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