protected function buildContainer()
    {
        // Get MicroCMS container builder
        $builder = new ContainerBuilder($this->getContainerBuilder());

        // Set file loader for config files
        $config_dirs = array($this->getSystemConfigDir(), $this->getConfigDir());
        $config_locator = new FileLocator($config_dirs);
        $builder->setConfigLocator($config_locator);

        // Finish container
        $container = $builder->prepareContainer();
        $container->set('kernel', $this);
        $container->set('kernel.config_locator', $config_locator);
        $container->compile();

        return($container);
    }