diff --git a/core/includes/batch.queue.inc b/core/includes/batch.queue.inc
deleted file mode 100644
index ed290ee..0000000
--- a/core/includes/batch.queue.inc
+++ /dev/null
@@ -1,84 +0,0 @@
-<?php
-
-/**
- * @file
- * Queue handlers used by the Batch API.
- *
- * These implementations:
- * - Ensure FIFO ordering.
- * - Allow an item to be repeatedly claimed until it is actually deleted (no
- *   notion of lease time or 'expire' date), to allow multipass operations.
- */
-
-/**
- * Defines a batch queue.
- *
- * Stale items from failed batches are cleaned from the {queue} table on cron
- * using the 'created' date.
- */
-class BatchQueue extends SystemQueue {
-
-  /**
-   * Overrides SystemQueue::claimItem().
-   *
-   * Unlike SystemQueue::claimItem(), this method provides a default lease
-   * time of 0 (no expiration) instead of 30. This allows the item to be
-   * claimed repeatedly until it is deleted.
-   */
-  public function claimItem($lease_time = 0) {
-    $item = db_query_range('SELECT data, item_id FROM {queue} q WHERE name = :name ORDER BY item_id ASC', 0, 1, array(':name' => $this->name))->fetchObject();
-    if ($item) {
-      $item->data = unserialize($item->data);
-      return $item;
-    }
-    return FALSE;
-  }
-
-  /**
-   * Retrieves all remaining items in the queue.
-   *
-   * This is specific to Batch API and is not part of the DrupalQueueInterface.
-   */
-  public function getAllItems() {
-    $result = array();
-    $items = db_query('SELECT data FROM {queue} q WHERE name = :name ORDER BY item_id ASC', array(':name' => $this->name))->fetchAll();
-    foreach ($items as $item) {
-      $result[] = unserialize($item->data);
-    }
-    return $result;
-  }
-}
-
-/**
- * Defines a batch queue for non-progressive batches.
- */
-class BatchMemoryQueue extends MemoryQueue {
-
-  /**
-   * Overrides MemoryQueue::claimItem().
-   *
-   * Unlike MemoryQueue::claimItem(), this method provides a default lease
-   * time of 0 (no expiration) instead of 30. This allows the item to be
-   * claimed repeatedly until it is deleted.
-   */
-  public function claimItem($lease_time = 0) {
-    if (!empty($this->queue)) {
-      reset($this->queue);
-      return current($this->queue);
-    }
-    return FALSE;
-  }
-
-  /**
-   * Retrieves all remaining items in the queue.
-   *
-   * This is specific to Batch API and is not part of the DrupalQueueInterface.
-   */
-  public function getAllItems() {
-    $result = array();
-    foreach ($this->queue as $item) {
-      $result[] = $item->data;
-    }
-    return $result;
-  }
-}
diff --git a/core/includes/common.inc b/core/includes/common.inc
index 46caf3e..b4289ed 100644
--- a/core/includes/common.inc
+++ b/core/includes/common.inc
@@ -5248,7 +5248,7 @@ function drupal_cron_run() {
     // Make sure every queue exists. There is no harm in trying to recreate an
     // existing queue.
     foreach ($queues as $queue_name => $info) {
-      DrupalQueue::get($queue_name)->createQueue();
+      queue($queue_name)->createQueue();
     }
     // Register shutdown callback.
     drupal_register_shutdown_function('drupal_cron_cleanup');
@@ -5278,7 +5278,7 @@ function drupal_cron_run() {
   foreach ($queues as $queue_name => $info) {
     $function = $info['worker callback'];
     $end = time() + (isset($info['time']) ? $info['time'] : 15);
-    $queue = DrupalQueue::get($queue_name);
+    $queue = queue($queue_name);
     while (time() < $end && ($item = $queue->claimItem())) {
       $function($item->data);
       $queue->deleteItem($item);
@@ -7843,3 +7843,97 @@ function drupal_get_filetransfer_info() {
   }
   return $info;
 }
+
+/**
+ * @defgroup queue Queue operations
+ * @{
+ * Queue items to allow later processing.
+ *
+ * The queue system allows placing items in a queue and processing them later.
+ * The system tries to ensure that only one consumer can process an item.
+ *
+ * Before a queue can be used it needs to be created by
+ * Drupal\Core\Queue\QueueInterface::createQueue().
+ *
+ * Items can be added to the queue by passing an arbitrary data object to
+ * Drupal\Core\Queue\QueueInterface::createItem().
+ *
+ * To process an item, call Drupal\Core\Queue\QueueInterface::claimItem() and
+ * specify how long you want to have a lease for working on that item.
+ * When finished processing, the item needs to be deleted by calling
+ * Drupal\Core\Queue\QueueInterface::deleteItem(). If the consumer dies, the
+ * item will be made available again by the Drupal\Core\Queue\QueueInterface
+ * implementation once the lease expires. Another consumer will then be able to
+ * receive it when calling Drupal\Core\Queue\QueueInterface::claimItem().
+ * Due to this, the processing code should be aware that an item might be handed
+ * over for processing more than once.
+ *
+ * The $item object used by the Drupal\Core\Queue\QueueInterface can contain
+ * arbitrary metadata depending on the implementation. Systems using the
+ * interface should only rely on the data property which will contain the
+ * information passed to Drupal\Core\Queue\QueueInterface::createItem().
+ * The full queue item returned by Drupal\Core\Queue\QueueInterface::claimItem()
+ * needs to be passed to Drupal\Core\Queue\QueueInterface::deleteItem() once
+ * processing is completed.
+ *
+ * There are two kinds of queue backends available: reliable, which preserves
+ * the order of messages and guarantees that every item will be executed at
+ * least once. The non-reliable kind only does a best effort to preserve order
+ * in messages and to execute them at least once but there is a small chance
+ * that some items get lost. For example, some distributed back-ends like
+ * Amazon SQS will be managing jobs for a large set of producers and consumers
+ * where a strict FIFO ordering will likely not be preserved. Another example
+ * would be an in-memory queue backend which might lose items if it crashes.
+ * However, such a backend would be able to deal with significantly more writes
+ * than a reliable queue and for many tasks this is more important. See
+ * aggregator_cron() for an example of how to effectively utilize a
+ * non-reliable queue. Another example is doing Twitter statistics -- the small
+ * possibility of losing a few items is insignificant next to power of the
+ * queue being able to keep up with writes. As described in the processing
+ * section, regardless of the queue being reliable or not, the processing code
+ * should be aware that an item might be handed over for processing more than
+ * once (because the processing code might time out before it finishes).
+ */
+
+/**
+ * Instantiates and statically caches the correct class for a queue.
+ *
+ * The following variables can be set by variable_set or $conf overrides:
+ * - queue_class_$name: the class to be used for the queue $name.
+ * - queue_default_class: the class to use when queue_class_$name is not
+ *   defined. Defaults to Drupal\Core\Queue\System, a reliable backend using
+ *   SQL.
+ * - queue_default_reliable_class: the class to use when queue_class_$name is
+ *   not defined and the queue_default_class is not reliable. Defaults to
+ *   Drupal\Core\Queue\System.
+ *
+ * @param string $name
+ *   The name of the queue to work with.
+ * @param bool $reliable
+ *   TRUE if the ordering of items and guaranteeing every item executes at
+ *   least once is important, FALSE if scalability is the main concern. Defaults
+ *   to FALSE.
+ *
+ * @return Drupal\Core\Queue\QueueInterface
+ *   The queue object for a given name.
+ *
+ * @see Drupal\Core\Queue\QueueInterface
+ */
+function queue($name, $reliable = FALSE) {
+  static $queues;
+  if (!isset($queues[$name])) {
+    $class = variable_get('queue_class_' . $name, NULL);
+    if ($class && $reliable && in_array('ReliableQueueInterface', class_implements($class))) {
+      $class = variable_get('queue_default_reliable_class', 'Drupal\Core\Queue\System');
+    }
+    elseif (!$class) {
+      $class = variable_get('queue_default_class', 'Drupal\Core\Queue\System');
+    }
+    $queues[$name] = new $class($name);
+  }
+  return $queues[$name];
+}
+
+/**
+ * @} End of "defgroup queue".
+ */
diff --git a/core/includes/form.inc b/core/includes/form.inc
index 0124abc..e0fe9d1 100644
--- a/core/includes/form.inc
+++ b/core/includes/form.inc
@@ -4533,8 +4533,9 @@ function &batch_get() {
 /**
  * Populates a job queue with the operations of a batch set.
  *
- * Depending on whether the batch is progressive or not, the BatchQueue or
- * BatchMemoryQueue handler classes will be used.
+ * Depending on whether the batch is progressive or not, the
+ * Drupal\Core\Queue\Batch or Drupal\Core\Queue\BatchMemory handler classes will
+ * be used.
  *
  * @param $batch
  *   The batch array.
@@ -4551,7 +4552,7 @@ function _batch_populate_queue(&$batch, $set_id) {
     $batch_set += array(
       'queue' => array(
         'name' => 'drupal_batch:' . $batch['id'] . ':' . $set_id,
-        'class' => $batch['progressive'] ? 'BatchQueue' : 'BatchMemoryQueue',
+        'class' => $batch['progressive'] ? 'Drupal\Core\Queue\Batch' : 'Drupal\Core\Queue\BatchMemory',
       ),
     );
 
@@ -4577,12 +4578,8 @@ function _batch_populate_queue(&$batch, $set_id) {
 function _batch_queue($batch_set) {
   static $queues;
 
-  // The class autoloader is not available when running update.php, so make
-  // sure the files are manually included.
   if (!isset($queues)) {
     $queues = array();
-    require_once DRUPAL_ROOT . '/core/modules/system/system.queue.inc';
-    require_once DRUPAL_ROOT . '/core/includes/batch.queue.inc';
   }
 
   if (isset($batch_set['queue'])) {
diff --git a/core/lib/Drupal/Core/Queue/Batch.php b/core/lib/Drupal/Core/Queue/Batch.php
new file mode 100644
index 0000000..a1de48a
--- /dev/null
+++ b/core/lib/Drupal/Core/Queue/Batch.php
@@ -0,0 +1,56 @@
+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Queue\Batch.
+ */
+
+namespace Drupal\Core\Queue;
+
+/**
+ * Defines a batch queue handler used by the Batch API.
+ *
+ * This implementation:
+ * - Ensures FIFO ordering.
+ * - Allows an item to be repeatedly claimed until it is actually deleted (no
+ *   notion of lease time or 'expire' date), to allow multipass operations.
+ *
+ * Stale items from failed batches are cleaned from the {queue} table on cron
+ * using the 'created' date.
+ */
+class Batch extends System {
+
+  /**
+   * Overrides Drupal\Core\Queue\System::claimItem().
+   *
+   * Unlike Drupal\Core\Queue\System::claimItem(), this method provides a
+   * default lease time of 0 (no expiration) instead of 30. This allows the item
+   * to be claimed repeatedly until it is deleted.
+   */
+  public function claimItem($lease_time = 0) {
+    $item = db_query_range('SELECT data, item_id FROM {queue} q WHERE name = :name ORDER BY item_id ASC', 0, 1, array(':name' => $this->name))->fetchObject();
+    if ($item) {
+      $item->data = unserialize($item->data);
+      return $item;
+    }
+    return FALSE;
+  }
+
+  /**
+   * Retrieves all remaining items in the queue.
+   *
+   * This is specific to Batch API and is not part of the
+   * Drupal\Core\Queue\QueueInterface.
+   *
+   * @return array
+   *   An array of queue items.
+   */
+  public function getAllItems() {
+    $result = array();
+    $items = db_query('SELECT data FROM {queue} q WHERE name = :name ORDER BY item_id ASC', array(':name' => $this->name))->fetchAll();
+    foreach ($items as $item) {
+      $result[] = unserialize($item->data);
+    }
+    return $result;
+  }
+}
diff --git a/core/lib/Drupal/Core/Queue/BatchMemory.php b/core/lib/Drupal/Core/Queue/BatchMemory.php
new file mode 100644
index 0000000..fcc49f5
--- /dev/null
+++ b/core/lib/Drupal/Core/Queue/BatchMemory.php
@@ -0,0 +1,52 @@
+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Queue\BatchMemory.
+ */
+
+namespace Drupal\Core\Queue;
+
+/**
+ * Defines a batch queue handler used by the Batch API for non-progressive
+ * batches.
+ *
+ * This implementation:
+ * - Ensures FIFO ordering.
+ * - Allows an item to be repeatedly claimed until it is actually deleted (no
+ *   notion of lease time or 'expire' date), to allow multipass operations.
+ */
+class BatchMemory extends Memory {
+
+  /**
+   * Overrides Drupal\Core\Queue\Memory::claimItem().
+   *
+   * Unlike Drupal\Core\Queue\Memory::claimItem(), this method provides a
+   * default lease time of 0 (no expiration) instead of 30. This allows the item
+   * to be claimed repeatedly until it is deleted.
+   */
+  public function claimItem($lease_time = 0) {
+    if (!empty($this->queue)) {
+      reset($this->queue);
+      return current($this->queue);
+    }
+    return FALSE;
+  }
+
+  /**
+   * Retrieves all remaining items in the queue.
+   *
+   * This is specific to Batch API and is not part of the
+   * Drupal\Core\Queue\QueueInterface.
+   *
+   * @return array
+   *   An array of queue items.
+   */
+  public function getAllItems() {
+    $result = array();
+    foreach ($this->queue as $item) {
+      $result[] = $item->data;
+    }
+    return $result;
+  }
+}
diff --git a/core/lib/Drupal/Core/Queue/Memory.php b/core/lib/Drupal/Core/Queue/Memory.php
new file mode 100644
index 0000000..f5df5c5
--- /dev/null
+++ b/core/lib/Drupal/Core/Queue/Memory.php
@@ -0,0 +1,107 @@
+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Queue\Memory.
+ */
+
+namespace Drupal\Core\Queue;
+
+use stdClass;
+
+/**
+ * Static queue implementation.
+ *
+ * This allows "undelayed" variants of processes relying on the Queue
+ * interface. The queue data resides in memory. It should only be used for
+ * items that will be queued and dequeued within a given page request.
+ */
+class Memory implements QueueInterface {
+  /**
+   * The queue data.
+   *
+   * @var array
+   */
+  protected $queue;
+
+  /**
+   * Counter for item ids.
+   *
+   * @var int
+   */
+  protected $id_sequence;
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::__construct().
+   */
+  public function __construct($name) {
+    $this->queue = array();
+    $this->id_sequence = 0;
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::createItem().
+   */
+  public function createItem($data) {
+    $item = new stdClass();
+    $item->item_id = $this->id_sequence++;
+    $item->data = $data;
+    $item->created = time();
+    $item->expire = 0;
+    $this->queue[$item->item_id] = $item;
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::numberOfItems().
+   */
+  public function numberOfItems() {
+    return count($this->queue);
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::claimItem().
+   */
+  public function claimItem($lease_time = 30) {
+    foreach ($this->queue as $key => $item) {
+      if ($item->expire == 0) {
+        $item->expire = time() + $lease_time;
+        $this->queue[$key] = $item;
+        return $item;
+      }
+    }
+    return FALSE;
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::deleteItem().
+   */
+  public function deleteItem($item) {
+    unset($this->queue[$item->item_id]);
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::releaseItem().
+   */
+  public function releaseItem($item) {
+    if (isset($this->queue[$item->item_id]) && $this->queue[$item->item_id]->expire != 0) {
+      $this->queue[$item->item_id]->expire = 0;
+      return TRUE;
+    }
+    return FALSE;
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::createQueue().
+   */
+  public function createQueue() {
+    // Nothing needed here.
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::deleteQueue().
+   */
+  public function deleteQueue() {
+    $this->queue = array();
+    $this->id_sequence = 0;
+  }
+}
diff --git a/core/lib/Drupal/Core/Queue/QueueInterface.php b/core/lib/Drupal/Core/Queue/QueueInterface.php
new file mode 100644
index 0000000..90d4b00
--- /dev/null
+++ b/core/lib/Drupal/Core/Queue/QueueInterface.php
@@ -0,0 +1,114 @@
+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Queue\QueueInterface.
+ */
+
+namespace Drupal\Core\Queue;
+
+/**
+ * Interface for a queue.
+ *
+ * Classes implementing this interface will do a best effort to preserve order
+ * in messages and to execute them at least once.
+ */
+interface QueueInterface {
+  /**
+   * Start working with a queue.
+   *
+   * @param $name
+   *   Arbitrary string. The name of the queue to work with.
+   */
+  public function __construct($name);
+
+  /**
+   * Adds a queue item and store it directly to the queue.
+   *
+   * @param $data
+   *   Arbitrary data to be associated with the new task in the queue.
+   *
+   * @return
+   *   TRUE if the item was successfully created and was (best effort) added
+   *   to the queue, otherwise FALSE. We don't guarantee the item was
+   *   committed to disk etc, but as far as we know, the item is now in the
+   *   queue.
+   */
+  public function createItem($data);
+
+  /**
+   * Retrieves the number of items in the queue.
+   *
+   * This is intended to provide a "best guess" count of the number of items in
+   * the queue. Depending on the implementation and the setup, the accuracy of
+   * the results of this function may vary.
+   *
+   * e.g. On a busy system with a large number of consumers and items, the
+   * result might only be valid for a fraction of a second and not provide an
+   * accurate representation.
+   *
+   * @return
+   *   An integer estimate of the number of items in the queue.
+   */
+  public function numberOfItems();
+
+  /**
+   * Claims an item in the queue for processing.
+   *
+   * @param $lease_time
+   *   How long the processing is expected to take in seconds, defaults to an
+   *   hour. After this lease expires, the item will be reset and another
+   *   consumer can claim the item. For idempotent tasks (which can be run
+   *   multiple times without side effects), shorter lease times would result
+   *   in lower latency in case a consumer fails. For tasks that should not be
+   *   run more than once (non-idempotent), a larger lease time will make it
+   *   more rare for a given task to run multiple times in cases of failure,
+   *   at the cost of higher latency.
+   *
+   * @return
+   *   On success we return an item object. If the queue is unable to claim an
+   *   item it returns false. This implies a best effort to retrieve an item
+   *   and either the queue is empty or there is some other non-recoverable
+   *   problem.
+   */
+  public function claimItem($lease_time = 3600);
+
+  /**
+   * Deletes a finished item from the queue.
+   *
+   * @param $item
+   *   The item returned by Drupal\Core\Queue\QueueInterface::claimItem().
+   */
+  public function deleteItem($item);
+
+  /**
+   * Releases an item that the worker could not process.
+   *
+   * Another worker can come in and process it before the timeout expires.
+   *
+   * @param $item
+   *   The item returned by Drupal\Core\Queue\QueueInterface::claimItem().
+   *
+   * @return boolean
+   *   TRUE if the item has been released, FALSE otherwise.
+   */
+  public function releaseItem($item);
+
+  /**
+   * Creates a queue.
+   *
+   * Called during installation and should be used to perform any necessary
+   * initialization operations. This should not be confused with the
+   * constructor for these objects, which is called every time an object is
+   * instantiated to operate on a queue. This operation is only needed the
+   * first time a given queue is going to be initialized (for example, to make
+   * a new database table or directory to hold tasks for the queue -- it
+   * depends on the queue implementation if this is necessary at all).
+   */
+  public function createQueue();
+
+  /**
+   * Deletes a queue and every item in the queue.
+   */
+  public function deleteQueue();
+}
diff --git a/core/lib/Drupal/Core/Queue/ReliableQueueInterface.php b/core/lib/Drupal/Core/Queue/ReliableQueueInterface.php
new file mode 100644
index 0000000..7f7f8b2
--- /dev/null
+++ b/core/lib/Drupal/Core/Queue/ReliableQueueInterface.php
@@ -0,0 +1,17 @@
+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Queue\ReliableQueueInterface.
+ */
+
+namespace Drupal\Core\Queue;
+
+/**
+ * Reliable queue interface.
+ *
+ * Classes implementing this interface preserve the order of messages and
+ * guarantee that every item will be executed at least once.
+ */
+interface ReliableQueueInterface extends QueueInterface {
+}
diff --git a/core/lib/Drupal/Core/Queue/System.php b/core/lib/Drupal/Core/Queue/System.php
new file mode 100644
index 0000000..6deab47
--- /dev/null
+++ b/core/lib/Drupal/Core/Queue/System.php
@@ -0,0 +1,126 @@
+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Queue\System.
+ */
+
+namespace Drupal\Core\Queue;
+
+/**
+ * Default queue implementation.
+ */
+class System implements ReliableQueueInterface {
+  /**
+   * The name of the queue this instance is working with.
+   *
+   * @var string
+   */
+  protected $name;
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::__construct().
+   */
+  public function __construct($name) {
+    $this->name = $name;
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::createItem().
+   */
+  public function createItem($data) {
+    // During a Drupal 6.x to 8.x update, drupal_get_schema() does not contain
+    // the queue table yet, so we cannot rely on drupal_write_record().
+    $query = db_insert('queue')
+      ->fields(array(
+        'name' => $this->name,
+        'data' => serialize($data),
+        // We cannot rely on REQUEST_TIME because many items might be created
+        // by a single request which takes longer than 1 second.
+        'created' => time(),
+      ));
+    return (bool) $query->execute();
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::numberOfItems().
+   */
+  public function numberOfItems() {
+    return db_query('SELECT COUNT(item_id) FROM {queue} WHERE name = :name', array(':name' => $this->name))->fetchField();
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::claimItem().
+   */
+  public function claimItem($lease_time = 30) {
+    // Claim an item by updating its expire fields. If claim is not successful
+    // another thread may have claimed the item in the meantime. Therefore loop
+    // until an item is successfully claimed or we are reasonably sure there
+    // are no unclaimed items left.
+    while (TRUE) {
+      $item = db_query_range('SELECT data, item_id FROM {queue} q WHERE expire = 0 AND name = :name ORDER BY created ASC', 0, 1, array(':name' => $this->name))->fetchObject();
+      if ($item) {
+        // Try to update the item. Only one thread can succeed in UPDATEing the
+        // same row. We cannot rely on REQUEST_TIME because items might be
+        // claimed by a single consumer which runs longer than 1 second. If we
+        // continue to use REQUEST_TIME instead of the current time(), we steal
+        // time from the lease, and will tend to reset items before the lease
+        // should really expire.
+        $update = db_update('queue')
+          ->fields(array(
+            'expire' => time() + $lease_time,
+          ))
+          ->condition('item_id', $item->item_id)
+          ->condition('expire', 0);
+        // If there are affected rows, this update succeeded.
+        if ($update->execute()) {
+          $item->data = unserialize($item->data);
+          return $item;
+        }
+      }
+      else {
+        // No items currently available to claim.
+        return FALSE;
+      }
+    }
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::releaseItem().
+   */
+  public function releaseItem($item) {
+    $update = db_update('queue')
+      ->fields(array(
+        'expire' => 0,
+      ))
+      ->condition('item_id', $item->item_id);
+      return $update->execute();
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::deleteItem().
+   */
+  public function deleteItem($item) {
+    db_delete('queue')
+      ->condition('item_id', $item->item_id)
+      ->execute();
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::createQueue().
+   */
+  public function createQueue() {
+    // All tasks are stored in a single database table (which is created when
+    // Drupal is first installed) so there is nothing we need to do to create
+    // a new queue.
+  }
+
+  /**
+   * Implements Drupal\Core\Queue\QueueInterface::deleteQueue().
+   */
+  public function deleteQueue() {
+    db_delete('queue')
+      ->condition('name', $this->name)
+      ->execute();
+  }
+}
diff --git a/core/modules/aggregator/aggregator.module b/core/modules/aggregator/aggregator.module
index 7b65dfa..b4ffa8c 100644
--- a/core/modules/aggregator/aggregator.module
+++ b/core/modules/aggregator/aggregator.module
@@ -313,7 +313,7 @@ function aggregator_cron() {
     ':time' => REQUEST_TIME,
     ':never' => AGGREGATOR_CLEAR_NEVER
   ));
-  $queue = DrupalQueue::get('aggregator_feeds');
+  $queue = queue('aggregator_feeds');
   foreach ($result as $feed) {
     if ($queue->createItem($feed)) {
       // Add timestamp to avoid queueing item more than once.
diff --git a/core/modules/simpletest/simpletest.info b/core/modules/simpletest/simpletest.info
index d518a76..7201608 100644
--- a/core/modules/simpletest/simpletest.info
+++ b/core/modules/simpletest/simpletest.info
@@ -29,6 +29,7 @@ files[] = tests/module.test
 files[] = tests/pager.test
 files[] = tests/password.test
 files[] = tests/path.test
+files[] = tests/queue.test
 files[] = tests/registry.test
 files[] = tests/schema.test
 files[] = tests/session.test
diff --git a/core/modules/simpletest/tests/queue.test b/core/modules/simpletest/tests/queue.test
new file mode 100644
index 0000000..8ed251c
--- /dev/null
+++ b/core/modules/simpletest/tests/queue.test
@@ -0,0 +1,120 @@
+<?php
+
+use Drupal\Core\Queue\Memory;
+use Drupal\Core\Queue\System;
+
+/**
+ * Tests the basic queue functionality.
+ */
+class QueueTestCase extends DrupalWebTestCase {
+  public static function getInfo() {
+    return array(
+      'name' => 'Queue functionality',
+      'description' => 'Queues and dequeues a set of items to check the basic queue functionality.',
+      'group' => 'Queue',
+    );
+  }
+
+  /**
+   * Tests the System queue.
+   */
+  function testSystemQueue() {
+    // Create two queues.
+    $queue1 = new System($this->randomName());
+    $queue1->createQueue();
+    $queue2 = new System($this->randomName());
+    $queue2->createQueue();
+
+    $this->queueTest($queue1, $queue2);
+  }
+
+  /**
+   * Tests the Memory queue.
+   */
+  function testMemoryQueue() {
+    // Create two queues.
+    $queue1 = new Memory($this->randomName());
+    $queue1->createQueue();
+    $queue2 = new Memory($this->randomName());
+    $queue2->createQueue();
+
+    $this->queueTest($queue1, $queue2);
+  }
+
+  /**
+   * Queues and dequeues a set of items to check the basic queue functionality.
+   *
+   * @param Drupal\Core\Queue\QueueInterface $queue1
+   *   An instantiated queue object.
+   * @param Drupal\Core\Queue\QueueInterface $queue2
+   *   An instantiated queue object.
+   */
+  function queueTest($queue1, $queue2) {
+    // Create four items.
+    $data = array();
+    for ($i = 0; $i < 4; $i++) {
+      $data[] = array($this->randomName() => $this->randomName());
+    }
+
+    // Queue items 1 and 2 in the queue1.
+    $queue1->createItem($data[0]);
+    $queue1->createItem($data[1]);
+
+    // Retrieve two items from queue1.
+    $items = array();
+    $new_items = array();
+
+    $items[] = $item = $queue1->claimItem();
+    $new_items[] = $item->data;
+
+    $items[] = $item = $queue1->claimItem();
+    $new_items[] = $item->data;
+
+    // First two dequeued items should match the first two items we queued.
+    $this->assertEqual($this->queueScore($data, $new_items), 2, t('Two items matched'));
+
+    // Add two more items.
+    $queue1->createItem($data[2]);
+    $queue1->createItem($data[3]);
+
+    $this->assertTrue($queue1->numberOfItems(), t('Queue 1 is not empty after adding items.'));
+    $this->assertFalse($queue2->numberOfItems(), t('Queue 2 is empty while Queue 1 has items'));
+
+    $items[] = $item = $queue1->claimItem();
+    $new_items[] = $item->data;
+
+    $items[] = $item = $queue1->claimItem();
+    $new_items[] = $item->data;
+
+    // All dequeued items should match the items we queued exactly once,
+    // therefore the score must be exactly 4.
+    $this->assertEqual($this->queueScore($data, $new_items), 4, t('Four items matched'));
+
+    // There should be no duplicate items.
+    $this->assertEqual($this->queueScore($new_items, $new_items), 4, t('Four items matched'));
+
+    // Delete all items from queue1.
+    foreach ($items as $item) {
+      $queue1->deleteItem($item);
+    }
+
+    // Check that both queues are empty.
+    $this->assertFalse($queue1->numberOfItems(), t('Queue 1 is empty'));
+    $this->assertFalse($queue2->numberOfItems(), t('Queue 2 is empty'));
+  }
+
+  /**
+   * Returns the number of equal items in two arrays.
+   */
+  function queueScore($items, $new_items) {
+    $score = 0;
+    foreach ($items as $item) {
+      foreach ($new_items as $new_item) {
+        if ($item === $new_item) {
+          $score++;
+        }
+      }
+    }
+    return $score;
+  }
+}
diff --git a/core/modules/system/system.api.php b/core/modules/system/system.api.php
index 907b7b5..a248786 100644
--- a/core/modules/system/system.api.php
+++ b/core/modules/system/system.api.php
@@ -138,7 +138,7 @@ function hook_cron() {
     ':time' => REQUEST_TIME,
     ':never' => AGGREGATOR_CLEAR_NEVER,
   ));
-  $queue = DrupalQueue::get('aggregator_feeds');
+  $queue = queue('aggregator_feeds');
   foreach ($result as $feed) {
     $queue->createItem($feed);
   }
@@ -158,8 +158,8 @@ function hook_cron() {
  *   An associative array where the key is the queue name and the value is
  *   again an associative array. Possible keys are:
  *   - 'worker callback': The name of the function to call. It will be called
- *     with one argument, the item created via DrupalQueue::createItem() in
- *     hook_cron().
+ *     with one argument, the item created via
+ *     Drupal\Core\Queue\QueueInterface::createItem() in hook_cron().
  *   - 'time': (optional) How much time Drupal should spend on calling this
  *     worker in seconds. Defaults to 15.
  *
diff --git a/core/modules/system/system.info b/core/modules/system/system.info
index c394849..a150120 100644
--- a/core/modules/system/system.info
+++ b/core/modules/system/system.info
@@ -5,7 +5,6 @@ version = VERSION
 core = 8.x
 files[] = system.archiver.inc
 files[] = system.mail.inc
-files[] = system.queue.inc
 files[] = system.tar.inc
 files[] = system.updater.inc
 files[] = system.test
diff --git a/core/modules/system/system.queue.inc b/core/modules/system/system.queue.inc
deleted file mode 100644
index c2a6b13..0000000
--- a/core/modules/system/system.queue.inc
+++ /dev/null
@@ -1,371 +0,0 @@
-<?php
-
-/**
- * @file
- * Queue functionality.
- */
-
-/**
- * @defgroup queue Queue operations
- * @{
- * Queue items to allow later processing.
- *
- * The queue system allows placing items in a queue and processing them later.
- * The system tries to ensure that only one consumer can process an item.
- *
- * Before a queue can be used it needs to be created by
- * DrupalQueueInterface::createQueue().
- *
- * Items can be added to the queue by passing an arbitrary data object to
- * DrupalQueueInterface::createItem().
- *
- * To process an item, call DrupalQueueInterface::claimItem() and specify how
- * long you want to have a lease for working on that item. When finished
- * processing, the item needs to be deleted by calling
- * DrupalQueueInterface::deleteItem(). If the consumer dies, the item will be
- * made available again by the DrupalQueueInterface implementation once the
- * lease expires. Another consumer will then be able to receive it when calling
- * DrupalQueueInterface::claimItem(). Due to this, the processing code should
- * be aware that an item might be handed over for processing more than once.
- *
- * The $item object used by the DrupalQueueInterface can contain arbitrary
- * metadata depending on the implementation. Systems using the interface should
- * only rely on the data property which will contain the information passed to
- * DrupalQueueInterface::createItem(). The full queue item returned by
- * DrupalQueueInterface::claimItem() needs to be passed to
- * DrupalQueueInterface::deleteItem() once processing is completed.
- *
- * There are two kinds of queue backends available: reliable, which preserves
- * the order of messages and guarantees that every item will be executed at
- * least once. The non-reliable kind only does a best effort to preserve order
- * in messages and to execute them at least once but there is a small chance
- * that some items get lost. For example, some distributed back-ends like
- * Amazon SQS will be managing jobs for a large set of producers and consumers
- * where a strict FIFO ordering will likely not be preserved. Another example
- * would be an in-memory queue backend which might lose items if it crashes.
- * However, such a backend would be able to deal with significantly more writes
- * than a reliable queue and for many tasks this is more important. See
- * aggregator_cron() for an example of how to effectively utilize a
- * non-reliable queue. Another example is doing Twitter statistics -- the small
- * possibility of losing a few items is insignificant next to power of the
- * queue being able to keep up with writes. As described in the processing
- * section, regardless of the queue being reliable or not, the processing code
- * should be aware that an item might be handed over for processing more than
- * once (because the processing code might time out before it finishes).
- */
-
-/**
- * Factory class for interacting with queues.
- */
-class DrupalQueue {
-  /**
-   * Returns the queue object for a given name.
-   *
-   * The following variables can be set by variable_set or $conf overrides:
-   * - queue_class_$name: the class to be used for the queue $name.
-   * - queue_default_class: the class to use when queue_class_$name is not
-   *   defined. Defaults to SystemQueue, a reliable backend using SQL.
-   * - queue_default_reliable_class: the class to use when queue_class_$name is
-   *   not defined and the queue_default_class is not reliable. Defaults to
-   *   SystemQueue.
-   *
-   * @param $name
-   *   Arbitrary string. The name of the queue to work with.
-   * @param $reliable
-   *   TRUE if the ordering of items and guaranteeing every item executes at
-   *   least once is important, FALSE if scalability is the main concern.
-   *
-   * @return
-   *   The queue object for a given name.
-   */
-  public static function get($name, $reliable = FALSE) {
-    static $queues;
-    if (!isset($queues[$name])) {
-      $class = variable_get('queue_class_' . $name, NULL);
-      if (!$class) {
-        $class = variable_get('queue_default_class', 'SystemQueue');
-      }
-      $object = new $class($name);
-      if ($reliable && !$object instanceof DrupalReliableQueueInterface) {
-        $class = variable_get('queue_default_reliable_class', 'SystemQueue');
-        $object = new $class($name);
-      }
-      $queues[$name] = $object;
-    }
-    return $queues[$name];
-  }
-}
-
-interface DrupalQueueInterface {
-  /**
-   * Start working with a queue.
-   *
-   * @param $name
-   *   Arbitrary string. The name of the queue to work with.
-   */
-  public function __construct($name);
-
-  /**
-   * Add a queue item and store it directly to the queue.
-   *
-   * @param $data
-   *   Arbitrary data to be associated with the new task in the queue.
-   * @return
-   *   TRUE if the item was successfully created and was (best effort) added
-   *   to the queue, otherwise FALSE. We don't guarantee the item was
-   *   committed to disk etc, but as far as we know, the item is now in the
-   *   queue.
-   */
-  public function createItem($data);
-
-  /**
-   * Retrieve the number of items in the queue.
-   *
-   * This is intended to provide a "best guess" count of the number of items in
-   * the queue. Depending on the implementation and the setup, the accuracy of
-   * the results of this function may vary.
-   *
-   * e.g. On a busy system with a large number of consumers and items, the
-   * result might only be valid for a fraction of a second and not provide an
-   * accurate representation.
-   *
-   * @return
-   *   An integer estimate of the number of items in the queue.
-   */
-  public function numberOfItems();
-
-  /**
-   * Claim an item in the queue for processing.
-   *
-   * @param $lease_time
-   *   How long the processing is expected to take in seconds, defaults to an
-   *   hour. After this lease expires, the item will be reset and another
-   *   consumer can claim the item. For idempotent tasks (which can be run
-   *   multiple times without side effects), shorter lease times would result
-   *   in lower latency in case a consumer fails. For tasks that should not be
-   *   run more than once (non-idempotent), a larger lease time will make it
-   *   more rare for a given task to run multiple times in cases of failure,
-   *   at the cost of higher latency.
-   * @return
-   *   On success we return an item object. If the queue is unable to claim an
-   *   item it returns false. This implies a best effort to retrieve an item
-   *   and either the queue is empty or there is some other non-recoverable
-   *   problem.
-   */
-  public function claimItem($lease_time = 3600);
-
-  /**
-   * Delete a finished item from the queue.
-   *
-   * @param $item
-   *   The item returned by DrupalQueueInterface::claimItem().
-   */
-  public function deleteItem($item);
-
-  /**
-   * Release an item that the worker could not process, so another
-   * worker can come in and process it before the timeout expires.
-   *
-   * @param $item
-   * @return boolean
-   */
-  public function releaseItem($item);
-
-  /**
-   * Create a queue.
-   *
-   * Called during installation and should be used to perform any necessary
-   * initialization operations. This should not be confused with the
-   * constructor for these objects, which is called every time an object is
-   * instantiated to operate on a queue. This operation is only needed the
-   * first time a given queue is going to be initialized (for example, to make
-   * a new database table or directory to hold tasks for the queue -- it
-   * depends on the queue implementation if this is necessary at all).
-   */
-  public function createQueue();
-
-  /**
-   * Delete a queue and every item in the queue.
-   */
-  public function deleteQueue();
-}
-
-/**
- * Reliable queue interface.
- *
- * Classes implementing this interface preserve the order of messages and
- * guarantee that every item will be executed at least once.
- */
-interface DrupalReliableQueueInterface extends DrupalQueueInterface {
-}
-
-/**
- * Default queue implementation.
- */
-class SystemQueue implements DrupalReliableQueueInterface {
-  /**
-   * The name of the queue this instance is working with.
-   *
-   * @var string
-   */
-  protected $name;
-
-  public function __construct($name) {
-    $this->name = $name;
-  }
-
-  public function createItem($data) {
-    // During a Drupal 6.x to 8.x update, drupal_get_schema() does not contain
-    // the queue table yet, so we cannot rely on drupal_write_record().
-    $query = db_insert('queue')
-      ->fields(array(
-        'name' => $this->name,
-        'data' => serialize($data),
-        // We cannot rely on REQUEST_TIME because many items might be created
-        // by a single request which takes longer than 1 second.
-        'created' => time(),
-      ));
-    return (bool) $query->execute();
-  }
-
-  public function numberOfItems() {
-    return db_query('SELECT COUNT(item_id) FROM {queue} WHERE name = :name', array(':name' => $this->name))->fetchField();
-  }
-
-  public function claimItem($lease_time = 30) {
-    // Claim an item by updating its expire fields. If claim is not successful
-    // another thread may have claimed the item in the meantime. Therefore loop
-    // until an item is successfully claimed or we are reasonably sure there
-    // are no unclaimed items left.
-    while (TRUE) {
-      $item = db_query_range('SELECT data, item_id FROM {queue} q WHERE expire = 0 AND name = :name ORDER BY created ASC', 0, 1, array(':name' => $this->name))->fetchObject();
-      if ($item) {
-        // Try to update the item. Only one thread can succeed in UPDATEing the
-        // same row. We cannot rely on REQUEST_TIME because items might be
-        // claimed by a single consumer which runs longer than 1 second. If we
-        // continue to use REQUEST_TIME instead of the current time(), we steal
-        // time from the lease, and will tend to reset items before the lease
-        // should really expire.
-        $update = db_update('queue')
-          ->fields(array(
-            'expire' => time() + $lease_time,
-          ))
-          ->condition('item_id', $item->item_id)
-          ->condition('expire', 0);
-        // If there are affected rows, this update succeeded.
-        if ($update->execute()) {
-          $item->data = unserialize($item->data);
-          return $item;
-        }
-      }
-      else {
-        // No items currently available to claim.
-        return FALSE;
-      }
-    }
-  }
-
-  public function releaseItem($item) {
-    $update = db_update('queue')
-      ->fields(array(
-        'expire' => 0,
-      ))
-      ->condition('item_id', $item->item_id);
-      return $update->execute();
-  }
-
-  public function deleteItem($item) {
-    db_delete('queue')
-      ->condition('item_id', $item->item_id)
-      ->execute();
-  }
-
-  public function createQueue() {
-    // All tasks are stored in a single database table (which is created when
-    // Drupal is first installed) so there is nothing we need to do to create
-    // a new queue.
-  }
-
-  public function deleteQueue() {
-    db_delete('queue')
-      ->condition('name', $this->name)
-      ->execute();
-  }
-}
-
-/**
- * Static queue implementation.
- *
- * This allows "undelayed" variants of processes relying on the Queue
- * interface. The queue data resides in memory. It should only be used for
- * items that will be queued and dequeued within a given page request.
- */
-class MemoryQueue implements DrupalQueueInterface {
-  /**
-   * The queue data.
-   *
-   * @var array
-   */
-  protected $queue;
-
-  /**
-   * Counter for item ids.
-   *
-   * @var int
-   */
-  protected $id_sequence;
-
-  public function __construct($name) {
-    $this->queue = array();
-    $this->id_sequence = 0;
-  }
-
-  public function createItem($data) {
-    $item = new stdClass();
-    $item->item_id = $this->id_sequence++;
-    $item->data = $data;
-    $item->created = time();
-    $item->expire = 0;
-    $this->queue[$item->item_id] = $item;
-  }
-
-  public function numberOfItems() {
-    return count($this->queue);
-  }
-
-  public function claimItem($lease_time = 30) {
-    foreach ($this->queue as $key => $item) {
-      if ($item->expire == 0) {
-        $item->expire = time() + $lease_time;
-        $this->queue[$key] = $item;
-        return $item;
-      }
-    }
-    return FALSE;
-  }
-
-  public function deleteItem($item) {
-    unset($this->queue[$item->item_id]);
-  }
-
-  public function releaseItem($item) {
-    if (isset($this->queue[$item->item_id]) && $this->queue[$item->item_id]->expire != 0) {
-      $this->queue[$item->item_id]->expire = 0;
-      return TRUE;
-    }
-    return FALSE;
-  }
-
-  public function createQueue() {
-    // Nothing needed here.
-  }
-
-  public function deleteQueue() {
-    $this->queue = array();
-    $this->id_sequence = 0;
-  }
-}
-
-/**
- * @} End of "defgroup queue".
- */
diff --git a/core/modules/system/system.test b/core/modules/system/system.test
index 64774c4..ded5123 100644
--- a/core/modules/system/system.test
+++ b/core/modules/system/system.test
@@ -1811,98 +1811,6 @@ class SystemThemeFunctionalTest extends DrupalWebTestCase {
   }
 }
 
-
-/**
- * Test the basic queue functionality.
- */
-class QueueTestCase extends DrupalWebTestCase {
-  public static function getInfo() {
-    return array(
-      'name' => 'Queue functionality',
-      'description' => 'Queues and dequeues a set of items to check the basic queue functionality.',
-      'group' => 'System',
-    );
-  }
-
-  /**
-   * Queues and dequeues a set of items to check the basic queue functionality.
-   */
-  function testQueue() {
-    // Create two queues.
-    $queue1 = DrupalQueue::get($this->randomName());
-    $queue1->createQueue();
-    $queue2 = DrupalQueue::get($this->randomName());
-    $queue2->createQueue();
-
-    // Create four items.
-    $data = array();
-    for ($i = 0; $i < 4; $i++) {
-      $data[] = array($this->randomName() => $this->randomName());
-    }
-
-    // Queue items 1 and 2 in the queue1.
-    $queue1->createItem($data[0]);
-    $queue1->createItem($data[1]);
-
-    // Retrieve two items from queue1.
-    $items = array();
-    $new_items = array();
-
-    $items[] = $item = $queue1->claimItem();
-    $new_items[] = $item->data;
-
-    $items[] = $item = $queue1->claimItem();
-    $new_items[] = $item->data;
-
-    // First two dequeued items should match the first two items we queued.
-    $this->assertEqual($this->queueScore($data, $new_items), 2, t('Two items matched'));
-
-    // Add two more items.
-    $queue1->createItem($data[2]);
-    $queue1->createItem($data[3]);
-
-    $this->assertTrue($queue1->numberOfItems(), t('Queue 1 is not empty after adding items.'));
-    $this->assertFalse($queue2->numberOfItems(), t('Queue 2 is empty while Queue 1 has items'));
-
-    $items[] = $item = $queue1->claimItem();
-    $new_items[] = $item->data;
-
-    $items[] = $item = $queue1->claimItem();
-    $new_items[] = $item->data;
-
-    // All dequeued items should match the items we queued exactly once,
-    // therefore the score must be exactly 4.
-    $this->assertEqual($this->queueScore($data, $new_items), 4, t('Four items matched'));
-
-    // There should be no duplicate items.
-    $this->assertEqual($this->queueScore($new_items, $new_items), 4, t('Four items matched'));
-
-    // Delete all items from queue1.
-    foreach ($items as $item) {
-      $queue1->deleteItem($item);
-    }
-
-    // Check that both queues are empty.
-    $this->assertFalse($queue1->numberOfItems(), t('Queue 1 is empty'));
-    $this->assertFalse($queue2->numberOfItems(), t('Queue 2 is empty'));
-  }
-
-  /**
-   * This function returns the number of equal items in two arrays.
-   */
-  function queueScore($items, $new_items) {
-    $score = 0;
-    foreach ($items as $item) {
-      foreach ($new_items as $new_item) {
-        if ($item === $new_item) {
-          $score++;
-        }
-      }
-    }
-    return $score;
-  }
-}
-
 /**
  * Test token replacement in strings.
  */
diff --git a/core/modules/update/update.fetch.inc b/core/modules/update/update.fetch.inc
index 7ac0dbe..ec3bfbc 100644
--- a/core/modules/update/update.fetch.inc
+++ b/core/modules/update/update.fetch.inc
@@ -28,7 +28,7 @@ function update_manual_status() {
  * Process a step in the batch for fetching available update data.
  */
 function update_fetch_data_batch(&$context) {
-  $queue = DrupalQueue::get('update_fetch_tasks');
+  $queue = queue('update_fetch_tasks');
   if (empty($context['sandbox']['max'])) {
     $context['finished'] = 0;
     $context['sandbox']['max'] = $queue->numberOfItems();
@@ -99,7 +99,7 @@ function update_fetch_data_finished($success, $results) {
  * Attempt to drain the queue of tasks for release history data to fetch.
  */
 function _update_fetch_data() {
-  $queue = DrupalQueue::get('update_fetch_tasks');
+  $queue = queue('update_fetch_tasks');
   $end = time() + variable_get('update_max_fetch_time', UPDATE_MAX_FETCH_TIME);
   while (time() < $end && ($item = $queue->claimItem())) {
     _update_process_fetch_task($item->data);
@@ -235,7 +235,7 @@ function _update_create_fetch_task($project) {
   }
   $cid = 'fetch_task::' . $project['name'];
   if (empty($fetch_tasks[$cid])) {
-    $queue = DrupalQueue::get('update_fetch_tasks');
+    $queue = queue('update_fetch_tasks');
     $queue->createItem($project);
     db_insert('cache_update')
       ->fields(array(
diff --git a/core/modules/update/update.install b/core/modules/update/update.install
index f0d5499..9ff39d1 100644
--- a/core/modules/update/update.install
+++ b/core/modules/update/update.install
@@ -70,7 +70,7 @@ function update_schema() {
  * Implements hook_install().
  */
 function update_install() {
-  $queue = DrupalQueue::get('update_fetch_tasks', TRUE);
+  $queue = queue('update_fetch_tasks', TRUE);
   $queue->createQueue();
 }
 
@@ -91,7 +91,7 @@ function update_uninstall() {
   foreach ($variables as $variable) {
     variable_del($variable);
   }
-  $queue = DrupalQueue::get('update_fetch_tasks');
+  $queue = queue('update_fetch_tasks');
   $queue->deleteQueue();
 }