anchor.diff:            "${cfg.package}/bin/logstash agent " +
             "-w ${toString cfg.filterWorkers} " +
             ops havePluginPath "--pluginpath ${pluginPath} " +
  +          "${verbosityFlag} " +
             "--watchdog-timeout ${toString cfg.watchdogTimeout} " +
             "-f ${writeText "logstash.conf" ''
               input {
  
positive.code:   pluginPath = lib.concatStringsSep ":" cfg.plugins;
    havePluginPath = lib.length cfg.plugins > 0;
    ops = lib.optionalString;
  
  in
  
  
negative.code:         default = [ ];
          example = literalExample "[ pkgs.logstash-contrib ]";
          description = "The paths to find other logstash plugins in.";
        };
  
        logLevel = mkOption {
          type = types.enum [ "debug" "info" "warn" "error" "fatal" ];
          default = "warn";
          description = "Logging verbosity level.";
        };
  
        watchdogTimeout = mkOption {
  