- class \Drupal\Core\Cache\BackendChain implements \Drupal\Core\Cache\CacheTagsInvalidatorInterface, CacheBackendInterface
- class \Drupal\Core\Cache\ChainedFastBackend implements \Drupal\Core\Cache\CacheTagsInvalidatorInterface, CacheBackendInterface
- class \Drupal\Core\Cache\NullBackend implements CacheBackendInterface
- class \Drupal\Core\Update\UpdateBackend