anchor.diff:        stopIfChanged = false;
         preStart =
           ''
  -        mkdir -p ${cfg.stateDir}/logs
  -        chmod 700 ${cfg.stateDir}
  -        chown -R ${cfg.user}:${cfg.group} ${cfg.stateDir}
  +        ${cfg.preStart}
           ${cfg.package}/bin/nginx -c ${configFile} -p ${cfg.stateDir} -t
           '';
         serviceConfig = {
  
positive.code: 
    configFile = pkgs.writeText "nginx.conf" ''
      user ${cfg.user} ${cfg.group};
      error_log stderr;
      daemon off;
  
      ${cfg.config}
  
negative.code:           Nginx package to use. This defaults to the stable version. Note
            that the nginx team recommends to use the mainline version which
            available in nixpkgs as <literal>nginxMainline</literal>.
          ";
        };
  
        logError = mkOption {
          default = "stderr";
          description = "
            Configures logging.
            The first parameter defines a file that will store the log. The
            special value stderr selects the standard error file. Logging to
            syslog can be configured by specifying the “syslog:” prefix.
            The second parameter determines the level of logging, and can be
            one of the following: debug, info, notice, warn, error, crit,
            alert, or emerg. Log levels above are listed in the order of
            increasing severity. Setting a certain log level will cause all
            messages of the specified and more severe log levels to be logged.
            If this parameter is omitted then error is used.
          ";
        };
  
        preStart =  mkOption {
          type = types.lines;
          default = ''
            test -d ${cfg.stateDir}/logs || mkdir -m 750 -p ${cfg.stateDir}/logs  
            test `stat -c %a ${cfg.stateDir}` = "750" || chmod 750 ${cfg.stateDir}
            test `stat -c %a ${cfg.stateDir}/logs` = "750" || chmod 750 ${cfg.stateDir}/logs
            chown -R ${cfg.user}:${cfg.group} ${cfg.stateDir}
          '';
          description = "
            Shell commands executed before the service's nginx is started.
          ";
        };
  
  