anchor.diff:  
   const int TIMEOUT_CALLBACK_SECONDS = 60;
   final String FAILED_URL = "http://www.dartdocs.org/failed/index.html";
  +final String COFNIG_FILE = "bin/config.json";
   
   class IsolateBuildIndex {
     Duration _timeout = const Duration(seconds: TIMEOUT_CALLBACK_SECONDS);
  
positive.code:       req.response.close();
      }
  
      HttpServer.bind(InternetAddress.LOOPBACK_IP_V4, 8887).then((server) {
        var router = new Router(server)
          // Associate callbacks with URLs.
          ..serve(buildIndexHtmlUrl, method: 'GET').listen(buildIndexHtml)
  
negative.code:   void _initServer() {
      final buildIndexHtmlUrl = new UrlPattern(r'/buildIndexHtml');
      final healthCheckUrl = new UrlPattern(r'/health');
      final SERVER_PORT = 8887;
  
      void buildIndexHtml(HttpRequest req) {
        _fetchAndBuild();
  