The dispatcher now constructs local bootstrap stages directly, so their target is represented entirely by localSystem. Remove the redundant crossSystem arguments and equality assertions from each local stage implementation.
Assisted-by: codex with gpt-5.6-sol-high
Allows having alternate hashed mirrors as fallbacks. Useful in case the
default hashed mirror is not accessible or doesn't have everything
needed.
Co-authored-by: Johan Herland <johan.herland@tweag.io>
Co-authored-by: Yuriy Taraday <yuriy.taraday@tweag.io>
Co-authored-by: Alexander Bantyev <balsoft@balsoft.ru>
This allows on-the-fly rewriting of URLs before they are passed from
fetchurl (or fetchurlBoot) to curl.
The intended use is to allow inserting company-internal mirrors, or
working around company firewalls and similar network restrictions,
without having to extensively patch across all of nixpkgs. Instead,
users can pass a function in their nixpkgs that performs the necessary
URL rewrites.
Co-authored-by: Alexander Bantyev <balsoft@balsoft.ru>
Copying instead of symlinking prevents leakage of the bootstrap FHS
into the 0->1 bootstrap stage. The symptom this addresses is libssh2
failing because it can't find libssl, since it is failing to use the
ld wrapper.
The status quo of `bash` not being interactive is frustrating for many users,
because trying to use it interactively is just messed up, and
`bashInteractive` is not intuitive and barely discoverable.
This was brought to my (and many others) attention by @stahnma in his
[talk at CfgMgmtCamp 2025](https://cfp.cfgmgmtcamp.org/ghent2025/talk/YUVUTN/),
where he highlighted this as one of the frustrations he ran into when
learning Nix.
Why this is fine:
- No reason for not making interactive the default was given in the original commit (6c6ff6f36f), but probably it was due to the increase in closure size
- The closure size only increases by 6.9MiB (19.5%) today, with the
added dependency on the store paths for readline and ncurses, which
are needed on systems in almost all cases anyways
- If somebody really needs to get a more minimal system, they can use
the newly-introduced `bashNonInteractive` instead now
- Though to apply it consistently, they'll need to do that in an
overlay like
```
final: prev: {
bash = self.bashNonInteractive;
}
```
Or alternatively using the `system.replaceDependencies.replacements`
NixOS option approach.
While there's also other such `*Interactive` packages that could use the
same treatment, `bash` is a great start.
This was already attempted before in
https://github.com/NixOS/nixpkgs/pull/151227, but was not continued for
unknown reason.
To avoid stdenv becoming bigger, all uses of bash in the (working)
stdenv's are changed to the explicitly non-interactive version here.
This commit will however still cause a mass rebuild for all packages (and reverse deps)
making use of the default bash.
After final improvements to the official formatter implementation,
this commit now performs the first treewide reformat of Nix files using it.
This is part of the implementation of RFC 166.
Only "inactive" files are reformatted, meaning only files that
aren't being touched by any PR with activity in the past 2 months.
This is to avoid conflicts for PRs that might soon be merged.
Later we can do a full treewide reformat to get the rest,
which should not cause as many conflicts.
A CI check has already been running for some time to ensure that new and
already-formatted files are formatted, so the files being reformatted here
should also stay formatted.
This commit was automatically created and can be verified using
nix-build a08b3a4d19.tar.gz \
--argstr baseRev b32a094368
result/bin/apply-formatting $NIXPKGS_PATH
The old stdenv didn't work, and was also impure. The new one works, and
is pure. Presently, the bootstrap tools are cross compiled into one small
nar and one large tar, which is then unpacked, patched, and split into
smaller derivations. Efforts were made to make the boot process as short
as possible - there are only two clangs built, and as many packages are
propagated between stages as possible while leaving the bootstrap tools
out of the final stdenv's closure.
Patch every `derivation` call in the bootsrap process to add it a
conditional `__contentAddressed` parameter.
That way, passing `contentAddressedByDefault` means that the entire
build closure of a system can be content addressed
crossOverlays only apply to the packages being built, not the build
packages. It is useful when you don’t care what is used to build your
packages, just what is being built. The idea relies heavily on the
cross compiling infrastructure. Using this implies that we need to
create a cross stdenv.
cc-wrapper may wrap a cc-compiler, but it doesn't need one to build
itself. (c.f. expand-response-params is a separate derivation.) This
helps avoid cycles on the cross stuff, in addition to removing a
useless dependency edge.
I could have been super careful with overrides in the stdenv to avoid
the mass rebuild, but I don't think it's worth it.
The long term goal is a big replace:
{ inherit system platform; } => buildPlatform
crossSystem => hostPlatform
stdenv.cross => targetPlatform
And additionally making sure each is defined even when not cross compiling.
This commit refactors the bootstrapping code along that vision, but leaves
the old identifiers with their null semantics in place so packages can be
modernized incrementally.
This patch add a new argument to Nixpkgs default expression named "overlays".
By default, the value of the argument is either taken from the environment variable `NIXPKGS_OVERLAYS`,
or from the directory `~/.nixpkgs/overlays/`. If the environment variable does not name a valid directory
then this mechanism would fallback on the home directory. If the home directory does not exists it will
fallback on an empty list of overlays.
The overlays directory should contain the list of extra Nixpkgs stages which would be used to extend the
content of Nixpkgs, with additional set of packages. The overlays, i-e directory, files, symbolic links
are used in alphabetical order.
The simplest overlay which extends Nixpkgs with nothing looks like:
```nix
self: super: {
}
```
More refined overlays can use `super` as the basis for building new packages, and `self` as a way to query
the final result of the fix-point.
An example of overlay which extends Nixpkgs with a small set of packages can be found at:
https://github.com/nbp/nixpkgs-mozilla/blob/nixpkgs-overlay/moz-overlay.nix
To use this file, checkout the repository and add a symbolic link to
the `moz-overlay.nix` file in `~/.nixpkgs/overlays` directory.
Introduce new abstraction, `stdenv/booter.nix` for composing bootstraping
stages, and use it everywhere for consistency. See that file for more doc.
Stdenvs besides Linux and Darwin are completely refactored to utilize this.
Those two, due to their size and complexity, are minimally edited for
easier reviewing.
No hashes should be changed.
- Non-cross stdenvs are honest and assert that `crossSystem` is null
- `crossSystem` is a mandatory argument to top-level/stage.nix, just like
`system` and `platform`
- Broken default arguments on stdenvs for testing are gone.
- All stdenvs (but little-used stdenvNix) take the same arguments for easy
testing.
