nixos-config/modules/workspace/light.nix

{ config, pkgs, lib, ... }:
{
  programs.light.enable = config.deviceSpecific.isLaptop;
  services.actkbd = {
    enable = config.deviceSpecific.isLaptop;
    bindings = map (x:
    x // {
      events = ["key"];
      attributes = ["exec"];
    }) ([
      {
        keys = [225];
        command = "${pkgs.light}/bin/light -A 10";
      }
      {
        keys = [224];
        command = "${pkgs.light}/bin/light -U 10";
      }
      {
        keys = [431];
        command = (toString (pkgs.writeTextFile {
          name = "dark-script";
          text = ''
            if [[ `${pkgs.light}/bin/light` -eq 0 ]]
            then
              ${pkgs.light}/bin/light -I
            else
              ${pkgs.light}/bin/light -O
              ${pkgs.light}/bin/light -S 0
            fi'';
          executable = true;
        }));
      }
    ]);
  };
}