diff --git a/core/lib/Drupal/Core/Cache/CacheFactory.php b/core/lib/Drupal/Core/Cache/CacheFactory.php
index 2697964..b756e91 100644
--- a/core/lib/Drupal/Core/Cache/CacheFactory.php
+++ b/core/lib/Drupal/Core/Cache/CacheFactory.php
@@ -14,7 +14,7 @@
 use Symfony\Component\DependencyInjection\ContainerAware;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 
-class CacheFactory extends ContainerAware {
+class CacheFactory extends ContainerAware implements CacheFactoryInterface {
 
   /**
    * The settings array.
diff --git a/core/lib/Drupal/Core/Cache/CacheFactoryInterface.php b/core/lib/Drupal/Core/Cache/CacheFactoryInterface.php
new file mode 100644
index 0000000..b25b273
--- /dev/null
+++ b/core/lib/Drupal/Core/Cache/CacheFactoryInterface.php
@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Cache\CacheFactoryInterface.
+ */
+
+namespace Drupal\Core\Cache;
+
+/**
+ * An interface defining cache factory classes.
+ */
+interface CacheFactoryInterface {
+
+  /**
+   * Gets a cache backend class for a given cache bin.
+   *
+   * @param string $bin
+   *   The cache bin for which a cache backend object should be returned.
+   *
+   * @return \Drupal\Core\Cache\CacheBackendInterface
+   *   The cache backend object associated with the specified bin.
+   */
+  public function get($bin);
+
+} 
diff --git a/core/lib/Drupal/Core/Cache/MemoryBackendFactory.php b/core/lib/Drupal/Core/Cache/MemoryBackendFactory.php
index 8e41224..c9e288d 100644
--- a/core/lib/Drupal/Core/Cache/MemoryBackendFactory.php
+++ b/core/lib/Drupal/Core/Cache/MemoryBackendFactory.php
@@ -7,16 +7,10 @@
 
 namespace Drupal\Core\Cache;
 
-class MemoryBackendFactory {
+class MemoryBackendFactory implements CacheFactoryInterface {
 
   /**
-   * Gets MemoryBackend for the specified cache bin.
-   *
-   * @param $bin
-   *   The cache bin for which the object is created.
-   *
-   * @return \Drupal\Core\Cache\MemoryBackend
-   *   The cache backend object for the specified cache bin.
+   * {@inheritdoc}
    */
   function get($bin) {
     return new MemoryBackend($bin);