{ lib, ... }:
{
  nixpkgs.overlays = [
    (
      final: prev:
      builtins.listToAttrs (
        map (pkg: {
          name = pkg;
          value =
            let
              argsPath = ./${pkg}/args.nix;
            in
            final.callPackage ./${pkg} (
              if (builtins.pathExists argsPath) then (import argsPath final) else { }
            );
        }) (builtins.attrNames (builtins.readDir ./.))
      )
    )
  ];

  imports = lib.pipe ./. [
    builtins.readDir
    (lib.filterAttrs (n: ty: ty == "directory" && builtins.pathExists ./${n}/nixos.nix))
    (lib.mapAttrsToList (n: _: ./${n}/nixos.nix))
  ];
}