anchor.diff:               throw "invalid daemon type `${job.daemonType}'"
             )}
   
  +          ${optionalString (job.setuid != "") ''
  +            setuid ${job.setuid}
  +          ''}
  +
  +          ${optionalString (job.setgid != "") ''
  +            setuid ${job.setgid}
  +          ''}
  +
             ${job.extraConfig}
           '';
   
  
positive.code:     # do status queries.
      services.dbus.packages = [ upstart ];
  
    };
  
  }
  
negative.code: 
    upstart = pkgs.upstart;
  
    userExists = u:
      (u == "") || any (uu: uu.name == u) (attrValues config.users.extraUsers);
  
    groupExists = g:
      (g == "") || any (gg: gg.name == g) (attrValues config.users.extraGroups);
  
    # From a job description, generate an Upstart job file.
    makeJob = job:
  