https://nixos.org/guides/nix-pills/functions-and-imports.html
https://nixos.wiki/wiki/Overview_of_the_Nix_Language

{ pkgs, inputs, ... }: {
  imports = [
    inputs.hardware.nixosModules.common-cpu-intel
    ./hardware-configuration.nix

    ../common/global
    ../common/users/...

    # ../common/optional/...nix
  ];
  ...
}