anchor.diff:  
         serviceConfig = {
           Type = "simple";
  -        ExecStart = "${opentabletdriver}/bin/otd-daemon -c ${opentabletdriver}/lib/OpenTabletDriver/Configurations";
  +        ExecStart = "${cfg.package}/bin/otd-daemon -c ${cfg.package}/lib/OpenTabletDriver/Configurations";
           Restart = "on-failure";
         };
       };
  
positive.code:   };
  
    config = mkIf cfg.enable {
      environment.systemPackages = with pkgs; [ opentabletdriver ];
  
      services.udev.packages = with pkgs; [ opentabletdriver ];
  
      boot.blacklistedKernelModules = cfg.blacklistedKernelModules;
  
  
negative.code:         '';
        };
  
        package = mkOption {
          type = types.package;
          default = pkgs.opentabletdriver;
          defaultText = "pkgs.opentabletdriver";
          description = ''
            OpenTabletDriver derivation to use.
          '';
        };
  
        daemon = {
          enable = mkOption {
            default = true;
  