private function buildSystemCollections($locale, $userId)
    {
        $root = $this->getOrCreateRoot(SystemCollectionManagerInterface::COLLECTION_KEY, 'System', $locale, $userId);
        $collections = ['root' => $root->getId()];
        $collections = array_merge($collections, $this->iterateOverCollections($this->config, $userId, $root->getId()));

        $this->entityManager->flush();

        return $collections;
    }