anchor.diff:  
           preStart = ''
               mkdir -p ${cfg.dataDir}
  -            chown ${cfg.user} ${cfg.dataDir}
  +            chown ${user} ${cfg.dataDir}
           '';
   
           exec = ''
  -            ${pkgs.su}/bin/su -s ${pkgs.stdenv.shell} ${cfg.user} \
  +            ${pkgs.su}/bin/su -s ${pkgs.stdenv.shell} ${user} \
                   -c '${quassel}/bin/quasselcore --listen=${cfg.interface}\
                       --port=${toString cfg.portNumber} --configdir=${cfg.dataDir}'
           '';
  
positive.code:       };
  
        dataDir = mkOption {
          default = ''/home/${cfg.user}/.config/quassel-irc.org'';
          description = ''
            The directory holding configuration files, the SQlite database and the SSL Cert.
          '';
        };
  
        user = mkOption {
          default = "quassel";
          description = ''
            The user the Quassel daemon should run as.
          '';
        };
  
  
negative.code: 
    config = mkIf cfg.enable {
  
      users.extraUsers = mkIf (cfg.user == null) [
        { name = cfg.user;
          description = "Quassel IRC client daemon";
        }];
      
  
      jobs.quassel =
  