{ config, lib, pkgs, ... }: let cfg = config.hardware.brillo; in { options = { hardware.brillo = { enable = lib.mkEnableOption '' brillo in userspace. This will allow brightness control from users in the video group ''; }; }; config = lib.mkIf cfg.enable { services.udev.packages = [ pkgs.brillo ]; environment.systemPackages = [ pkgs.brillo ]; }; }