;
-with lib.trivial;
-with lib.strings;
-let

-  inherit (lib.modules) mergeDefinitions filterOverrides;
-  outer_types =
+with import ./lists.nix;
+with import ./attrsets.nix;
+with import ./options.nix;
+with import ./trivial.nix;
+with import ./strings.nix;
+with {inherit (import ./modules.nix) mergeDefinitions filterOverrides; };
+
 rec {
+
  isType = type: x: (x._type or "") == type;

  setType = typeName: value: value // {
@@ -53,7 +52,7 @@ rec {
    { # Human-readable representation of the type, should be equivalent to
      # the type function name.
      name
-    , # Description of the type, defined recursively by embedding the wrapped type if any.
+    , # Description of the type, defined recursively by embedding the the wrapped type if any.
      description ? null
    , # Function applied to each definition that should return true if
      # its type-correct, false otherwise.
@@ -82,7 +81,7 @@ rec {
      #   name: name of the type
      #   type: type function.
      #   wrapped: the type wrapped in case of compound types.
-      #   payload: values of the type, two payloads of the same type must be
+      #   payload: values of the type, two payloads of the same type must be 
      #            combinable with the binOp binary operation.
      #   binOp: binary operation that merge two payloads of the same type.
      functor ? defaultFunctor name
@@ -93,9 +92,8 @@ rec {
    };


-  # When adding new types don't forget to document them in
-  # nixos/doc/manual/development/option-types.xml!
  types = rec {
+
    unspecified = mkOptionType {
      name = "unspecified";
    };
@@ -108,64 +106,11 @@ rec {
    };

    int = mkOptionType rec {
-        name = "int";
-        description = "signed integer";
-        check = isInt;
-        merge = mergeOneOption;
-      };
-
-    # Specialized subdomains of int
-    ints =
-      let
-        betweenDesc = lowest: highest:
-          "${toString lowest} and ${toString highest} (both inclusive)";
-        between = lowest: highest: assert lowest <= highest;
-          addCheck int (x: x >= lowest && x <= highest) // {
-            name = "intBetween";
-            description = "integer between ${betweenDesc lowest highest}";
-          };
-        ign = lowest: highest: name: docStart:
-          between lowest highest // {
-            inherit name;
-            description = docStart + "; between ${betweenDesc lowest highest}";
-          };
-        unsign = bit: range: ign 0 (range - 1)
-          "unsignedInt${toString bit}" "${toString bit} bit unsigned integer";
-        sign = bit: range: ign (0 - (range / 2)) (range / 2 - 1)
-          "signedInt${toString bit}" "${toString bit} bit signed integer";
-
-      in rec {
-        /* An int with a fixed range.
-        *
-        * Example:
-        *   (ints.between 0 100).check (-1)
-        *   => false
-        *   (ints.between 0 100).check (101)
-        *   => false
-        *   (ints.between 0 0).check 0
-        *   => true
-        */
-        inherit between;
-
-        unsigned = addCheck types.int (x: x >= 0) // {
-          name = "unsignedInt";
-          description = "unsigned integer, meaning >=0";
-        };
-        positive = addCheck types.int (x: x > 0) // {
-          name = "positiveInt";
-          description = "positive integer, meaning >0";
-        };
-        u8 = unsign 8 256;
-        u16 = unsign 16 65536;
-        # the biggest int a 64-bit Nix accepts is 2^63 - 1 (9223372036854775808), for a 32-bit Nix it is 2^31 - 1 (2147483647)
-        # the smallest int a 64-bit Nix accepts is -2^63 (-9223372036854775807), for a 32-bit Nix it is -2^31 (-2147483648)
-        # u32 = unsign 32 4294967296;
-        # u64 = unsign 64 18446744073709551616;
-
-        s8 = sign 8 256;
-        s16 = sign 16 65536;
-        # s32 = sign 32 4294967296;
-      };
+      name = "int";
+      description = "integer";
+      check = isInt;
+      merge = mergeOneOption;
+    };

    str = mkOptionType {
      name = "str";
@@ -174,13 +119,6 @@ rec {
      merge = mergeOneOption;
    };

-    strMatching = pattern: mkOptionType {
-      name = "strMatching ${escapeNixString pattern}";
-      description = "string matching the pattern ${pattern}";
-      check = x: str.check x && builtins.match pattern x != null;
-      inherit (str) merge;
-    };
-
    # Merge multiple definitions by concatenating them (with the given
    # separator between the values).
    separatedString = sep: mkOptionType rec {
@@ -232,16 +170,16 @@ rec {
    };

    # drop this in the future:
-    list = builtins.trace "`types.list` is deprecated; use `types.listOf` instead" types.listOf;
+    list = builtins.trace "`types.list' is deprecated; use `types.listOf' instead" types.listOf;

    listOf = elemType: mkOptionType rec {
      name = "listOf";
      description = "list of ${elemType.description}s";
      check = isList;
      merge = loc: defs:
-        map (x: x.value) (filter (x: x ? value) (concatLists (imap1 (n: def:
+        map (x: x.value) (filter (x: x ? value) (concatLists (imap (n: def:
          if isList def.value then
-            imap1 (m: def':
+            imap (m: def':
              (mergeDefinitions
                (loc ++ ["[definition ${toString n}-entry ${toString m}]"])
                elemType
@@ -249,17 +187,13 @@ rec {
              ).optionalValue
            ) def.value
          else
-            throw "The option value `${showOption loc}` in `${def.file}` is not a list.") defs)));
+            throw "The option value `${showOption loc}' in `${def.file}' is not a list.") defs)));
      getSubOptions = prefix: elemType.getSubOptions (prefix ++ ["*"]);
      getSubModules = elemType.getSubModules;
      substSubModules = m: listOf (elemType.substSubModules m);
      functor = (defaultFunctor name) // { wrapped = elemType; };
    };

-    nonEmptyListOf = elemType: 
-      let list = addCheck (types.listOf elemType) (l: l != []);
-      in list // { description = "non-empty " + list.description; };
-
    attrsOf = elemType: mkOptionType rec {
      name = "attrsOf";
      description = "attribute set of ${elemType.description}s";
@@ -284,7 +218,7 @@ rec {
          if isList def.value then
            { inherit (def) file;
              value = listToAttrs (
-                imap1 (elemIdx: elem:
+                imap (elemIdx: elem:
                  { name = elem.name or "unnamed-${toString defIdx}.${toString elemIdx}";
                    value = elem;
                  }) def.value);
@@ -297,14 +231,32 @@ rec {
        name = "loaOf";
        description = "list or attribute set of ${elemType.description}s";
        check = x: isList x || isAttrs x;
-        merge = loc: defs: attrOnly.merge loc (imap1 convertIfList defs);
+        merge = loc: defs: attrOnly.merge loc (imap convertIfList defs);
        getSubOptions = prefix: elemType.getSubOptions (prefix ++ ["<name?>"]);
        getSubModules = elemType.getSubModules;
        substSubModules = m: loaOf (elemType.substSubModules m);
        functor = (defaultFunctor name) // { wrapped = elemType; };
      };

-    # Value of given type but with no merging (i.e. `uniq list`s are not concatenated).
+    # List or element of ...
+    loeOf = elemType: mkOptionType rec {
+      name = "loeOf";
+      description = "element or list of ${elemType.description}s";
+      check = x: isList x || elemType.check x;
+      merge = loc: defs:
+        let
+          defs' = filterOverrides defs;
+          res = (head defs').value;
+        in
+        if isList res then concatLists (getValues defs')
+        else if lessThan 1 (length defs') then
+          throw "The option `${showOption loc}' is defined multiple times, in ${showFiles (getFiles defs)}."
+        else if !isString res then
+          throw "The option `${showOption loc}' does not have a string value, in ${showFiles (getFiles defs)}."
+        else res;
+      functor = (defaultFunctor name) // { wrapped = elemType; };
+    };
+
    uniq = elemType: mkOptionType rec {
      name = "uniq";
      inherit (elemType) description check;
@@ -315,7 +267,6 @@ rec {
      functor = (defaultFunctor name) // { wrapped = elemType; };
    };

-    # Null or value of ...
    nullOr = elemType: mkOptionType rec {
      name = "nullOr";
      description = "null or ${elemType.description}";
@@ -324,7 +275,7 @@ rec {
        let nrNulls = count (def: def.value == null) defs; in
        if nrNulls == length defs then null
        else if nrNulls != 0 then
-          throw "The option `${showOption loc}` is defined both null and not null, in ${showFiles (getFiles defs)}."
+          throw "The option `${showOption loc}' is defined both null and not null, in ${showFiles (getFiles defs)}."
        else elemType.merge loc defs;
      getSubOptions = elemType.getSubOptions;
      getSubModules = elemType.getSubModules;
@@ -332,11 +283,10 @@ rec {
      functor = (defaultFunctor name) // { wrapped = elemType; };
    };

-    # A submodule (like typed attribute set). See NixOS manual.
    submodule = opts:
      let
        opts' = toList opts;
-        inherit (lib.modules) evalModules;
+        inherit (import ./modules.nix) evalModules;
      in
      mkOptionType rec {
        name = "submodule";
@@ -352,17 +302,8 @@ rec {
          }).config;
        getSubOptions = prefix: (evalModules
          { modules = opts'; inherit prefix;
-            # This is a work-around due to the fact that some sub-modules,
-            # such as the one included in an attribute set, expects a "args"
-            # attribute to be given to the sub-module. As the option
-            # evaluation does not have any specific attribute name, we
-            # provide a default one for the documentation.
-            #
-            # This is mandatory as some option declaration might use the
-            # "name" attribute given as argument of the submodule and use it
-            # as the default of option declarations.
-            args.name = "&lt;name&gt;";
-          }).options;
+            # FIXME: hack to get shit to evaluate.
+            args = { name = ""; }; }).options;
        getSubModules = opts';
        substSubModules = m: submodule m;
        functor = (defaultFunctor name) // {
@@ -373,7 +314,6 @@ rec {
        };
      };

-    # A value from a set of allowed ones.
    enum = values:
      let
        show = v:
@@ -389,7 +329,6 @@ rec {
        functor = (defaultFunctor name) // { payload = values; binOp = a: b: unique (a ++ b); };
      };

-    # Either value of type `t1` or `t2`.
    either = t1: t2: mkOptionType rec {
      name = "either";
      description = "${t1.description} or ${t2.description}";
@@ -413,8 +352,6 @@ rec {
      functor = (defaultFunctor name) // { wrapped = [ t1 t2 ]; };
    };

-    # Either value of type `finalType` or `coercedType`, the latter is
-    # converted to `finalType` using `coerceFunc`.
    coercedTo = coercedType: coerceFunc: finalType:
      assert coercedType.getSubModules == null;
      mkOptionType rec {
@@ -449,6 +386,5 @@ rec {
    addCheck = elemType: check: elemType // { check = x: elemType.check x && check x; };

  };
-};

-in outer_types // outer_types.types
+}
--- a/lib/versions.nix
+++ b/lib/versions.nix
@@ -1,47 +0,0 @@
-/* Version string functions. */
-{ lib }:
-
-let
-
-  splitVersion = builtins.splitVersion or (lib.splitString ".");
-
-in
-
-rec {
-
-  /* Get the major version string from a string.
-
-    Example:
-      major "1.2.3"
-      => "1"
-  */
-  major = v: builtins.elemAt (splitVersion v) 0;
-
-  /* Get the minor version string from a string.
-
-    Example:
-      minor "1.2.3"
-      => "2"
-  */
-  minor = v: builtins.elemAt (splitVersion v) 1;
-
-  /* Get the patch version string from a string.
-
-    Example:
-      patch "1.2.3"
-      => "3"
-  */
-  patch = v: builtins.elemAt (splitVersion v) 2;
-
-  /* Get string of the first two parts (major and minor)
-     of a version string.
-
-     Example:
-       majorMinor "1.2.3"
-       => "1.2"
-  */
-  majorMinor = v:
-    builtins.concatStringsSep "."
-    (lib.take 2 (splitVersion v));
-
-}
--- a/maintainers/docker/.dockerignore
+++ b/maintainers/docker/.dockerignore
@@ -0,0 +1,14 @@
+*~
+,*
+.*.swp
+.*.swo
+result
+result-*
+/doc/NEWS.html
+/doc/NEWS.txt
+/doc/manual.html
+/doc/manual.pdf
+.version-suffix
+
+.DS_Store
+.git
--- a/maintainers/docker/Dockerfile
+++ b/maintainers/docker/Dockerfile
@@ -0,0 +1,12 @@
+FROM busybox
+
+RUN dir=`mktemp -d` && trap 'rm -rf "$dir"' EXIT && \
+    wget -O- https://nixos.org/releases/nix/nix-1.7/nix-1.7-x86_64-linux.tar.bz2  | bzcat | tar x -C $dir && \
+    mkdir -m 0755 /nix && USER=root sh $dir/*/install && \
+    echo ". /root/.nix-profile/etc/profile.d/nix.sh" >> /etc/profile
+
+ADD . /root/nix/nixpkgs
+ONBUILD ENV NIX_PATH nixpkgs=/root/nix/nixpkgs:nixos=/root/nix/nixpkgs/nixos
+ONBUILD ENV PATH /root/.nix-profile/bin:/root/.nix-profile/sbin:/bin:/sbin:/usr/bin:/usr/sbin
+ONBUILD ENV ENV /etc/profile
+ENV ENV /etc/profile
--- a/maintainers/maintainer-list.nix
+++ b/maintainers/maintainer-list.nix
--- a/Show More
+++ b/Show More
@@ -1 +1 @@
 .03
 .03