diff --git a/core/includes/menu.inc b/core/includes/menu.inc
index 08c7aff..caa757d 100644
--- a/core/includes/menu.inc
+++ b/core/includes/menu.inc
@@ -870,7 +870,7 @@ function menu_tail_load($arg, &$map, $index) {
  */
 function _menu_link_translate(&$item, $translate = FALSE) {
   if (!is_array($item['options'])) {
-    $item['options'] = unserialize($item['options']);
+    //$item['options'] = unserialize($item['options']);
   }
   if ($item['external']) {
     $item['access'] = 1;
@@ -1883,7 +1883,7 @@ function menu_navigation_links($menu_name, $level = 0) {
   foreach ($tree as $item) {
     if (!$item['link']['hidden']) {
       $class = '';
-      $l = $item['link']['localized_options'];
+      $l = $item['link']['localized_options']->getValue();
       $l['href'] = $item['link']['href'];
       $l['title'] = $item['link']['title'];
       if ($item['link']['in_active_trail']) {
@@ -2651,7 +2651,7 @@ function menu_get_active_breadcrumb() {
     }
 
     foreach ($active_trail as $parent) {
-      $breadcrumb[] = l($parent['title'], $parent['href'], $parent['localized_options']);
+      $breadcrumb[] = l($parent['title'], $parent['href'], is_array($parent['localized_options']) ? $parent['localized_options'] : $parent['localized_options']->getValue());
     }
   }
   return $breadcrumb;
@@ -2899,8 +2899,8 @@ function _menu_navigation_links_rebuild($menu) {
         $existing_item = NULL;
       }
 
-      if ($existing_item && $existing_item->customized) {
-        $parent_candidates[$existing_item->mlid] = $existing_item;
+      if ($existing_item && $existing_item->customized->value) {
+        $parent_candidates[$existing_item->id()] = $existing_item;
       }
       else {
         $menu_link = MenuLink::buildFromRouterItem($router_item);
@@ -2917,14 +2917,14 @@ function _menu_navigation_links_rebuild($menu) {
   // Updated and customized items whose router paths are gone need new ones.
   $menu_links = $menu_link_controller->loadUpdatedCustomized($paths);
   foreach ($menu_links as $menu_link) {
-    $router_path = _menu_find_router_path($menu_link->link_path);
-    if (!empty($router_path) && ($router_path != $menu_link->router_path || $menu_link->updated)) {
+    $router_path = _menu_find_router_path($menu_link->link_path->value);
+    if (!empty($router_path) && ($router_path != $menu_link->router_path->value || $menu_link->updated->value)) {
       // If the router path and the link path matches, it's surely a working
       // item, so we clear the updated flag.
-      $updated = $menu_link->updated && $router_path != $menu_link->link_path;
+      $updated = $menu_link->updated->value && $router_path != $menu_link->link_path->value;
 
-      $menu_link->router_path = $router_path;
-      $menu_link->updated = (int) $updated;
+      $menu_link->router_path->value = $router_path;
+      $menu_link->updated->value = (int) $updated;
       $menu_link_controller->save($menu_link);
     }
   }
diff --git a/core/includes/theme.inc b/core/includes/theme.inc
index 7bff76e..2e69daf 100644
--- a/core/includes/theme.inc
+++ b/core/includes/theme.inc
@@ -1762,9 +1762,9 @@ function theme_links($variables) {
       // Handle title-only text items.
       else {
         // Merge in default array properties into $link.
-        $link += array(
-          'html' => FALSE,
-        );
+        if (!isset($link['html'])) {
+          $link['html'] = FALSE;
+        }
         $item = ($link['html'] ? $link['title'] : check_plain($link['title']));
         if (isset($link['attributes'])) {
           $item = '<span' . new Attribute($link['attributes']) . '>' . $item . '</span>';
diff --git a/core/lib/Drupal/Core/Entity/Plugin/DataType/MapItem.php b/core/lib/Drupal/Core/Entity/Plugin/DataType/MapItem.php
new file mode 100644
index 0000000..073654b
--- /dev/null
+++ b/core/lib/Drupal/Core/Entity/Plugin/DataType/MapItem.php
@@ -0,0 +1,115 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Entity\Plugin\DataType\MapItem.
+ */
+
+namespace Drupal\Core\Entity\Plugin\DataType;
+
+use Drupal\Core\TypedData\Annotation\DataType;
+use Drupal\Core\Annotation\Translation;
+use Drupal\Core\Entity\Field\FieldItemBase;
+
+/**
+ * Defines the 'string_field' entity field item.
+ *
+ * @DataType(
+ *   id = "map_field",
+ *   label = @Translation("Map field item"),
+ *   description = @Translation("An entity field containing a map value."),
+ *   list_class = "\Drupal\Core\Entity\Field\Field"
+ * )
+ */
+class MapItem extends FieldItemBase implements \ArrayAccess {
+
+  /**
+   * Definitions of the contained properties.
+   *
+   * @see MapItem::getPropertyDefinitions()
+   *
+   * @var array
+   */
+  static $propertyDefinitions;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getPropertyDefinitions() {
+
+    if (!isset(static::$propertyDefinitions)) {
+      static::$propertyDefinitions['value'] = array(
+        'type' => 'map',
+        'label' => t('Array values'),
+      );
+    }
+    return static::$propertyDefinitions;
+  }
+
+  /**
+   * (PHP 5 &gt;= 5.0.0)<br/>
+   * Whether a offset exists
+   * @link http://php.net/manual/en/arrayaccess.offsetexists.php
+   * @param mixed $offset <p>
+   * An offset to check for.
+   * </p>
+   * @return boolean true on success or false on failure.
+   * </p>
+   * <p>
+   * The return value will be casted to boolean if non-boolean was returned.
+   */
+  public function offsetExists($offset) {
+    return !(isset($this->values[$offset]) && isset($this->properties[$offset]));
+  }
+
+  /**
+   * (PHP 5 &gt;= 5.0.0)<br/>
+   * Offset to retrieve
+   * @link http://php.net/manual/en/arrayaccess.offsetget.php
+   * @param mixed $offset <p>
+   * The offset to retrieve.
+   * </p>
+   * @return mixed Can return all value types.
+   */
+  public function offsetGet($offset) {
+    // There is either a property object or a plain value - possibly for a
+    // not-defined property. If we have a plain value, directly return it.
+    if (isset($this->values[$offset])) {
+      return $this->values[$offset];
+    }
+    elseif (isset($this->properties[$offset])) {
+      return $this->properties[$offset]->getValue();
+    }
+  }
+
+  /**
+   * (PHP 5 &gt;= 5.0.0)<br/>
+   * Offset to set
+   * @link http://php.net/manual/en/arrayaccess.offsetset.php
+   * @param mixed $offset <p>
+   * The offset to assign the value to.
+   * </p>
+   * @param mixed $value <p>
+   * The value to set.
+   * </p>
+   * @return void
+   */
+  public function offsetSet($offset, $value) {
+    $this->set($offset, $value);
+  }
+
+  /**
+   * (PHP 5 &gt;= 5.0.0)<br/>
+   * Offset to unset
+   * @link http://php.net/manual/en/arrayaccess.offsetunset.php
+   * @param mixed $offset <p>
+   * The offset to unset.
+   * </p>
+   * @return void
+   */
+  public function offsetUnset($offset) {
+    $this->set($offset, NULL);
+  }
+
+
+}
diff --git a/core/modules/menu/menu.module b/core/modules/menu/menu.module
index df5f602..c0df0f3 100644
--- a/core/modules/menu/menu.module
+++ b/core/modules/menu/menu.module
@@ -210,7 +210,7 @@ function menu_enable() {
   $system_link = reset($system_link);
 
   $base_link = entity_create('menu_link', array(
-    'menu_name' => $system_link->menu_name,
+    'menu_name' => $system_link->menu_name->value,
     'router_path' => 'admin/structure/menu/manage/%',
     'module' => 'menu',
   ));
@@ -223,8 +223,8 @@ function menu_enable() {
     $link->link_path = 'admin/structure/menu/manage/' . $menu->id();
 
     $query = Drupal::entityQuery('menu_link')
-      ->condition('link_path', $link->link_path)
-      ->condition('plid', $link->plid);
+      ->condition('link_path', $link->link_path->value)
+      ->condition('plid', $link->plid->value);
     $result = $query->execute();
 
     if (empty($result)) {
diff --git a/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkFormController.php b/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkFormController.php
index 8eb4458..a2118a3 100644
--- a/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkFormController.php
+++ b/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkFormController.php
@@ -8,7 +8,7 @@
 namespace Drupal\menu_link;
 
 use Drupal\Core\Entity\EntityControllerInterface;
-use Drupal\Core\Entity\EntityFormController;
+use Drupal\Core\Entity\EntityFormControllerNG;
 use Drupal\Core\Language\Language;
 use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\Core\Path\AliasManagerInterface;
@@ -19,7 +19,7 @@
 /**
  * Form controller for the node edit forms.
  */
-class MenuLinkFormController extends EntityFormController implements EntityControllerInterface {
+class MenuLinkFormController extends EntityFormControllerNG implements EntityControllerInterface {
 
   /**
    * The menu link storage controller.
@@ -81,37 +81,37 @@ public function form(array $form, array &$form_state) {
     if (!$menu_link->isNew()) {
       // Get the human-readable menu title from the given menu name.
       $titles = menu_get_menus();
-      $current_title = $titles[$menu_link->menu_name];
+      $current_title = $titles[$menu_link->menu_name->value];
 
       // Get the current breadcrumb and add a link to that menu's overview page.
       $breadcrumb = menu_get_active_breadcrumb();
-      $breadcrumb[] = l($current_title, 'admin/structure/menu/manage/' . $menu_link->menu_name);
+      $breadcrumb[] = l($current_title, 'admin/structure/menu/manage/' . $menu_link->menu_name->value);
       drupal_set_breadcrumb($breadcrumb);
     }
 
     $form['link_title'] = array(
       '#type' => 'textfield',
       '#title' => t('Menu link title'),
-      '#default_value' => $menu_link->link_title,
+      '#default_value' => $menu_link->link_title->value,
       '#description' => t('The text to be used for this link in the menu.'),
       '#required' => TRUE,
     );
     foreach (array('link_path', 'mlid', 'module', 'has_children', 'options') as $key) {
-      $form[$key] = array('#type' => 'value', '#value' => $menu_link->{$key});
+      $form[$key] = array('#type' => 'value', '#value' => $menu_link->{$key}->value);
     }
     // Any item created or edited via this interface is considered "customized".
     $form['customized'] = array('#type' => 'value', '#value' => 1);
 
     // We are not using url() when constructing this path because it would add
     // $base_path.
-    $path = $menu_link->link_path;
-    if (isset($menu_link->options['query'])) {
-      $path .= '?' . $this->urlGenerator->httpBuildQuery($menu_link->options['query']);
+    $path = $menu_link->link_path->value;
+    if (isset($menu_link->options->value['query'])) {
+      $path .= '?' . $this->urlGenerator->httpBuildQuery($menu_link->options->value['query']);
     }
-    if (isset($menu_link->options['fragment'])) {
-      $path .= '#' . $menu_link->options['fragment'];
+    if (isset($menu_link->options->value['fragment'])) {
+      $path .= '#' . $menu_link->options->value['fragment'];
     }
-    if ($menu_link->module == 'menu') {
+    if ($menu_link->module->value == 'menu') {
       $form['link_path'] = array(
         '#type' => 'textfield',
         '#title' => t('Path'),
@@ -125,33 +125,33 @@ public function form(array $form, array &$form_state) {
       $form['_path'] = array(
         '#type' => 'item',
         '#title' => t('Path'),
-        '#description' => l($menu_link->link_title, $menu_link->href, $menu_link->options),
+        '#description' => l($menu_link->link_title->value, $menu_link->href->value, $menu_link->options->value),
       );
     }
 
     $form['description'] = array(
       '#type' => 'textarea',
       '#title' => t('Description'),
-      '#default_value' => isset($menu_link->options['attributes']['title']) ? $menu_link->options['attributes']['title'] : '',
+      '#default_value' => isset($menu_link->options->value['attributes']['title']) ? $menu_link->options->value['attributes']['title'] : '',
       '#rows' => 1,
       '#description' => t('Shown when hovering over the menu link.'),
     );
     $form['enabled'] = array(
       '#type' => 'checkbox',
       '#title' => t('Enabled'),
-      '#default_value' => !$menu_link->hidden,
+      '#default_value' => !$menu_link->hidden->value,
       '#description' => t('Menu links that are not enabled will not be listed in any menu.'),
     );
     $form['expanded'] = array(
       '#type' => 'checkbox',
       '#title' => t('Show as expanded'),
-      '#default_value' => $menu_link->expanded,
+      '#default_value' => $menu_link->expanded->value,
       '#description' => t('If selected and this menu link has children, the menu will always appear expanded.'),
     );
 
     // Generate a list of possible parents (not including this link or descendants).
     $options = menu_parent_options(menu_get_menus(), $menu_link);
-    $default = $menu_link->menu_name . ':' . $menu_link->plid;
+    $default = $menu_link->menu_name->value . ':' . $menu_link->plid->target_id;
     if (!isset($options[$default])) {
       $default = 'tools:0';
     }
@@ -165,13 +165,13 @@ public function form(array $form, array &$form_state) {
     );
 
     // Get number of items in menu so the weight selector is sized appropriately.
-    $delta = $this->menuLinkStorageController->countMenuLinks($menu_link->menu_name);
+    $delta = $this->menuLinkStorageController->countMenuLinks($menu_link->menu_name->value);
     $form['weight'] = array(
       '#type' => 'weight',
       '#title' => t('Weight'),
       // Old hardcoded value.
       '#delta' => max($delta, 50),
-      '#default_value' => $menu_link->weight,
+      '#default_value' => $menu_link->weight->value,
       '#description' => t('Optional. In the menu, the heavier links will sink and the lighter links will be positioned nearer the top.'),
     );
 
@@ -181,13 +181,13 @@ public function form(array $form, array &$form_state) {
     // be configured individually.
     if ($this->moduleHandler->moduleExists('language')) {
       $language_configuration = language_get_default_configuration('menu_link', $menu_link->bundle());
-      $default_langcode = ($menu_link->isNew() ? $language_configuration['langcode'] : $menu_link->langcode);
+      $default_langcode = ($menu_link->isNew() ? $language_configuration['langcode'] : $menu_link->langcode->value);
       $language_show = $language_configuration['language_show'];
     }
     // Without Language module menu links inherit the menu language and no
     // language selector is shown.
     else {
-      $default_langcode = ($menu_link->isNew() ? entity_load('menu', $menu_link->menu_name)->langcode : $menu_link->langcode);
+      $default_langcode = ($menu_link->isNew() ? entity_load('menu', $menu_link->menu_name->value)->langcode : $menu_link->langcode->value);
       $language_show = FALSE;
     }
 
@@ -208,45 +208,45 @@ public function form(array $form, array &$form_state) {
   protected function actions(array $form, array &$form_state) {
     $element = parent::actions($form, $form_state);
     $element['submit']['#button_type'] = 'primary';
-    $element['delete']['#access'] = $this->entity->module == 'menu';
+    $element['delete']['#access'] = $this->entity->module->value == 'menu';
 
     return $element;
   }
 
   /**
-   * Overrides EntityFormController::validate().
+   * {@inheritdoc}
    */
   public function validate(array $form, array &$form_state) {
     $menu_link = $this->buildEntity($form, $form_state);
 
-    $normal_path = $this->pathAliasManager->getSystemPath($menu_link->link_path);
-    if ($menu_link->link_path != $normal_path) {
+    $normal_path = $this->pathAliasManager->getSystemPath($menu_link->link_path->value);
+    if ($menu_link->link_path->value != $normal_path) {
       drupal_set_message(t('The menu system stores system paths only, but will use the URL alias for display. %link_path has been stored as %normal_path', array('%link_path' => $menu_link->link_path, '%normal_path' => $normal_path)));
-      $menu_link->link_path = $normal_path;
+      $menu_link->link_path->value = $normal_path;
     }
-    if (!url_is_external($menu_link->link_path)) {
-      $parsed_link = parse_url($menu_link->link_path);
+    if (!url_is_external($menu_link->link_path->value)) {
+      $parsed_link = parse_url($menu_link->link_path->value);
       if (isset($parsed_link['query'])) {
-        $menu_link->options['query'] = array();
+        $menu_link->options->value['query'] = array();
         parse_str($parsed_link['query'], $menu_link->options['query']);
       }
       else {
         // Use unset() rather than setting to empty string
         // to avoid redundant serialized data being stored.
-        unset($menu_link->options['query']);
+        unset($menu_link->options->value['query']);
       }
       if (isset($parsed_link['fragment'])) {
-        $menu_link->options['fragment'] = $parsed_link['fragment'];
+        $menu_link->options->value['fragment'] = $parsed_link['fragment'];
       }
       else {
-        unset($menu_link->options['fragment']);
+        unset($menu_link->options->value['fragment']);
       }
-      if (isset($parsed_link['path']) && $menu_link->link_path != $parsed_link['path']) {
-        $menu_link->link_path = $parsed_link['path'];
+      if (isset($parsed_link['path']) && $menu_link->link_path->value != $parsed_link['path']) {
+        $menu_link->link_path->value = $parsed_link['path'];
       }
     }
-    if (!trim($menu_link->link_path) || !drupal_valid_path($menu_link->link_path, TRUE)) {
-      form_set_error('link_path', t("The path '@link_path' is either invalid or you do not have access to it.", array('@link_path' => $menu_link->link_path)));
+    if (!trim($menu_link->link_path->value) || !drupal_valid_path($menu_link->link_path->value, TRUE)) {
+      form_set_error('link_path', t("The path '@link_path' is either invalid or you do not have access to it.", array('@link_path' => $menu_link->link_path->value)));
     }
 
     parent::validate($form, $form_state);
@@ -261,11 +261,12 @@ public function submit(array $form, array &$form_state) {
 
     // The value of "hidden" is the opposite of the value supplied by the
     // "enabled" checkbox.
-    $menu_link->hidden = (int) !$menu_link->enabled;
-    unset($menu_link->enabled);
+    $menu_link->hidden->value = (int) !$menu_link->enabled->value;
+    // @todo Check out this 'enabled' stuff.
+//    unset($menu_link->enabled);
 
-    $menu_link->options['attributes']['title'] = $menu_link->description;
-    list($menu_link->menu_name, $menu_link->plid) = explode(':', $menu_link->parent);
+    $menu_link->options->value['attributes']['title'] = $menu_link->description->value;
+    list($menu_link->menu_name->value, $menu_link->plid->target_id) = explode(':', $menu_link->parent);
 
     return $menu_link;
   }
@@ -274,13 +275,9 @@ public function submit(array $form, array &$form_state) {
    * Overrides EntityFormController::save().
    */
   public function save(array $form, array &$form_state) {
-    $menu_link = $this->entity;
-
-    $saved = $menu_link->save();
-
-    if ($saved) {
+    if ($this->entity->save()) {
       drupal_set_message(t('The menu link has been saved.'));
-      $form_state['redirect'] = 'admin/structure/menu/manage/' . $menu_link->menu_name;
+      $form_state['redirect'] = 'admin/structure/menu/manage/' . $this->entity->menu_name->value;
     }
     else {
       drupal_set_message(t('There was an error saving the menu link.'), 'error');
@@ -292,7 +289,6 @@ public function save(array $form, array &$form_state) {
    * Overrides EntityFormController::delete().
    */
   public function delete(array $form, array &$form_state) {
-    $menu_link = $this->entity;
-    $form_state['redirect'] = 'admin/structure/menu/item/' . $menu_link->id() . '/delete';
+    $form_state['redirect'] = 'admin/structure/menu/item/' . $this->entity->id() . '/delete';
   }
 }
diff --git a/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkInterface.php b/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkInterface.php
index c185dc4..999385b 100644
--- a/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkInterface.php
+++ b/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkInterface.php
@@ -10,7 +10,6 @@
 use Symfony\Component\Routing\Route;
 use Drupal\Core\Entity\ContentEntityInterface;
 use Drupal\Core\Entity\EntityInterface;
-use Drupal\Core\Entity\EntityStorageControllerInterface;
 
 /**
  * Provides an interface defining a menu link entity.
@@ -85,7 +84,7 @@ public function setParents(EntityInterface $parent);
    *  - else, for system menu links (derived from hook_menu()), reparent
    *    based on the path hierarchy.
    *
-   * @param \Drupal\Core\Entity\EntityStorageControllerInterface $storage_controller
+   * @param \Drupal\menu_link\MenuLinkStorageControllerInterface $storage_controller
    *   Storage controller object.
    * @param array $parent_candidates
    *   An array of menu link entities keyed by mlid.
@@ -94,5 +93,5 @@ public function setParents(EntityInterface $parent);
    *   A menu link entity structure of the possible parent or FALSE if no valid
    *   parent has been found.
    */
-  public function findParent(EntityStorageControllerInterface $storage_controller, array $parent_candidates = array());
+  public function findParent(MenuLinkStorageControllerInterface $storage_controller, array $parent_candidates = array());
 }
diff --git a/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkStorageController.php b/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkStorageController.php
index 43d54ce..ebfd73a 100644
--- a/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkStorageController.php
+++ b/core/modules/menu_link/lib/Drupal/menu_link/MenuLinkStorageController.php
@@ -7,7 +7,7 @@
 
 namespace Drupal\menu_link;
 
-use Drupal\Core\Entity\DatabaseStorageController;
+use Drupal\Core\Entity\DatabaseStorageControllerNG;
 use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\EntityStorageException;
 use Drupal\Core\Database\Connection;
@@ -15,12 +15,9 @@
 use Symfony\Cmf\Component\Routing\RouteProviderInterface;
 
 /**
- * Controller class for menu links.
- *
- * This extends the Drupal\entity\DatabaseStorageController class, adding
- * required special handling for menu_link entities.
+ * Defines the storage controller class for menu links.
  */
-class MenuLinkStorageController extends DatabaseStorageController implements MenuLinkStorageControllerInterface {
+class MenuLinkStorageController extends DatabaseStorageControllerNG implements MenuLinkStorageControllerInterface {
 
   /**
    * Indicates whether the delete operation should re-parent children items.
@@ -44,16 +41,7 @@ class MenuLinkStorageController extends DatabaseStorageController implements Men
   protected $routeProvider;
 
   /**
-   * Overrides DatabaseStorageController::__construct().
-   *
-   * @param string $entity_type
-   *   The entity type for which the instance is created.
-   * @param array $entity_info
-   *   An array of entity info for the entity type.
-   * @param \Drupal\Core\Database\Connection $database
-   *   The database connection to be used.
-   * @param \Symfony\Cmf\Component\Routing\RouteProviderInterface $route_provider
-   *   The route provider service.
+   * {@inheritdoc}
    */
   public function __construct($entity_type, array $entity_info, Connection $database, RouteProviderInterface $route_provider) {
     parent::__construct($entity_type, $entity_info, $database);
@@ -90,7 +78,7 @@ public static function createInstance(ContainerInterface $container, $entity_typ
   }
 
   /**
-   * Overrides DatabaseStorageController::buildQuery().
+   * {@inheritdoc}
    */
   protected function buildQuery($ids, $revision_id = FALSE) {
     $query = parent::buildQuery($ids, $revision_id);
@@ -101,50 +89,60 @@ protected function buildQuery($ids, $revision_id = FALSE) {
   }
 
   /**
-   * Overrides DatabaseStorageController::attachLoad().
-   *
-   * @todo Don't call parent::attachLoad() at all because we want to be able to
-   * control the entity load hooks.
+   * {@inheritdoc}
    */
-  protected function attachLoad(&$menu_links, $load_revision = FALSE) {
+  protected function attachLoad(&$queried_entities, $load_revision = FALSE) {
     $routes = array();
 
-    foreach ($menu_links as &$menu_link) {
-      $menu_link->options = unserialize($menu_link->options);
+    foreach ($queried_entities as &$record) {
+      $record->options = unserialize($record->options);
 
       // Use the weight property from the menu link.
-      $menu_link->router_item['weight'] = $menu_link->weight;
+      $record->router_item['weight'] = $record->weight;
 
       // By default use the menu_name as type.
-      $menu_link->bundle = $menu_link->menu_name;
+      $record->bundle = $record->menu_name;
 
       // For all links that have an associated route, load the route object now
       // and save it on the object. That way we avoid a select N+1 problem later.
-      if ($menu_link->route_name) {
-        $routes[$menu_link->id()] = $menu_link->route_name;
+      if ($record->route_name) {
+        $routes[$record->{$this->idKey}] = $record->route_name;
       }
     }
 
+    parent::attachLoad($queried_entities, $load_revision);
+
     // Now mass-load any routes needed and associate them.
     if ($routes) {
       $route_objects = $this->routeProvider->getRoutesByNames($routes);
       foreach ($routes as $entity_id => $route) {
         // Not all stored routes will be valid on load.
         if (isset($route_objects[$route])) {
-          $menu_links[$entity_id]->setRouteObject($route_objects[$route]);
+          $queried_entities[$entity_id]->setRouteObject($route_objects[$route]);
         }
       }
     }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function mapFromStorageRecords(array $records, $load_revision = FALSE) {
+    $entities = parent::mapFromStorageRecords($records, $load_revision);
+
+    foreach ($entities as &$entity) {
+      foreach (static::$routerItemFields as $router_field) {
+        $entity->offsetSet($router_field, $records[$entity->id()]->{$router_field});
+      }
+    }
 
-    parent::attachLoad($menu_links, $load_revision);
+    return $entities;
   }
 
   /**
    * Overrides DatabaseStorageController::save().
    */
   public function save(EntityInterface $entity) {
-    $entity_class = $this->entityInfo['class'];
-
     // We return SAVED_UPDATED by default because the logic below might not
     // update the entity if its values haven't changed, so returning FALSE
     // would be confusing in that situation.
@@ -152,13 +150,19 @@ public function save(EntityInterface $entity) {
 
     $transaction = $this->database->startTransaction();
     try {
+      // Ensure we are dealing with the actual entity.
+      $entity = $entity->getNGEntity();
+
+      // Sync the changes made in the fields array to the internal values array.
+      $entity->updateOriginalValues();
+
       // Load the stored entity, if any.
       if (!$entity->isNew() && !isset($entity->original)) {
         $entity->original = entity_load_unchanged($this->entityType, $entity->id());
       }
 
       if ($entity->isNew()) {
-        $entity->mlid = $this->database->insert($this->entityInfo['base_table'])->fields(array('menu_name' => 'tools'))->execute();
+        $entity->mlid->value = $this->database->insert($this->entityInfo['base_table'])->fields(array('menu_name' => 'tools'))->execute();
         $entity->enforceIsNew();
       }
 
@@ -174,19 +178,45 @@ public function save(EntityInterface $entity) {
       // array_intersect_key() with the $entity as the first parameter because
       // $entity may have additional keys left over from building a router entry.
       // The intersect removes the extra keys, allowing a meaningful comparison.
-      if ($entity->isNew() || (array_intersect_key(get_object_vars($entity), get_object_vars($entity->original)) != get_object_vars($entity->original))) {
-        $return = drupal_write_record($this->entityInfo['base_table'], $entity, $this->idKey);
+      if ($entity->isNew() || (array_intersect_key($entity->getPropertyValues(), $entity->original->getPropertyValues()) != $entity->original->getPropertyValues())) {
+        // Create the storage record to be saved.
+        $record = $this->mapToStorageRecord($entity);
+        $return = drupal_write_record($this->entityInfo['base_table'], $record, $this->idKey);
 
         if ($return) {
           if (!$entity->isNew()) {
-            $this->resetCache(array($entity->{$this->idKey}));
+            // @todo, should a different value be returned when saving an entity
+            // with $isDefaultRevision = FALSE?
+            if (!$entity->isDefaultRevision()) {
+              $return = FALSE;
+            }
+
+            if ($this->revisionKey) {
+              $record->{$this->revisionKey} = $this->saveRevision($entity);
+            }
+            if ($this->dataTable) {
+              $this->savePropertyData($entity);
+            }
+            $this->resetCache(array($entity->id()));
             $entity->postSave($this, TRUE);
             $this->invokeFieldMethod('update', $entity);
             $this->invokeHook('update', $entity);
+            if ($this->dataTable) {
+              $this->invokeTranslationHooks($entity);
+            }
           }
           else {
             $return = SAVED_NEW;
-            $this->resetCache();
+            if ($this->revisionKey) {
+              $record->{$this->revisionKey} = $this->saveRevision($entity);
+            }
+            $entity->{$this->idKey}->value = $record->{$this->idKey};
+            if ($this->dataTable) {
+              $this->savePropertyData($entity);
+            }
+
+            // Reset general caches, but keep caches specific to certain entities.
+            $this->resetCache(array());
 
             $entity->enforceIsNew(FALSE);
             $entity->postSave($this, FALSE);
@@ -227,6 +257,10 @@ public function getPreventReparenting() {
    * {@inheritdoc}
    */
   public function loadUpdatedCustomized(array $router_paths) {
+    $menu_links = array();
+
+    // @todo This doesn't really make sense anymore with EntityNG.. and EFQ got
+    // OR condition support in the meantime, so convert this query.
     $query = parent::buildQuery(NULL);
     $query
       ->condition(db_or()
@@ -237,16 +271,12 @@ public function loadUpdatedCustomized(array $router_paths) {
         ->condition('customized', 1)
         )
       );
-    $query_result = $query->execute();
 
-    if (!empty($this->entityInfo['class'])) {
-      // We provide the necessary arguments for PDO to create objects of the
-      // specified entity class.
-      // @see Drupal\Core\Entity\EntityInterface::__construct()
-      $query_result->setFetchMode(\PDO::FETCH_CLASS, $this->entityInfo['class'], array(array(), $this->entityType));
+    if ($ids = $query->execute()->fetchCol(1)) {
+      $menu_links = $this->load($ids);
     }
 
-    return $query_result->fetchAllAssoc($this->idKey);
+    return $menu_links;
   }
 
   /**
@@ -270,13 +300,13 @@ public function loadModuleAdminTasks() {
    */
   public function updateParentalStatus(EntityInterface $entity, $exclude = FALSE) {
     // If plid == 0, there is nothing to update.
-    if ($entity->plid) {
+    if ($entity->plid->target_id) {
       // Check if at least one visible child exists in the table.
       $query = \Drupal::entityQuery($this->entityType);
       $query
-        ->condition('menu_name', $entity->menu_name)
+        ->condition('menu_name', $entity->menu_name->value)
         ->condition('hidden', 0)
-        ->condition('plid', $entity->plid)
+        ->condition('plid', $entity->plid->target_id)
         ->count();
 
       if ($exclude) {
@@ -286,7 +316,7 @@ public function updateParentalStatus(EntityInterface $entity, $exclude = FALSE)
       $parent_has_children = ((bool) $query->execute()) ? 1 : 0;
       $this->database->update('menu_links')
         ->fields(array('has_children' => $parent_has_children))
-        ->condition('mlid', $entity->plid)
+        ->condition('mlid', $entity->plid->target_id)
         ->execute();
     }
   }
@@ -299,20 +329,20 @@ public function findChildrenRelativeDepth(EntityInterface $entity) {
     // make sense to convert to EFQ?
     $query = $this->database->select('menu_links');
     $query->addField('menu_links', 'depth');
-    $query->condition('menu_name', $entity->menu_name);
+    $query->condition('menu_name', $entity->menu_name->value);
     $query->orderBy('depth', 'DESC');
     $query->range(0, 1);
 
     $i = 1;
     $p = 'p1';
-    while ($i <= MENU_MAX_DEPTH && $entity->{$p}) {
-      $query->condition($p, $entity->{$p});
+    while ($i <= MENU_MAX_DEPTH && $entity->{$p}->value) {
+      $query->condition($p, $entity->{$p}->value);
       $p = 'p' . ++$i;
     }
 
     $max_depth = $query->execute()->fetchField();
 
-    return ($max_depth > $entity->depth) ? $max_depth - $entity->depth : 0;
+    return ($max_depth > $entity->depth->value) ? $max_depth - $entity->depth->value : 0;
   }
 
   /**
@@ -321,14 +351,14 @@ public function findChildrenRelativeDepth(EntityInterface $entity) {
   public function moveChildren(EntityInterface $entity) {
     $query = $this->database->update($this->entityInfo['base_table']);
 
-    $query->fields(array('menu_name' => $entity->menu_name));
+    $query->fields(array('menu_name' => $entity->menu_name->value));
 
     $p = 'p1';
     $expressions = array();
-    for ($i = 1; $i <= $entity->depth; $p = 'p' . ++$i) {
-      $expressions[] = array($p, ":p_$i", array(":p_$i" => $entity->{$p}));
+    for ($i = 1; $i <= $entity->depth->value; $p = 'p' . ++$i) {
+      $expressions[] = array($p, ":p_$i", array(":p_$i" => $entity->{$p}->value));
     }
-    $j = $entity->original->depth + 1;
+    $j = $entity->original->depth->value + 1;
     while ($i <= MENU_MAX_DEPTH && $j <= MENU_MAX_DEPTH) {
       $expressions[] = array('p' . $i++, 'p' . $j++, array());
     }
@@ -336,7 +366,7 @@ public function moveChildren(EntityInterface $entity) {
       $expressions[] = array('p' . $i++, 0, array());
     }
 
-    $shift = $entity->depth - $entity->original->depth;
+    $shift = $entity->depth->value - $entity->original->depth->value;
     if ($shift > 0) {
       // The order of expressions must be reversed so the new values don't
       // overwrite the old ones before they can be used because "Single-table
@@ -349,10 +379,10 @@ public function moveChildren(EntityInterface $entity) {
     }
 
     $query->expression('depth', 'depth + :depth', array(':depth' => $shift));
-    $query->condition('menu_name', $entity->original->menu_name);
+    $query->condition('menu_name', $entity->original->menu_name->value);
     $p = 'p1';
-    for ($i = 1; $i <= MENU_MAX_DEPTH && $entity->original->{$p}; $p = 'p' . ++$i) {
-      $query->condition($p, $entity->original->{$p});
+    for ($i = 1; $i <= MENU_MAX_DEPTH && $entity->original->{$p}->value; $p = 'p' . ++$i) {
+      $query->condition($p, $entity->original->{$p}->value);
     }
 
     $query->execute();
@@ -376,7 +406,7 @@ public function countMenuLinks($menu_name) {
    * {@inheritdoc}
    */
   public function getParentFromHierarchy(EntityInterface $entity) {
-    $parent_path = $entity->link_path;
+    $parent_path = $entity->link_path->value;
     do {
       $parent = FALSE;
       $parent_path = substr($parent_path, 0, strrpos($parent_path, '/'));
@@ -387,7 +417,7 @@ public function getParentFromHierarchy(EntityInterface $entity) {
         ->condition('module', 'system')
         // We always respect the link's 'menu_name'; inheritance for router
         // items is ensured in _menu_router_build().
-        ->condition('menu_name', $entity->menu_name)
+        ->condition('menu_name', $entity->menu_name->value)
         ->condition('link_path', $parent_path);
 
       $result = $query->execute();
@@ -400,4 +430,176 @@ public function getParentFromHierarchy(EntityInterface $entity) {
     return $parent;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function baseFieldDefinitions() {
+    $properties['menu_name'] = array(
+      'label' => t('Menu name'),
+      'description' => t('The menu name. All links with the same menu name (such as "tools") are part of the same menu.'),
+      'type' => 'string_field',
+    );
+    $properties['mlid'] = array(
+      'label' => t('Menu link ID'),
+      'description' => t('The menu link ID.'),
+      'type' => 'integer_field',
+      'read-only' => TRUE,
+    );
+    $properties['uuid'] = array(
+      'label' => t('UUID'),
+      'description' => t('The menu link UUID.'),
+      'type' => 'uuid_field',
+      'read-only' => TRUE,
+    );
+    $properties['plid'] = array(
+      'label' => t('Parent ID'),
+      'description' => t('The parent menu link ID.'),
+      'type' => 'entity_reference_field',
+      'settings' => array('target_type' => 'menu_link'),
+    );
+    $properties['link_path'] = array(
+      'label' => t('Link path'),
+      'description' => t('The Drupal path or external path this link points to.'),
+      'type' => 'string_field',
+    );
+    $properties['router_path'] = array(
+      'label' => t('Router path'),
+      'description' => t('For links corresponding to a Drupal path (external = 0), this connects the link to a {menu_router}.path.'),
+      'type' => 'string_field',
+    );
+    $properties['langcode'] = array(
+      'label' => t('Language code'),
+      'description' => t('The menu link language code.'),
+      'type' => 'language_field',
+    );
+    $properties['link_title'] = array(
+      'label' => t('Title'),
+      'description' => t('The text displayed for the link, which may be modified by a title callback stored in {menu_router}.'),
+      'type' => 'string_field',
+    );
+    $properties['options'] = array(
+      'label' => t('Options'),
+      'description' => t('A serialized array of options to be passed to the url() or l() function, such as a query string or HTML attributes.'),
+      'type' => 'map_field',
+    );
+    $properties['module'] = array(
+      'label' => t('Module'),
+      'description' => t('The name of the module that generated this link.'),
+      'type' => 'string_field',
+    );
+    $properties['hidden'] = array(
+      'label' => t('Hidden'),
+      'description' => t('A flag for whether the link should be rendered in menus. (1 = a disabled menu item that may be shown on admin screens, -1 = a menu callback, 0 = a normal, visible link).'),
+      'type' => 'boolean_field',
+    );
+    $properties['external'] = array(
+      'label' => t('External'),
+      'description' => t('A flag to indicate if the link points to a full URL starting with a protocol, like http:// (1 = external, 0 = internal).'),
+      'type' => 'boolean_field',
+    );
+    $properties['has_children'] = array(
+      'label' => t('Has children'),
+      'description' => t('Flag indicating whether any links have this link as a parent (1 = children exist, 0 = no children).'),
+      'type' => 'boolean_field',
+    );
+    $properties['expanded'] = array(
+      'label' => t('Expanded'),
+      'description' => t('Flag for whether this link should be rendered as expanded in menus - expanded links always have their child links displayed, instead of only when the link is in the active trail (1 = expanded, 0 = not expanded).'),
+      'type' => 'boolean_field',
+    );
+    $properties['weight'] = array(
+      'label' => t('Weight'),
+      'description' => t('Link weight among links in the same menu at the same depth.'),
+      'type' => 'integer_field',
+    );
+    $properties['depth'] = array(
+      'label' => t('Depth'),
+      'description' => t('The depth relative to the top level. A link with plid == 0 will have depth == 1.'),
+      'type' => 'integer_field',
+    );
+    $properties['customized'] = array(
+      'label' => t('Customized'),
+      'description' => t('A flag to indicate that the user has manually created or edited the link (1 = customized, 0 = not customized).'),
+      'type' => 'boolean_field',
+    );
+    // @todo Declaring these pX properties as integer for the moment, we need to
+    // investigate if using 'entity_reference_field' cripples performance.
+    $properties['p1'] = array(
+      'label' => t('Parent 1'),
+      'description' => t('The first mlid in the materialized path.'),
+      'type' => 'integer_field',
+    );
+    $properties['p2'] = array(
+      'label' => t('Parent 2'),
+      'description' => t('The second mlid in the materialized path.'),
+      'type' => 'integer_field',
+    );
+    $properties['p3'] = array(
+      'label' => t('Parent 3'),
+      'description' => t('The third mlid in the materialized path.'),
+      'type' => 'integer_field',
+    );
+    $properties['p4'] = array(
+      'label' => t('Parent 4'),
+      'description' => t('The fourth mlid in the materialized path.'),
+      'type' => 'integer_field',
+    );
+    $properties['p5'] = array(
+      'label' => t('Parent 5'),
+      'description' => t('The fifth mlid in the materialized path.'),
+      'type' => 'integer_field',
+    );
+    $properties['p6'] = array(
+      'label' => t('Parent 6'),
+      'description' => t('The sixth mlid in the materialized path.'),
+      'type' => 'integer_field',
+    );
+    $properties['p7'] = array(
+      'label' => t('Parent 7'),
+      'description' => t('The seventh mlid in the materialized path.'),
+      'type' => 'integer_field',
+    );
+    $properties['p8'] = array(
+      'label' => t('Parent 8'),
+      'description' => t('The eighth mlid in the materialized path.'),
+      'type' => 'integer_field',
+    );
+    $properties['p9'] = array(
+      'label' => t('Parent 9'),
+      'description' => t('The ninth mlid in the materialized path.'),
+      'type' => 'integer_field',
+    );
+    $properties['updated'] = array(
+      'label' => t('Updated'),
+      'description' => t('Flag that indicates that this link was generated during the update from Drupal 5.'),
+      'type' => 'boolean_field',
+    );
+    $properties['route_name'] = array(
+      'label' => t('Route name'),
+      'description' => t('The machine name of a defined Symfony Route this menu item represents.'),
+      'type' => 'string_field',
+    );
+
+    // @todo Most of these should probably go away.
+    $properties['access'] = array(
+      'label' => t('(old router) Access'),
+      'description' => t(''),
+      'type' => 'boolean_field',
+      'computed' => TRUE,
+    );
+    $properties['in_active_trail'] = array(
+      'label' => t('In active trail'),
+      'description' => t(''),
+      'type' => 'boolean_field',
+      'computed' => TRUE,
+    );
+    $properties['localized_options'] = array(
+      'label' => t('Localized options'),
+      'description' => t(''),
+      'type' => 'map_field',
+      'computed' => TRUE,
+    );
+    return $properties;
+  }
+
 }
diff --git a/core/modules/menu_link/lib/Drupal/menu_link/Plugin/Core/Entity/MenuLink.php b/core/modules/menu_link/lib/Drupal/menu_link/Plugin/Core/Entity/MenuLink.php
index 7f227f8..245b9a4 100644
--- a/core/modules/menu_link/lib/Drupal/menu_link/Plugin/Core/Entity/MenuLink.php
+++ b/core/modules/menu_link/lib/Drupal/menu_link/Plugin/Core/Entity/MenuLink.php
@@ -7,17 +7,16 @@
 
 namespace Drupal\menu_link\Plugin\Core\Entity;
 
-use Drupal\menu_link\MenuLinkInterface;
-use Symfony\Component\Routing\Route;
-use Symfony\Component\HttpFoundation\Request;
-
-use Drupal\Core\Entity\Annotation\EntityType;
 use Drupal\Core\Annotation\Translation;
-use Drupal\Core\Entity\EntityStorageException;
+use Drupal\Core\Entity\Annotation\EntityType;
 use Drupal\Core\Entity\EntityInterface;
+use Drupal\Core\Entity\EntityNG;
 use Drupal\Core\Entity\EntityStorageControllerInterface;
-use Drupal\Core\Entity\ContentEntityInterface;
-use Drupal\Core\Entity\Entity;
+use Drupal\Core\Language\Language;
+use Drupal\menu_link\MenuLinkInterface;
+use Drupal\menu_link\MenuLinkStorageControllerInterface;
+use Symfony\Component\Routing\Route;
+use Symfony\Component\HttpFoundation\Request;
 
 /**
  * Defines the menu link entity class.
@@ -48,14 +47,14 @@
  *   }
  * )
  */
-class MenuLink extends Entity implements \ArrayAccess, MenuLinkInterface {
+class MenuLink extends EntityNG implements \ArrayAccess, MenuLinkInterface {
 
   /**
    * The link's menu name.
    *
-   * @var string
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
-  public $menu_name = 'tools';
+  public $menu_name;
 
   /**
    * The link's bundle.
@@ -67,21 +66,21 @@ class MenuLink extends Entity implements \ArrayAccess, MenuLinkInterface {
   /**
    * The menu link ID.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $mlid;
 
   /**
    * The menu link UUID.
    *
-   * @var string
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $uuid;
 
   /**
    * The parent link ID.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $plid;
 
@@ -96,89 +95,89 @@ class MenuLink extends Entity implements \ArrayAccess, MenuLinkInterface {
    * For links corresponding to a Drupal path (external = 0), this connects the
    * link to a {menu_router}.path for joins.
    *
-   * @var string
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $router_path;
 
   /**
    * The entity label.
    *
-   * @var string
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
-  public $link_title = '';
+  public $link_title;
 
   /**
    * A serialized array of options to be passed to the url() or l() function,
    * such as a query string or HTML attributes.
    *
-   * @var array
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
-  public $options = array();
+  public $options;
 
   /**
    * The name of the module that generated this link.
    *
-   * @var string
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
-  public $module = 'menu';
+  public $module;
 
   /**
    * A flag for whether the link should be rendered in menus.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
-  public $hidden = 0;
+  public $hidden;
 
   /**
    * A flag to indicate if the link points to a full URL starting with a
    * protocol, like http:// (1 = external, 0 = internal).
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $external;
 
   /**
    * Flag indicating whether any links have this link as a parent.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
-  public $has_children = 0;
+  public $has_children;
 
   /**
    * Flag for whether this link should be rendered as expanded in menus.
    * Expanded links always have their child links displayed, instead of only
    * when the link is in the active trail.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
-  public $expanded = 0;
+  public $expanded;
 
   /**
    * Link weight among links in the same menu at the same depth.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
-  public $weight = 0;
+  public $weight;
 
   /**
    * The depth relative to the top level. A link with plid == 0 will have
    * depth == 1.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $depth;
 
   /**
    * A flag to indicate that the user has manually created or edited the link.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
-  public $customized = 0;
+  public $customized;
 
   /**
    * The first entity ID in the materialized path.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    *
    * @todo Investigate whether the p1, p2, .. pX properties can be moved to a
    * single array property.
@@ -188,74 +187,93 @@ class MenuLink extends Entity implements \ArrayAccess, MenuLinkInterface {
   /**
    * The second entity ID in the materialized path.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $p2;
 
   /**
    * The third entity ID in the materialized path.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $p3;
 
   /**
    * The fourth entity ID in the materialized path.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $p4;
 
   /**
    * The fifth entity ID in the materialized path.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $p5;
 
   /**
    * The sixth entity ID in the materialized path.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $p6;
 
   /**
    * The seventh entity ID in the materialized path.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $p7;
 
   /**
    * The eighth entity ID in the materialized path.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $p8;
 
   /**
    * The ninth entity ID in the materialized path.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $p9;
 
   /**
    * The menu link modification timestamp.
    *
-   * @var int
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
-  public $updated = 0;
+  public $updated;
 
   /**
    * The name of the route associated with this menu link, if any.
    *
-   * @var string
+   * @var \Drupal\Core\Entity\Field\FieldInterface
    */
   public $route_name;
 
   /**
+   * Default values for the menu link.
+   *
+   * @var array
+   */
+  protected $values = array(
+    'langcode' => array(Language::LANGCODE_DEFAULT => array(0 => array('value' => Language::LANGCODE_NOT_SPECIFIED))),
+    'menu_name' => array(Language::LANGCODE_DEFAULT => array(0 => array('value' => 'tools'))),
+    'link_title' => array(Language::LANGCODE_DEFAULT => array(0 => array('value' => ''))),
+    'options' => array(Language::LANGCODE_DEFAULT => array(0 => array('value' => array()))),
+    'module' => array(Language::LANGCODE_DEFAULT => array(0 => array('value' => 'menu'))),
+    'hidden' => array(Language::LANGCODE_DEFAULT => array(0 => array('value' => 0))),
+    'has_children' => array(Language::LANGCODE_DEFAULT => array(0 => array('value' => 0))),
+    'expanded' => array(Language::LANGCODE_DEFAULT => array(0 => array('value' => 0))),
+    'weight' => array(Language::LANGCODE_DEFAULT => array(0 => array('value' => 0))),
+    'customized' => array(Language::LANGCODE_DEFAULT => array(0 => array('value' => 0))),
+    'updated' => array(Language::LANGCODE_DEFAULT => array(0 => array('value' => 0))),
+  );
+
+  /**
    * The route object associated with this menu link, if any.
    *
    * @var \Symfony\Component\Routing\Route
@@ -263,10 +281,35 @@ class MenuLink extends Entity implements \ArrayAccess, MenuLinkInterface {
   protected $routeObject;
 
   /**
-   * Overrides Entity::id().
+   * Crap coming from the old routing system.
+   *
+   * @todo Remove when we rip out the old routing system.
+   *
+   * @var array
+   */
+  protected $oldRouterItem = array();
+
+  /**
+   * Properties of the old routing system.
+   *
+   * @todo Remove when we rip out the old routing system.
+   *
+   * @var array
+   */
+  protected $oldRoutingProperties = array(
+    'path', 'load_functions', 'to_arg_functions', 'access_callback',
+    'access_arguments', 'page_callback', 'page_arguments', 'fit',
+    'number_parts', 'context', 'tab_parent', 'tab_root', 'title',
+    'title_callback', 'title_arguments', 'theme_callback', 'theme_arguments',
+    'type', 'description', 'description_callback', 'description_arguments',
+    'position', 'include_file', 'route_name',
+  );
+
+  /**
+   * {@inheritdoc}
    */
   public function id() {
-    return $this->mlid;
+    return $this->get('mlid')->value;
   }
 
   /**
@@ -277,11 +320,46 @@ public function bundle() {
   }
 
   /**
+   * {@inheritdoc}
+   */
+  protected function init() {
+    parent::init();
+    // We unset all defined properties, so magic getters apply.
+    unset($this->menu_name);
+    unset($this->mlid);
+    unset($this->uuid);
+    unset($this->plid);
+    unset($this->link_path);
+    unset($this->router_path);
+    unset($this->link_title);
+    unset($this->options);
+    unset($this->module);
+    unset($this->hidden);
+    unset($this->external);
+    unset($this->has_children);
+    unset($this->expanded);
+    unset($this->weight);
+    unset($this->depth);
+    unset($this->customized);
+    unset($this->p1);
+    unset($this->p2);
+    unset($this->p3);
+    unset($this->p4);
+    unset($this->p5);
+    unset($this->p6);
+    unset($this->p7);
+    unset($this->p8);
+    unset($this->p9);
+    unset($this->updated);
+    unset($this->route_name);
+  }
+
+  /**
    * Overrides Entity::createDuplicate().
    */
   public function createDuplicate() {
     $duplicate = parent::createDuplicate();
-    $duplicate->plid = NULL;
+    $duplicate->get('plid')->offsetGet(0)->set('value', NULL);
     return $duplicate;
   }
 
@@ -289,12 +367,12 @@ public function createDuplicate() {
    * {@inheritdoc}
    */
   public function getRoute() {
-    if (!$this->route_name) {
+    if (!$this->route_name->value) {
       return NULL;
     }
     if (!($this->routeObject instanceof Route)) {
       $route_provider = \Drupal::service('router.route_provider');
-      $this->routeObject = $route_provider->getRouteByName($this->route_name);
+      $this->routeObject = $route_provider->getRouteByName($this->route_name->value);
     }
     return $this->routeObject;
   }
@@ -316,11 +394,11 @@ public function reset() {
     // not stored anywhere else. Since resetting a link happens rarely and this
     // is a one-time operation, retrieving the full menu router does no harm.
     $menu = menu_get_router();
-    $router_item = $menu[$this->router_path];
+    $router_item = $menu[$this->router_path->value];
     $new_link = self::buildFromRouterItem($router_item);
     // Merge existing menu link's ID and 'has_children' property.
     foreach (array('mlid', 'has_children') as $key) {
-      $new_link->{$key} = $this->{$key};
+      $new_link->{$key}->value = $this->{$key}->value;
     }
     $new_link->save();
     return $new_link;
@@ -351,31 +429,70 @@ public static function buildFromRouterItem(array $item) {
   }
 
   /**
-   * Implements ArrayAccess::offsetExists().
+   * {@inheritdoc}
    */
   public function offsetExists($offset) {
-    return isset($this->{$offset});
+    if (in_array($offset, $this->oldRoutingProperties)) {
+      return isset($this->oldRouterItem[$offset]);
+    }
+
+    return isset($this->{$offset}->value);
+//    return isset($this->{$offset});
   }
 
   /**
-   * Implements ArrayAccess::offsetGet().
+   * {@inheritdoc}
    */
-  public function &offsetGet($offset) {
-    return $this->{$offset};
+  public function offsetGet($offset) {
+    if (in_array($offset, $this->oldRoutingProperties)) {
+      return $this->oldRouterItem[$offset];
+    }
+    elseif ($offset == 'localized_options' || $offset == 'options') {
+      return $this->{$offset}[0];
+    }
+    elseif ($this->getPropertyDefinition($offset)) {
+      return $this->{$offset}->value;
+    }
+    else {
+      return $this->{$offset};
+    }
   }
 
   /**
-   * Implements ArrayAccess::offsetSet().
+   * {@inheritdoc}
    */
   public function offsetSet($offset, $value) {
-    $this->{$offset} = $value;
+    if (in_array($offset, $this->oldRoutingProperties)) {
+      $this->oldRouterItem[$offset] = $value;
+    }
+    elseif ($this->getPropertyDefinition($offset)) {
+      $this->{$offset}->value = $value;
+    }
+    else {
+      $this->{$offset} = $value;
+    }
   }
 
   /**
-   * Implements ArrayAccess::offsetUnset().
+   * {@inheritdoc}
    */
   public function offsetUnset($offset) {
-    unset($this->{$offset});
+    if (in_array($offset, $this->oldRoutingProperties)) {
+      unset($this->oldRouterItem[$offset]);
+    }
+    else {
+      $this->{$offset}->value = NULL;
+    }
+//    unset($this->{$offset});
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function preCreate(EntityStorageControllerInterface $storage_controller, array &$values) {
+    if (empty($values['menu_name'])) {
+      $values['menu_name'] = $values['bundle'] = 'tools';
+    }
   }
 
   /**
@@ -389,10 +506,10 @@ public static function preDelete(EntityStorageControllerInterface $storage_contr
 
     foreach ($entities as $entity) {
       // Children get re-attached to the item's parent.
-      if ($entity->has_children) {
-        $children = $storage_controller->loadByProperties(array('plid' => $entity->plid));
+      if ($entity->has_children->value) {
+        $children = $storage_controller->loadByProperties(array('plid' => $entity->plid->target_id));
         foreach ($children as $child) {
-          $child->plid = $entity->plid;
+          $child->plid->target_id = $entity->plid->target_id;
           $storage_controller->save($child);
         }
       }
@@ -411,8 +528,8 @@ public static function postDelete(EntityStorageControllerInterface $storage_cont
       }
 
       // Store all menu names for which we need to clear the cache.
-      if (!isset($affected_menus[$entity->menu_name])) {
-        $affected_menus[$entity->menu_name] = $entity->menu_name;
+      if (!isset($affected_menus[$entity->menu_name->value])) {
+        $affected_menus[$entity->menu_name->value] = $entity->menu_name->value;
       }
     }
 
@@ -428,63 +545,64 @@ public static function postDelete(EntityStorageControllerInterface $storage_cont
   public function preSave(EntityStorageControllerInterface $storage_controller) {
     // This is the easiest way to handle the unique internal path '<front>',
     // since a path marked as external does not need to match a router path.
-    $this->external = (url_is_external($this->link_path) || $this->link_path == '<front>') ? 1 : 0;
+    $this->external->value = (url_is_external($this->link_path->value) || $this->link_path->value == '<front>') ? 1 : 0;
 
     // Try to find a parent link. If found, assign it and derive its menu.
     $parent_candidates = !empty($this->parentCandidates) ? $this->parentCandidates : array();
     $parent = $this->findParent($storage_controller, $parent_candidates);
     if ($parent) {
-      $this->plid = $parent->id();
-      $this->menu_name = $parent->menu_name;
+      $this->plid->target_id = $parent->id();
+      $this->menu_name->value = $parent->menu_name->value;
     }
     // If no corresponding parent link was found, move the link to the top-level.
     else {
-      $this->plid = 0;
+      $this->plid->target_id = 0;
     }
 
     // Directly fill parents for top-level links.
-    if ($this->plid == 0) {
-      $this->p1 = $this->id();
+    if ($this->plid->target_id == 0) {
+      $this->p1->value = $this->id();
       for ($i = 2; $i <= MENU_MAX_DEPTH; $i++) {
         $parent_property = "p$i";
-        $this->{$parent_property} = 0;
+        $this->{$parent_property}->value = 0;
       }
-      $this->depth = 1;
+      $this->depth->value = 1;
     }
     // Otherwise, ensure that this link's depth is not beyond the maximum depth
     // and fill parents based on the parent link.
     else {
-      if ($this->has_children && $this->original) {
+      if ($this->has_children->value && $this->original) {
         $limit = MENU_MAX_DEPTH - $storage_controller->findChildrenRelativeDepth($this->original) - 1;
       }
       else {
         $limit = MENU_MAX_DEPTH - 1;
       }
-      if ($parent->depth > $limit) {
+      if ($parent->depth->value > $limit) {
         return FALSE;
       }
-      $this->depth = $parent->depth + 1;
+      $this->depth->value = $parent->depth->value + 1;
       $this->setParents($parent);
     }
 
     // Need to check both plid and menu_name, since plid can be 0 in any menu.
-    if (isset($this->original) && ($this->plid != $this->original->plid || $this->menu_name != $this->original->menu_name)) {
+    if (isset($this->original) && ($this->plid->target_id != $this->original->plid->target_id || $this->menu_name->value != $this->original->menu_name->value)) {
       $storage_controller->moveChildren($this, $this->original);
     }
     // Find the router_path.
-    if (empty($this->router_path) || empty($this->original) || (isset($this->original) && $this->original->link_path != $this->link_path)) {
-      if ($this->external) {
-        $this->router_path = '';
+    if (empty($this->router_path->value) || empty($this->original) || (isset($this->original) && $this->original->link_path->value != $this->link_path->value)) {
+      if ($this->external->value) {
+        $this->router_path->value = '';
       }
       else {
         // Find the router path which will serve this path.
-        $this->parts = explode('/', $this->link_path, MENU_MAX_PARTS);
-        $this->router_path = _menu_find_router_path($this->link_path);
+        // @todo Where do we need 'parts'?
+        $this->parts = explode('/', $this->link_path->value, MENU_MAX_PARTS);
+        $this->router_path->value = _menu_find_router_path($this->link_path->value);
       }
     }
     // Find the route_name.
-    if (!isset($this->route_name)) {
-      $this->route_name = $this::findRouteName($this->link_path);
+    if (!isset($this->route_name->value)) {
+      $this->route_name->value = $this::findRouteName($this->link_path->value);
     }
   }
 
@@ -495,9 +613,9 @@ public function postSave(EntityStorageControllerInterface $storage_controller, $
     // Check the has_children status of the parent.
     $storage_controller->updateParentalStatus($this);
 
-    menu_cache_clear($this->menu_name);
-    if (isset($this->original) && $this->menu_name != $this->original->menu_name) {
-      menu_cache_clear($this->original->menu_name);
+    menu_cache_clear($this->menu_name->value);
+    if (isset($this->original) && $this->menu_name->value != $this->original->menu_name->value) {
+      menu_cache_clear($this->original->menu_name->value);
     }
 
     // Now clear the cache.
@@ -528,41 +646,41 @@ public static function findRouteName($link_path) {
    */
   public function setParents(EntityInterface $parent) {
     $i = 1;
-    while ($i < $this->depth) {
+    while ($i < $this->depth->value) {
       $p = 'p' . $i++;
-      $this->{$p} = $parent->{$p};
+      $this->{$p}->value = $parent->{$p}->value;
     }
     $p = 'p' . $i++;
     // The parent (p1 - p9) corresponding to the depth always equals the mlid.
-    $this->{$p} = $this->id();
+    $this->{$p}->value = $this->id();
     while ($i <= MENU_MAX_DEPTH) {
       $p = 'p' . $i++;
-      $this->{$p} = 0;
+      $this->{$p}->value = 0;
     }
   }
 
   /**
    * {@inheritdoc}
    */
-  public function findParent(EntityStorageControllerInterface $storage_controller, array $parent_candidates = array()) {
+  public function findParent(MenuLinkStorageControllerInterface $storage_controller, array $parent_candidates = array()) {
     $parent = FALSE;
 
     // This item is explicitely top-level, skip the rest of the parenting.
-    if (isset($this->plid) && empty($this->plid)) {
+    if (isset($this->plid->target_id) && empty($this->plid->target_id)) {
       return $parent;
     }
 
     // If we have a parent link ID, try to use that.
     $candidates = array();
-    if (isset($this->plid)) {
-      $candidates[] = $this->plid;
+    if (isset($this->plid->target_id)) {
+      $candidates[] = $this->plid->target_id;
     }
 
     // Else, if we have a link hierarchy try to find a valid parent in there.
-    if (!empty($this->depth) && $this->depth > 1) {
-      for ($depth = $this->depth - 1; $depth >= 1; $depth--) {
+    if (!empty($this->depth->value) && $this->depth->value > 1) {
+      for ($depth = $this->depth->value - 1; $depth >= 1; $depth--) {
         $parent_property = "p$depth";
-        $candidates[] = $this->$parent_property;
+        $candidates[] = $this->$parent_property->value;
       }
     }
 
@@ -581,12 +699,11 @@ public function findParent(EntityStorageControllerInterface $storage_controller,
     // If everything else failed, try to derive the parent from the path
     // hierarchy. This only makes sense for links derived from menu router
     // items (ie. from hook_menu()).
-    if ($this->module == 'system') {
+    if ($this->module->value == 'system') {
       $parent = $storage_controller->getParentFromHierarchy($this);
     }
 
     return $parent;
   }
 
-
 }
diff --git a/core/modules/shortcut/shortcut.module b/core/modules/shortcut/shortcut.module
index c22c97f..514f1d1 100644
--- a/core/modules/shortcut/shortcut.module
+++ b/core/modules/shortcut/shortcut.module
@@ -55,7 +55,7 @@ function shortcut_entity_bundle_info() {
 function shortcut_menu_link_load($entities) {
   foreach ($entities as $entity) {
     // Change the bundle of menu links related to a shortcut.
-    if (strpos($entity->menu_name, 'shortcut-') === 0) {
+    if (strpos($entity->menu_name->value, 'shortcut-') === 0) {
       $entity->bundle = 'shortcut';
     }
   }