$app->addGroup('/users', [
        // middleware1,
        // middleware2
    ], function ($app) {
        $app->get('/{name}', function ($request) {
            return \React\Http\Message\Response::plaintext(
                "Hello " . $request->getAttribute('name') . "!\n"
            );
        });
        $app->addGroup('/{name}/posts', [
            // middleware1,
            // middleware2
        ], function ($app) {
            $app->get('/{post}', function ($request) {
                return \React\Http\Message\Response::plaintext(
                    "Hello User {$request->getAttribute('name')} Posts " . $request->getAttribute('post') . "!\n"
                );
            });
        });
    });

    $app->addGroup('/posts', [
        // middleware1,
        // middleware2
    ], function ($app) {
        $app->get('/{post}', function ($request) {
            return \React\Http\Message\Response::plaintext(
                "Hello Posts " . $request->getAttribute('post') . "!\n"
            );
        });
    });