anchor.diff:        // then
         requestNavigator.getLogs(callsTo('registerDefaultHandler')).verify(happenedOnce);
       });
  -
  -    test('addNotFoundView with forgotten backslash - not matched route', () {
  +  });
  +
  +  group('(Backend real)', () {
  +    Backend backend;
  +    MockHttpServer server;
  +    RequestNavigator realRequestNavigator;
  +    Router realRouter;
  +    MockHMAC hmac;
  +    HttpBodyHandlerMock httpBodyHandler;
  +
  +    setUp(() {
  +      server = new MockHttpServer();
  +      hmac = new MockHMAC();
  +      httpBodyHandler = new HttpBodyHandlerMock();
  +
         //setUp real-like environment - so the backend made redirect callback will be called
  -      var realRouter = new Router("", {});
  -      var realRequestNavigator = new RequestNavigator(
  +      realRouter = new Router("", {});
  +      realRequestNavigator = new RequestNavigator(
             new StreamHttpRequestMock(), realRouter);
   
         backend = new Backend.config(server, realRouter, realRequestNavigator,
             hmac, httpBodyHandler.processRequest);
  -
  +    });
  +
  +    test('addNotFoundView handler called', () {
  +      // given
  +      HttpRequestMock request = new HttpRequestMock(Uri.parse('/whatever/'));
  +      HttpResponseMock response = request.response;
  +      backend.addNotFoundView(expectAsync1((_) {}, count : 1));
  +
  +      // when
  +      realRequestNavigator.processHttpRequest(request);
  +    });
  +
  +    test('addNotFoundView with forgotten backslash - not matched route', () {
         // given
         backend.addRoute('static', new Route('/static/'));
         backend.addView('static', (_) {});
  
positive.code: class StreamHttpRequestMock extends Mock implements Stream<HttpRequest> {}
  
  void main() {
    group('(Backend)', () {
      Backend backend;
      MockHttpServer server;
      MockRequestNavigator requestNavigator;
  
negative.code:     });
  
      test('addNotFoundView with forgotten backslash - matched route', () {
        // given
        backend.addRoute('directory', new Route('/static/*'));
        backend.addView('directory', expectAsync1((_) {}, count : 1));
        backend.addNotFoundView(expectAsync1((_) {}, count : 0));
  
        //incoming request
  