public function group($groupRoute, \Closure $callback)
    {
        // Track current base path
        $curBaseRoute = $this->routeBasePath;
        // Build new route base path string
        $this->routeBasePath .= $groupRoute;

        // Call the Closure callback
        call_user_func(function () use ($callback) {
            return $callback($this);
        });

        // Restore original route base path
        $this->routeBasePath = $curBaseRoute;
    }