nixos-config/components/gui/xorg/xlock.nix

{ lib, pkgs, config, ... }:
with lib;
let

  name = "lock";

  # the lock program
  lockProgram = pkgs.writeShellScriptBin "${name}" ''
    ${pkgs.xlockmore}/bin/xlock -mode life1d -size 1
  '';

in
{
  config = mkIf config.components.gui.xorg.enable {
    environment.systemPackages = [
      lockProgram
      (pkgs.makeDesktopItem {
        name = "lock";
        desktopName = "lock";
        exec = "${lockProgram}/bin/lock";
        terminal = false;
      })
    ];
  };
}