anchor.diff:          };
   
           locker = mkOption {
  -          default = "xlock"; # default according to `man xautolock`
  -          example = "i3lock -i /path/to/img";
  -          type = types.string;
  +          default = "${pkgs.xlockmore}/bin/xlock"; # default according to `man xautolock`
  +          example = "${pkgs.i3lock}/bin/i3lock -i /path/to/img";
  +          type = types.str;
   
             description = ''
               The script to use when automatically locking the computer.
  
positive.code: 
          nowlocker = mkOption {
            default = null;
            example = "i3lock -i /path/to/img";
            type = types.nullOr types.string;
  
            description = ''
              The script to use when manually locking the computer with <command>xautolock -locknow</command>.
  
negative.code:           assertion = cfg.killer != null -> cfg.killtime >= 10;
            message = "killtime has to be at least 10 minutes according to `man xautolock`";
          }
        ] ++ (lib.flip map [ "locker" "notifier" "nowlocker" "killer" ]
          (option:
          {
            assertion = cfg."${option}" != null -> builtins.substring 0 1 cfg."${option}" == "/";
            message = "Please specify a canonical path for `services.xserver.xautolock.${option}`";
          })
        );
      };
    }
  