anchor.diff:        serviceConfig.Restart = "always";
       };
     };
  +
   }
  
positive.code: { config, lib, pkgs, ... }:
  with lib;
  let
    cfg = config.services.redshift;
  
  in {
    options = {
      services.redshift.enable = mkOption {
        type = types.bool;
        default = false;
        example = true;
        description = "Enable Redshift to change your screen's colour temperature depending on the time of day";
      };
  
      services.redshift.latitude = mkOption {
        description = "Your current latitude";
        type = types.str;
      };
  
      services.redshift.longitude = mkOption {
        description = "Your current longitude";
        type = types.str;
      };
  
      services.redshift.temperature = {
        day = mkOption {
          description = "Colour temperature to use during day time";
          default = 5500;
          type = types.int;
        };
        night = mkOption {
          description = "Colour temperature to use during night time";
          default = 3700;
          type = types.int;
        };
      };
  
      services.redshift.brightness = {
        day = mkOption {
          description = "Screen brightness to apply during the day (between 0.1 and 1.0)";
          default = "1";
          type = types.str;
        };
        night = mkOption {
          description = "Screen brightness to apply during the night (between 0.1 and 1.0)";
          default = "1";
          type = types.str;
        };
      };
  
      services.redshift.extraOptions = mkOption {
        type = types.listOf types.str;
        default = [];
        example = [ "-v" "-m randr" ];
        description = "Additional command-line arguments to pass to the redshift(1) command";
      };
    };
  
  
negative.code:       after = [ "display-manager.service" ];
        wantedBy = [ "graphical.target" ];
        serviceConfig.ExecStart = ''
          ${cfg.package}/bin/redshift \
            -l ${cfg.latitude}:${cfg.longitude} \
            -t ${toString cfg.temperature.day}:${toString cfg.temperature.night} \
            -b ${toString cfg.brightness.day}:${toString cfg.brightness.night} \
  