{
  system ? builtins.currentSystem,
  sources ? import ./npins,
  nixpkgs ? sources.nixpkgs,
  darwin ? sources.darwin,
  pkgs ? import nixpkgs { 
    inherit system; 
    overlays = [ "${darwin}/overlay.nix" ];
  },
}:
pkgs.nix-darwin [
  ({ test, lib, pkgs, ... }: { environment.systemPackages = [ (lib.traceValFn (_: test) pkgs.fish) ]; })
  { _module.args.test = "hello"; }
  { system.stateVersion = 6; }
]