Packaging/32bit Applications
Building software with 32bit gcc
Question: I'm invoking gcc with -m32 and it fails to find `gnu/stubs-32.h`
Answer (clever): you want to use pkgsi686Linux instead of pkgs, so things like pkgsi686Linux.stdenv.mkDerivation or pkgsi686Linux.callPackage then nix will give you 32bit everything[1]
Building multilib software
If a packages wants to compile both 32/64-bit executable, you need a compiler with multilib support.
In nixpkgs provides `multiStdenv.mkDerivation` that should be used instead `stdenv.mkDerivation`.
This is equivalent to using gcc-multilib in debian derivatives.