diff --git a/core/lib/Drupal/Core/Entity/EntityManager.php b/core/lib/Drupal/Core/Entity/EntityManager.php
index d21932f..6e16c64 100644
--- a/core/lib/Drupal/Core/Entity/EntityManager.php
+++ b/core/lib/Drupal/Core/Entity/EntityManager.php
@@ -92,6 +92,13 @@ class EntityManager extends PluginManagerBase implements EntityManagerInterface
   protected $fieldDefinitions;
 
   /**
+   * Static cache of storage field definitions per entity type.
+   *
+   * @var array
+   */
+  protected $storageFieldDefinitions;
+
+  /**
    * The root paths.
    *
    * @see self::__construct().
@@ -480,16 +487,18 @@ protected function buildBundleFieldDefinitions($entity_type_id, $bundle, array $
    */
   public function getStorageFieldDefinitions($entity_type_id) {
     if (!isset($this->storageFieldDefinitions[$entity_type_id])) {
+      $base_field_definitions = $this->getBaseFieldDefinitions($entity_type_id);
       // Not prepared, try to load from cache.
       $cid = 'entity_storage_field_definitions:' . $entity_type_id . ':' . $this->languageManager->getCurrentLanguage()->id;
       if ($cache = $this->cache->get($cid)) {
-        $this->storageFieldDefinitions[$entity_type_id] = $cache->data;
+        $storage_field_definitions = $cache->data;
       }
       else {
         // Rebuild the definitions and put it into the cache.
-        $this->storageFieldDefinitions[$entity_type_id] = $this->buildStorageFieldDefinitions($entity_type_id);
-        $this->cache->set($cid, $this->storageFieldDefinitions[$entity_type_id], Cache::PERMANENT, array('entity_types' => TRUE, 'entity_field_info' => TRUE));
+        $storage_field_definitions = $this->buildStorageFieldDefinitions($entity_type_id);
+        $this->cache->set($cid, $storage_field_definitions, Cache::PERMANENT, array('entity_types' => TRUE, 'entity_field_info' => TRUE));
       }
+      $this->storageFieldDefinitions[$entity_type_id] = $base_field_definitions + $storage_field_definitions;
     }
     return $this->storageFieldDefinitions[$entity_type_id];
   }
@@ -537,6 +546,7 @@ protected function buildStorageFieldDefinitions($entity_type_id) {
   public function clearCachedFieldDefinitions() {
     $this->baseFieldDefinitions = array();
     $this->fieldDefinitions = array();
+    $this->storageFieldDefinitions = array();
     Cache::deleteTags(array('entity_field_info' => TRUE));
   }
 
diff --git a/core/lib/Drupal/Core/Entity/EntityManagerInterface.php b/core/lib/Drupal/Core/Entity/EntityManagerInterface.php
index 424af7d..389c320 100644
--- a/core/lib/Drupal/Core/Entity/EntityManagerInterface.php
+++ b/core/lib/Drupal/Core/Entity/EntityManagerInterface.php
@@ -57,6 +57,28 @@ public function getBaseFieldDefinitions($entity_type_id);
   public function getFieldDefinitions($entity_type_id, $bundle);
 
   /**
+   * Gets the storage field definitions for a content entity type.
+   *
+   * This returns all storage field definitions for base fields and bundle
+   * fields of an entity type. Note that storage field definitions of a base
+   * fields equal the full base field definition (i.e. they implement
+   * \Drupal\Core\Field\FieldDefinitionInterface), while the storage fields for
+   * bundle fields may implement
+   * \Drupal\Core\Field\FieldStorageDefinitionInterface only.
+   *
+   * @param string $entity_type_id
+   *   The entity type ID. Only entity types that implement
+   *   \Drupal\Core\Entity\ContentEntityInterface are supported.
+   *
+   * @return \Drupal\Core\Field\FieldStorageDefinitionInterface[]
+   *   The array of storage field definitions for the entity type, keyed by
+   *   field name.
+   *
+   * @see \Drupal\Core\Field\FieldStorageDefinitionInterface
+   */
+  public function getStorageFieldDefinitions($entity_type_id);
+
+  /**
    * Creates a new access controller instance.
    *
    * @param string $entity_type
diff --git a/core/lib/Drupal/Core/Field/FieldStorageDefinitionInterface.php b/core/lib/Drupal/Core/Field/FieldStorageDefinitionInterface.php
index 506f272..645ef55 100644
--- a/core/lib/Drupal/Core/Field/FieldStorageDefinitionInterface.php
+++ b/core/lib/Drupal/Core/Field/FieldStorageDefinitionInterface.php
@@ -15,6 +15,8 @@
  * stored. While field definitions may differ by entity bundle, all of those
  * bundle fields have to share the same common field storage definition. Thus,
  * field storage definitions can be defined by entity type only.
+ *
+ * @see hook_entity_storage_field_info()
  */
 interface FieldStorageDefinitionInterface {
 
diff --git a/core/modules/field/field.module b/core/modules/field/field.module
index 52f3996..6970468 100644
--- a/core/modules/field/field.module
+++ b/core/modules/field/field.module
@@ -174,6 +174,15 @@ function field_system_info_alter(&$info, Extension $file, $type) {
 }
 
 /**
+ * Implements hook_entity_storage_field_info().
+ */
+function field_entity_storage_field_info(\Drupal\Core\Entity\EntityTypeInterface $entity_type) {
+  if ($entity_type->isFieldable()) {
+    return Field::fieldInfo()->getFields();
+  }
+}
+
+/**
  * Implements hook_entity_bundle_field_info().
  */
 function field_entity_bundle_field_info(EntityTypeInterface $entity_type, $bundle, array $base_field_definitions) {
diff --git a/core/modules/system/entity.api.php b/core/modules/system/entity.api.php
index c960371..f2b41c2 100644
--- a/core/modules/system/entity.api.php
+++ b/core/modules/system/entity.api.php
@@ -705,6 +705,9 @@ function hook_entity_base_field_info_alter(&$fields, \Drupal\Core\Entity\EntityT
 /**
  * Provides field definitions for a specific bundle within an entity type.
  *
+ * Bundles fields either have to override an existing base field, or need to
+ * provide a storage field via hook_entity_storage_field_info().
+ *
  * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
  *   The entity type definition.
  * @param string $bundle
@@ -717,6 +720,8 @@ function hook_entity_base_field_info_alter(&$fields, \Drupal\Core\Entity\EntityT
  *
  * @see hook_entity_base_field_info()
  * @see hook_entity_base_field_info_alter()
+ * @see hook_entity_storage_field_info()
+ * @see hook_entity_storage_field_info_alter()
  * @see hook_entity_bundle_field_info_alter()
  * @see \Drupal\Core\Field\FieldDefinitionInterface
  * @see \Drupal\Core\Entity\EntityManagerInterface::getFieldDefinitions()
@@ -755,6 +760,49 @@ function hook_entity_bundle_field_info_alter(&$fields, \Drupal\Core\Entity\Entit
 }
 
 /**
+ * Provides storage field definitions for a content entity type.
+ *
+ * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
+ *   The entity type definition.
+ *
+ * @return \Drupal\Core\Field\FieldStorageDefinitionInterface[]
+ *   An array of storage field definitions, keyed by field name.
+ *
+ * @see hook_entity_storage_field_info_alter()
+ * @see \Drupal\Core\Field\FieldStorageDefinitionInterface
+ * @see \Drupal\Core\Entity\EntityManagerInterface::getStorageFieldDefinitions()
+ */
+function hook_entity_storage_field_info(\Drupal\Core\Entity\EntityTypeInterface $entity_type) {
+  if ($entity_type->id() == 'node') {
+    $fields = array();
+    $fields['mymodule_text'] = FieldDefinition::create('string')
+      ->setLabel(t('The text'))
+      ->setDescription(t('A text property added by mymodule.'))
+      ->setComputed(TRUE)
+      ->setClass('\Drupal\mymodule\EntityComputedText');
+
+    return $fields;
+  }
+}
+
+/**
+ * Alters storage field definitions for a content entity type.
+ *
+ * @param \Drupal\Core\Field\FieldStorageDefinitionInterface[] $fields
+ *   The array of storage field definitions for the entity type.
+ * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
+ *   The entity type definition.
+ *
+ * @see hook_entity_storage_field_info()
+ */
+function hook_entity_storage_field_info_alter(&$fields, \Drupal\Core\Entity\EntityTypeInterface $entity_type) {
+  // Alter the max_length setting.
+  if ($entity_type->id() == 'node' && !empty($fields['mymodule_text'])) {
+    $fields['mymodule_text']->setSetting('max_length', 128);
+  }
+}
+
+/**
  * Alter entity operations.
  *
  * @param array $operations