diff --git a/pkgs/development/haskell-modules/generic-builder.nix b/pkgs/development/haskell-modules/generic-builder.nix
index bc43c39676c8..e637e446e649 100644
--- a/pkgs/development/haskell-modules/generic-builder.nix
+++ b/pkgs/development/haskell-modules/generic-builder.nix
@@ -338,9 +338,10 @@ stdenv.mkDerivation ({
     echo "Build with ${ghc}."
     ${optionalString (isLibrary && hyperlinkSource) "export PATH=${hscolour}/bin:$PATH"}
 
-    setupPackageConfDir="$TMPDIR/setup-package.conf.d"
+    builddir="$(mktemp -d)"
+    setupPackageConfDir="$builddir/setup-package.conf.d"
     mkdir -p $setupPackageConfDir
-    packageConfDir="$TMPDIR/package.conf.d"
+    packageConfDir="$builddir/package.conf.d"
     mkdir -p $packageConfDir
 
     setupCompileFlags="${concatStringsSep " " setupCompileFlags}"
@@ -418,7 +419,7 @@ stdenv.mkDerivation ({
     done
 
     echo setupCompileFlags: $setupCompileFlags
-    ${nativeGhcCommand} $setupCompileFlags --make -o Setup -odir $TMPDIR -hidir $TMPDIR $i
+    ${nativeGhcCommand} $setupCompileFlags --make -o Setup -odir $builddir -hidir $builddir $i
 
     runHook postCompileBuildDriver
   '';