nixos/shells/crossShell.nix

{ crossSystem ? "aarch64-unknown-linux-musl" }:

let pkgs = import <nixpkgs> { crossSystem = { config = crossSystem; }; };
in pkgs.pkgsStatic.callPackage ({ mkShell, pkg-config, zlib, file }:
  mkShell {
    nativeBuildInputs = [ pkg-config file ];
    buildInputs = [ zlib ];
    env = { CROSS_COMPILE = crossSystem; };
  }) { }