public function integrate($integrations, ConfigurationInterface $config = null)
    {
        list($config, $container) = array($config ?: $this->config, static::$container);

        foreach ((array) $integrations as $item) {
            $integration = is_string($item) ? new $item : $item;

            $container = $integration->define($container, $config);
        }

        static::$container = $container;

        return $this;
    }