diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/AuthorFormatter.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/AuthorFormatter.php
new file mode 100644
index 0000000..5b5be15
--- /dev/null
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/AuthorFormatter.php
@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Field\Plugin\Field\FieldFormatter\AuthorFormatter.
+ */
+
+namespace Drupal\Core\Field\Plugin\Field\FieldFormatter;
+
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\FormatterBase;
+
+/**
+ * Plugin implementation of the 'author' formatter.
+ *
+ * @FieldFormatter(
+ *   id = "author",
+ *   label = @Translation("Author"),
+ *   description = @Translation("Display the referenced author user entity."),
+ *   field_types = {
+ *     "entity_reference"
+ *   }
+ * )
+ */
+class AuthorFormatter extends FormatterBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function viewElements(FieldItemListInterface $items) {
+    $elements = array();
+
+    foreach ($items as $delta => $item) {
+      /** @var $referenced_user \Drupal\user\UserInterface */
+      if ($referenced_user = $item->entity) {
+        $elements[$delta] = array(
+          '#theme' => 'username',
+          '#account' => $referenced_user,
+          '#link_options' => array('attributes' => array('rel' => 'author')),
+        );
+      }
+    }
+
+    return $elements;
+  }
+
+}
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/TimestampFormatter.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/TimestampFormatter.php
new file mode 100644
index 0000000..6861a00
--- /dev/null
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/TimestampFormatter.php
@@ -0,0 +1,40 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Field\Plugin\Field\FieldFormatter\TimestampFormatter.
+ */
+
+namespace Drupal\Core\Field\Plugin\Field\FieldFormatter;
+
+use Drupal\Core\Field\FormatterBase;
+use Drupal\Core\Field\FieldItemListInterface;
+
+/**
+ * Plugin implementation of the 'timestamp' formatter.
+ *
+ * @FieldFormatter(
+ *   id = "timestamp",
+ *   label = @Translation("Default"),
+ *   field_types = {
+ *     "timestamp",
+ *     "created",
+ *   }
+ * )
+ */
+class TimestampFormatter extends FormatterBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function viewElements(FieldItemListInterface $items) {
+    $elements = array();
+
+    foreach ($items as $delta => $item) {
+      $elements[$delta] = array('#markup' => format_date($item->value));
+    }
+
+    return $elements;
+  }
+
+}
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/BooleanItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/BooleanItem.php
index 14d0f83..f2951ac 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/BooleanItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/BooleanItem.php
@@ -18,7 +18,8 @@
  *   id = "boolean",
  *   label = @Translation("Boolean"),
  *   description = @Translation("An entity field containing a boolean value."),
- *   no_ui = TRUE
+ *   no_ui = TRUE,
+ *   default_widget = "boolean",
  * )
  */
 class BooleanItem extends FieldItemBase {
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/CreatedItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/CreatedItem.php
index 9b2e055..72c0ea9 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/CreatedItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/CreatedItem.php
@@ -14,7 +14,9 @@
  *   id = "created",
  *   label = @Translation("Created"),
  *   description = @Translation("An entity field containing a UNIX timestamp of when the entity has been created."),
- *   no_ui = TRUE
+ *   no_ui = TRUE,
+ *   default_widget = "timestamp",
+ *   default_formatter = "timestamp",
  * )
  */
 class CreatedItem extends TimestampItem {
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/TimestampItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/TimestampItem.php
index ba432e3..72f71a2 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/TimestampItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/TimestampItem.php
@@ -18,7 +18,9 @@
  *   id = "timestamp",
  *   label = @Translation("Timestamp"),
  *   description = @Translation("An entity field containing a UNIX timestamp value."),
- *   no_ui = TRUE
+ *   no_ui = TRUE,
+ *   default_widget = "timestamp",
+ *   default_formatter = "timestamp",
  * )
  */
 class TimestampItem extends FieldItemBase {
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/AuthorAutocompleteWidget.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/AuthorAutocompleteWidget.php
new file mode 100644
index 0000000..b126a93
--- /dev/null
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/AuthorAutocompleteWidget.php
@@ -0,0 +1,83 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Field\Plugin\Field\FieldWidget\RouteBasedAutocompleteWidget.
+ */
+
+namespace Drupal\Core\Field\Plugin\Field\FieldWidget;
+
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\WidgetBase;
+
+/**
+ * Plugin implementation of the 'route based autocomplete' widget.
+ *
+ * @FieldWidget(
+ *   id = "author_autocomplete",
+ *   label = @Translation("Author user reference autocomplete"),
+ *   field_types = {
+ *     "entity_reference",
+ *   }
+ * )
+ */
+class AuthorAutocompleteWidget extends RouteBasedAutocompleteWidget {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function defaultSettings() {
+    return array(
+      'route_name' => '',
+    ) + parent::defaultSettings();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, array &$form_state) {
+    $element = parent::formElement($items, $delta, $element, $form, $form_state);
+
+    $entity = $element['#entity'];
+    $element['target_id']['#default_value'] = $entity->getOwner()? $entity->getOwner()->getUsername() : '';
+
+    $user_config = \Drupal::config('user.settings');
+    $element['target_id']['#description'] = $this->t('Leave blank for %anonymous.', array('%anonymous' => $user_config->get('anonymous')));
+
+    $element['target_id']['#element_validate'] = array(array($this, 'elementValidate'));
+
+    return $element;
+  }
+
+  /**
+   * Validates an element.
+   *
+   * @todo Convert to massageFormValues() after https://drupal.org/node/2226723 lands.
+   */
+  public function elementValidate($element, &$form_state, $form) {
+    $form_builder = \Drupal::formBuilder();
+    $value = $element['#value'];
+    // The use of empty() is mandatory in the context of usernames
+    // as the empty string denotes the anonymous user. In case we
+    // are dealing with an anonymous user we set the user ID to 0.
+    if (empty($value)) {
+      $value = 0;
+    }
+    else {
+      $account = user_load_by_name($value);
+      if ($account !== FALSE) {
+        $value = $account->id();
+      }
+      else {
+        // Edge case: a non-existing numeric username should not be treated as
+        // a user ID (entity reference target_id). The ValidReference constraint
+        // would consider this a valid user ID, therefore we need additional
+        // validation here.
+        $form_builder->setError($element, $form_state, $this->t('The username %name does not exist.', array('%name' => $value)));
+        $value = NULL;
+      }
+    }
+    $form_builder->setValue($element, $value, $form_state);
+  }
+
+}
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/BooleanWidget.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/BooleanWidget.php
new file mode 100644
index 0000000..66f4d07
--- /dev/null
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/BooleanWidget.php
@@ -0,0 +1,38 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Field\Plugin\Field\FieldWidget\BooleanWidget.
+ */
+
+namespace Drupal\Core\Field\Plugin\Field\FieldWidget;
+
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\WidgetBase;
+
+/**
+ * Plugin implementation of the 'boolean' widget.
+ *
+ * @FieldWidget(
+ *   id = "boolean",
+ *   label = @Translation("Boolean"),
+ *   field_types = {
+ *     "boolean",
+ *   },
+ * )
+ */
+class BooleanWidget extends WidgetBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, array &$form_state) {
+    $element['value'] = $element + array(
+      '#type' => 'checkbox',
+      '#default_value' => isset($items[$delta]->value) ? $items[$delta]->value : NULL,
+    );
+
+    return $element;
+  }
+
+}
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/RouteBasedAutocompleteWidget.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/RouteBasedAutocompleteWidget.php
new file mode 100644
index 0000000..cf8b2c3
--- /dev/null
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/RouteBasedAutocompleteWidget.php
@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Field\Plugin\Field\FieldWidget\RouteBasedAutocompleteWidget.
+ */
+
+namespace Drupal\Core\Field\Plugin\Field\FieldWidget;
+
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\WidgetBase;
+
+/**
+ * Plugin implementation of the 'route based autocomplete' widget.
+ *
+ * @FieldWidget(
+ *   id = "route_based_autocomplete",
+ *   label = @Translation("Entity reference autocomplete (route-based)"),
+ *   field_types = {
+ *     "entity_reference",
+ *   }
+ * )
+ */
+class RouteBasedAutocompleteWidget extends WidgetBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function defaultSettings() {
+    return array(
+      'route_name' => '',
+    ) + parent::defaultSettings();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, array &$form_state) {
+    $element['target_id'] = $element + array(
+      '#type' => 'textfield',
+      '#default_value' => $items[$delta]->value,
+      '#autocomplete_route_name' => $this->getSetting('route_name'),
+    );
+
+    return $element;
+  }
+
+}
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/TimestampWidget.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/TimestampWidget.php
new file mode 100644
index 0000000..3cd1712
--- /dev/null
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/TimestampWidget.php
@@ -0,0 +1,81 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Field\Plugin\Field\FieldWidget\TimestampWidget.
+ */
+
+namespace Drupal\Core\Field\Plugin\Field\FieldWidget;
+
+use Drupal\Core\Datetime\DrupalDateTime;
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\WidgetBase;
+
+/**
+ * Plugin implementation of the 'timestamp' widget.
+ *
+ * @FieldWidget(
+ *   id = "timestamp",
+ *   label = @Translation("Timestamp"),
+ *   field_types = {
+ *     "timestamp",
+ *     "created",
+ *   }
+ * )
+ */
+class TimestampWidget extends WidgetBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function defaultSettings() {
+    return array(
+      'use_request_time_on_empty' => FALSE,
+    ) + parent::defaultSettings();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, array &$form_state) {
+    $default_value = isset($items[$delta]->value) ? format_date($items[$delta]->value, 'custom', 'Y-m-d H:i:s O') : '';
+    $element['value'] = $element + array(
+      '#type' => 'textfield',
+      '#default_value' => $default_value,
+      '#maxlength' => 25,
+      '#element_validate' => array(
+        array($this, 'elementValidate'),
+      ),
+    );
+
+    $timestamp = (int) $items[$delta]->value;
+    $created_timestamp = (int) $items->getEntity()->getCreatedTime();
+    $element['value']['#description'] = $this->t('Format: %time. The date format is YYYY-MM-DD and %timezone is the time zone offset from UTC. Leave blank to use the time of form submission.', array('%time' => !empty($default_value) ?
+        date_format(date_create($default_value), 'Y-m-d H:i:s O') : format_date($created_timestamp, 'custom', 'Y-m-d H:i:s O'), '%timezone' => !empty($default_value) ? date_format(date_create($default_value), 'O') : format_date($created_timestamp, 'custom', 'O')));
+
+    return $element;
+  }
+
+  /**
+   * Validates an element.
+   *
+   * @todo Convert to massageFormValues() after https://drupal.org/node/2226723 lands.
+   */
+  public function elementValidate($element, &$form_state, $form) {
+    $value = trim($element['#value']);
+    if (empty($value)) {
+      $value = $this->getSetting('use_request_time_on_empty') ? REQUEST_TIME : 0;
+    }
+    else {
+      $date = new DrupalDateTime($value);
+      if ($date->hasErrors()) {
+        $value = FALSE;
+      }
+      else {
+        $value = $date->getTimestamp();
+      }
+    }
+    form_set_value($element, $value, $form_state);
+  }
+
+}
diff --git a/core/modules/content_translation/lib/Drupal/content_translation/ContentTranslationHandler.php b/core/modules/content_translation/lib/Drupal/content_translation/ContentTranslationHandler.php
index 76723c2..f9dc87c 100644
--- a/core/modules/content_translation/lib/Drupal/content_translation/ContentTranslationHandler.php
+++ b/core/modules/content_translation/lib/Drupal/content_translation/ContentTranslationHandler.php
@@ -414,7 +414,7 @@ function entityFormValidate($form, &$form_state) {
       if (!empty($translation['name']) && !($account = user_load_by_name($translation['name']))) {
         form_set_error('content_translation][name', $form_state, t('The translation authoring username %name does not exist.', array('%name' => $translation['name'])));
       }
-      // Validate the "authored on" field.
+      // Validate the "created on" field.
       if (!empty($translation['created']) && strtotime($translation['created']) === FALSE) {
         form_set_error('content_translation][created', $form_state, t('You have to specify a valid translation authoring date.'));
       }
diff --git a/core/modules/datetime/datetime.module b/core/modules/datetime/datetime.module
index c8dd4d1..afc3588 100644
--- a/core/modules/datetime/datetime.module
+++ b/core/modules/datetime/datetime.module
@@ -984,23 +984,13 @@ function datetime_range_years($string, $date = NULL) {
 }
 
 /**
- * Implements hook_form_BASE_FORM_ID_alter() for node forms.
+ * Implements hook_entity_base_field_info_alter().
  */
-function datetime_form_node_form_alter(&$form, &$form_state, $form_id) {
-  $format_type = datetime_default_format_type();
-
-  // Alter the 'Authored on' date to use datetime.
-  $form['created']['#type'] = 'datetime';
-  $date_format = entity_load('date_format', 'html_date')->getPattern($format_type);
-  $time_format = entity_load('date_format', 'html_time')->getPattern($format_type);
-  $form['created']['#description'] = t('Format: %format. Leave blank to use the time of form submission.', array('%format' => datetime_format_example($date_format . ' ' . $time_format)));
-  unset($form['created']['#maxlength']);
-}
-
-/**
- * Implements hook_node_prepare_form().
- */
-function datetime_node_prepare_form(NodeInterface $node, $operation, array &$form_state) {
-  // Prepare the 'Authored on' date to use datetime.
-  $node->date = DrupalDateTime::createFromTimestamp($node->getCreatedTime());
+function datetime_entity_base_field_info_alter(&$fields, \Drupal\Core\Entity\EntityTypeInterface $entity_type) {
+  if ($entity_type->id() == 'node') {
+    $fields['created']->setDisplayOptions('form', array(
+      'type' => 'datetime_timestamp',
+      'weight' => 0,
+    ));
+  }
 }
diff --git a/core/modules/datetime/lib/Drupal/datetime/Plugin/Field/FieldWidget/DateTimeTimestampWidget.php b/core/modules/datetime/lib/Drupal/datetime/Plugin/Field/FieldWidget/DateTimeTimestampWidget.php
new file mode 100644
index 0000000..395dd81
--- /dev/null
+++ b/core/modules/datetime/lib/Drupal/datetime/Plugin/Field/FieldWidget/DateTimeTimestampWidget.php
@@ -0,0 +1,63 @@
+<?php
+/**
+ * @file
+ * Contains \Drupal\datetime\Plugin\Field\FieldWidget\DateTimeTimestampWidget.
+ */
+
+namespace Drupal\datetime\Plugin\Field\FieldWidget;
+
+use Drupal\Core\Datetime\DrupalDateTime;
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\WidgetBase;
+
+/**
+ * Plugin implementation of the 'datetime timestamp' widget.
+ *
+ * @FieldWidget(
+ *   id = "datetime_timestamp",
+ *   label = @Translation("Datetime Timestamp"),
+ *   field_types = {
+ *     "timestamp",
+ *     "created",
+ *   }
+ * )
+ */
+class DateTimeTimestampWidget extends WidgetBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, array &$form_state) {
+    $format_type = datetime_default_format_type();
+    $date_format = entity_load('date_format', 'html_date')->getPattern($format_type);
+    $time_format = entity_load('date_format', 'html_time')->getPattern($format_type);
+    $default_value = isset($items[$delta]->value) ? DrupalDateTime::createFromTimestamp($items[$delta]->value) : '';
+    $element['value'] = $element + array(
+      '#type' => 'datetime',
+      '#default_value' => $default_value,
+      '#element_validate' => array(
+        array($this, 'elementValidate'),
+      ),
+    );
+    $element['value']['#description'] = $this->t('Format: %format. Leave blank to use the time of form submission.', array('%format' => datetime_format_example($date_format . ' ' . $time_format)));
+
+    return $element;
+  }
+
+  /**
+   * Validates an element.
+   *
+   * @todo Convert to massageFormValues() after https://drupal.org/node/2226723 lands.
+   */
+  public function elementValidate($element, &$form_state, $form) {
+    $date = $element['#value']['object'];
+    if ($date->hasErrors()) {
+      $value = -1;
+    }
+    else {
+      $value = $date->getTimestamp();
+    }
+    form_set_value($element, $value, $form_state);
+  }
+
+}
diff --git a/core/modules/forum/config/install/rdf.mapping.node.forum.yml b/core/modules/forum/config/install/rdf.mapping.node.forum.yml
index 7db68c7..be874cd 100644
--- a/core/modules/forum/config/install/rdf.mapping.node.forum.yml
+++ b/core/modules/forum/config/install/rdf.mapping.node.forum.yml
@@ -11,12 +11,12 @@ fieldMappings:
     properties:
       - 'schema:dateCreated'
     datatype_callback:
-      callable: 'date_iso8601'
+      callable: 'Drupal\rdf\CommonDataConverter::dateIso8601Value'
   changed:
     properties:
       - 'schema:dateModified'
     datatype_callback:
-      callable: 'date_iso8601'
+      callable: 'Drupal\rdf\CommonDataConverter::dateIso8601Value'
   body:
     properties:
       - 'schema:text'
diff --git a/core/modules/forum/lib/Drupal/forum/Tests/ForumBlockTest.php b/core/modules/forum/lib/Drupal/forum/Tests/ForumBlockTest.php
index 1295c82..f7c7b05 100644
--- a/core/modules/forum/lib/Drupal/forum/Tests/ForumBlockTest.php
+++ b/core/modules/forum/lib/Drupal/forum/Tests/ForumBlockTest.php
@@ -175,8 +175,8 @@ protected function createForumTopics($count = 5) {
         'body[0][value]' => $body,
         // Forum posts are ordered by timestamp, so force a unique timestamp by
         // adding the index.
-        'created[date]' => $date->format('Y-m-d'),
-        'created[time]' => $date->format('H:i:s'),
+        'created[0][value][date]' => $date->format('Y-m-d'),
+        'created[0][value][time]' => $date->format('H:i:s'),
       );
 
       // Create the forum topic, preselecting the forum ID via a URL parameter.
diff --git a/core/modules/node/lib/Drupal/node/Entity/Node.php b/core/modules/node/lib/Drupal/node/Entity/Node.php
index 1fc6f03..0a77cff 100644
--- a/core/modules/node/lib/Drupal/node/Entity/Node.php
+++ b/core/modules/node/lib/Drupal/node/Entity/Node.php
@@ -369,13 +369,25 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
 
     $fields['uid'] = FieldDefinition::create('entity_reference')
       ->setLabel(t('Author'))
-      ->setDescription(t('The user that is the node author.'))
+      ->setDescription(t('The user ID of the node author.'))
       ->setRevisionable(TRUE)
+      ->setTranslatable(TRUE)
       ->setSettings(array(
         'target_type' => 'user',
         'default_value' => 0,
       ))
-      ->setTranslatable(TRUE);
+      ->setDisplayOptions('view', array(
+        'label' => 'hidden',
+        'type' => 'author',
+        'weight' => 0,
+      ))
+      ->setDisplayOptions('form', array(
+        'type' => 'author_autocomplete',
+        'weight' => -1,
+        'settings' => array(
+          'route_name' => 'user.autocomplete',
+        ),
+      ));
 
     $fields['status'] = FieldDefinition::create('boolean')
       ->setLabel(t('Publishing status'))
@@ -384,10 +396,23 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
       ->setTranslatable(TRUE);
 
     $fields['created'] = FieldDefinition::create('created')
-      ->setLabel(t('Created'))
+      ->setLabel(t('Publication date'))
       ->setDescription(t('The time that the node was created.'))
       ->setRevisionable(TRUE)
-      ->setTranslatable(TRUE);
+      ->setTranslatable(TRUE)
+      ->setDisplayOptions('view', array(
+        'label' => 'hidden',
+        'type' => 'timestamp',
+        'weight' => 0,
+      ))
+      ->setDisplayOptions('form', array(
+        'type' => 'timestamp',
+        'weight' => 0,
+        'settings' => array(
+          'use_request_time_on_empty' => TRUE,
+        ),
+      ))
+      ->setDisplayConfigurable('form', TRUE);
 
     $fields['changed'] = FieldDefinition::create('changed')
       ->setLabel(t('Changed'))
@@ -396,16 +421,22 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
       ->setTranslatable(TRUE);
 
     $fields['promote'] = FieldDefinition::create('boolean')
-      ->setLabel(t('Promote'))
-      ->setDescription(t('A boolean indicating whether the node should be displayed on the front page.'))
+      ->setLabel(t('Promoted to front page'))
       ->setRevisionable(TRUE)
-      ->setTranslatable(TRUE);
+      ->setTranslatable(TRUE)
+      ->setDisplayOptions('form', array(
+        'type' => 'boolean',
+        'weight' => -1,
+      ));
 
     $fields['sticky'] = FieldDefinition::create('boolean')
-      ->setLabel(t('Sticky'))
-      ->setDescription(t('A boolean indicating whether the node should be displayed at the top of lists in which it appears.'))
+      ->setLabel(t('Sticky at top of lists'))
       ->setRevisionable(TRUE)
-      ->setTranslatable(TRUE);
+      ->setTranslatable(TRUE)
+      ->setDisplayOptions('form', array(
+        'type' => 'boolean',
+        'weight' => 0,
+      ));
 
     $fields['revision_timestamp'] = FieldDefinition::create('timestamp')
       ->setLabel(t('Revision timestamp'))
@@ -420,11 +451,18 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
       ->setQueryable(FALSE)
       ->setRevisionable(TRUE);
 
-    $fields['log'] = FieldDefinition::create('string')
-      ->setLabel(t('Log'))
-      ->setDescription(t('The log entry explaining the changes in this revision.'))
+    $fields['log'] = FieldDefinition::create('string_long')
+      ->setLabel(t('Revision log message'))
+      ->setDescription(t('Briefly describe the changes you have made.'))
       ->setRevisionable(TRUE)
-      ->setTranslatable(TRUE);
+      ->setTranslatable(TRUE)
+      ->setDisplayOptions('form', array(
+        'type' => 'text_textarea',
+        'weight' => 0,
+        'settings' => array(
+          'rows' => 4,
+        ),
+      ));
 
     return $fields;
   }
diff --git a/core/modules/node/lib/Drupal/node/NodeForm.php b/core/modules/node/lib/Drupal/node/NodeForm.php
index 37bb7da..a5ba863 100644
--- a/core/modules/node/lib/Drupal/node/NodeForm.php
+++ b/core/modules/node/lib/Drupal/node/NodeForm.php
@@ -7,12 +7,10 @@
 
 namespace Drupal\node;
 
-use Drupal\Component\Utility\NestedArray;
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Datetime\DrupalDateTime;
 use Drupal\Core\Entity\ContentEntityForm;
 use Drupal\Core\Language\Language;
-use Drupal\Component\Utility\String;
 
 /**
  * Form controller for the node edit forms.
@@ -46,7 +44,6 @@ protected function prepareEntity() {
       }
     }
     else {
-      $node->date = format_date($node->getCreatedTime(), 'custom', 'Y-m-d H:i:s O');
       // Remove the log message from the original node entity.
       $node->log = NULL;
     }
@@ -59,6 +56,8 @@ public function form(array $form, array &$form_state) {
     /** @var \Drupal\node\NodeInterface $node */
     $node = $this->entity;
 
+    $form = parent::form($form, $form_state, $node);
+
     if ($this->operation == 'edit') {
       $form['#title'] = $this->t('<em>Edit @type</em> @title', array('@type' => node_get_type_label($node), '@title' => $node->label()));
     }
@@ -92,7 +91,8 @@ public function form(array $form, array &$form_state) {
       '#default_value' => $node->getUntranslated()->language()->id,
       '#languages' => Language::STATE_ALL,
       '#access' => isset($language_configuration['language_show']) && $language_configuration['language_show'],
-    );
+     );
+
 
     $form['advanced'] = array(
       '#type' => 'vertical_tabs',
@@ -124,14 +124,12 @@ public function form(array $form, array &$form_state) {
       '#default_value' => !empty($this->settings['options']['revision']),
       '#access' => $node->isNewRevision() || user_access('administer nodes'),
       '#group' => 'revision_information',
+      // Ensure the 'Create new revision' checkbox sits above the revision log
+      // message.
+      '#weight' => -1,
     );
 
-    $form['log'] = array(
-      '#type' => 'textarea',
-      '#title' => t('Revision log message'),
-      '#rows' => 4,
-      '#default_value' => !empty($node->log->value) ? $node->log->value : '',
-      '#description' => t('Briefly describe the changes you have made.'),
+    $form['log'] += array(
       '#states' => array(
         'visible' => array(
           ':input[name="revision"]' => array('checked' => TRUE),
@@ -162,26 +160,17 @@ public function form(array $form, array &$form_state) {
       '#optional' => TRUE,
     );
 
-    $form['uid'] = array(
-      '#type' => 'textfield',
-      '#title' => t('Authored by'),
-      '#maxlength' => 60,
-      '#autocomplete_route_name' => 'user.autocomplete',
-      '#default_value' => $node->getOwnerId()? $node->getOwner()->getUsername() : '',
-      '#weight' => -1,
-      '#description' => t('Leave blank for %anonymous.', array('%anonymous' => $user_config->get('anonymous'))),
+    $form['uid'] += array(
       '#group' => 'author',
       '#access' => user_access('administer nodes'),
     );
-    $form['created'] = array(
-      '#type' => 'textfield',
-      '#title' => t('Authored on'),
-      '#maxlength' => 25,
-      '#description' => t('Format: %time. The date format is YYYY-MM-DD and %timezone is the time zone offset from UTC. Leave blank to use the time of form submission.', array('%time' => !empty($node->date) ? date_format(date_create($node->date), 'Y-m-d H:i:s O') : format_date($node->getCreatedTime(), 'custom', 'Y-m-d H:i:s O'), '%timezone' => !empty($node->date) ? date_format(date_create($node->date), 'O') : format_date($node->getCreatedTime(), 'custom', 'O'))),
-      '#default_value' => !empty($node->date) ? $node->date : '',
+    $form['uid']['widget'][0]['value']['#title'] = $this->t('Authored by');
+
+    $form['created'] += array(
       '#group' => 'author',
       '#access' => user_access('administer nodes'),
     );
+    $form['created']['widget'][0]['value']['#title'] = $this->t('Authored on');
 
     // Node options for administrators.
     $form['options'] = array(
@@ -198,23 +187,17 @@ public function form(array $form, array &$form_state) {
       '#optional' => TRUE,
     );
 
-    $form['promote'] = array(
-      '#type' => 'checkbox',
-      '#title' => t('Promoted to front page'),
-      '#default_value' => $node->isPromoted(),
+    $form['promote'] += array(
       '#group' => 'options',
       '#access' => user_access('administer nodes'),
     );
 
-    $form['sticky'] = array(
-      '#type' => 'checkbox',
-      '#title' => t('Sticky at top of lists'),
-      '#default_value' => $node->isSticky(),
+    $form['sticky'] += array(
       '#group' => 'options',
       '#access' => user_access('administer nodes'),
     );
 
-    return parent::form($form, $form_state, $node);
+    return $form;
   }
 
   /**
@@ -308,21 +291,6 @@ public function validate(array $form, array &$form_state) {
       $this->setFormError('changed', $form_state, $this->t('The content on this page has either been modified by another user, or you have already submitted modifications using this form. As a result, your changes cannot be saved.'));
     }
 
-    // Validate the "authored by" field.
-    if (!empty($form_state['values']['uid']) && !($account = user_load_by_name($form_state['values']['uid']))) {
-      // The use of empty() is mandatory in the context of usernames
-      // as the empty string denotes the anonymous user. In case we
-      // are dealing with an anonymous user we set the user ID to 0.
-      $this->setFormError('uid', $form_state, $this->t('The username %name does not exist.', array('%name' => $form_state['values']['uid'])));
-    }
-
-    // Validate the "authored on" field.
-    // The date element contains the date object.
-    $date = $node->date instanceof DrupalDateTime ? $node->date : new DrupalDateTime($node->date);
-    if ($date->hasErrors()) {
-      $this->setFormError('date', $form_state, $this->t('You have to specify a valid date.'));
-    }
-
     // Invoke hook_node_validate() for validation needed by modules.
     // Can't use \Drupal::moduleHandler()->invokeAll(), because $form_state must
     // be receivable by reference.
@@ -417,14 +385,7 @@ public function unpublish(array $form, array &$form_state) {
   public function buildEntity(array $form, array &$form_state) {
     /** @var \Drupal\node\NodeInterface $entity */
     $entity = parent::buildEntity($form, $form_state);
-    // A user might assign the node author by entering a user name in the node
-    // form, which we then need to translate to a user ID.
-    if (!empty($form_state['values']['uid']) && $account = user_load_by_name($form_state['values']['uid'])) {
-      $entity->setOwnerId($account->id());
-    }
-    else {
-      $entity->setOwnerId(0);
-    }
+    $entity->setOwnerId($form_state['values']['uid'][0]['target_id']);
 
     if (!empty($form_state['values']['created']) && $form_state['values']['created'] instanceOf DrupalDateTime) {
       $entity->setCreatedTime($form_state['values']['created']->getTimestamp());
diff --git a/core/modules/node/lib/Drupal/node/NodeTranslationHandler.php b/core/modules/node/lib/Drupal/node/NodeTranslationHandler.php
index 21ab7e0..aea2d3b 100644
--- a/core/modules/node/lib/Drupal/node/NodeTranslationHandler.php
+++ b/core/modules/node/lib/Drupal/node/NodeTranslationHandler.php
@@ -80,8 +80,9 @@ public function entityFormEntityBuild($entity_type, EntityInterface $entity, arr
       $translation['status'] = $form_controller->getEntity()->isPublished();
       // $form['content_translation']['name'] is the equivalent field
       // for translation author uid.
-      $translation['name'] = $form_state['values']['uid'];
-      $translation['created'] = $form_state['values']['created'];
+      $account = user_load($form_state['values']['uid'][0]['target_id']);
+      $translation['name'] = $account ? $account->getUsername() : '';
+      $translation['created'] = format_date($form_state['values']['created'][0]['value'], 'custom', 'Y-m-d H:i:s O');
     }
     parent::entityFormEntityBuild($entity_type, $entity, $form, $form_state);
   }
diff --git a/core/modules/node/lib/Drupal/node/Tests/MultiStepNodeFormBasicOptionsTest.php b/core/modules/node/lib/Drupal/node/Tests/MultiStepNodeFormBasicOptionsTest.php
index 67bdbe3..5620a8f 100644
--- a/core/modules/node/lib/Drupal/node/Tests/MultiStepNodeFormBasicOptionsTest.php
+++ b/core/modules/node/lib/Drupal/node/Tests/MultiStepNodeFormBasicOptionsTest.php
@@ -62,13 +62,13 @@ function testMultiStepNodeFormBasicOptions() {
 
     $edit = array(
       'title[0][value]' => 'a',
-      'promote' => FALSE,
-      'sticky' => 1,
+      'promote[0][value]' => FALSE,
+      'sticky[0][value]' => 1,
       "{$this->field_name}[0][value]" => $this->randomString(32),
     );
     $this->drupalPostForm('node/add/page', $edit, t('Add another item'));
-    $this->assertNoFieldChecked('edit-promote', 'promote stayed unchecked');
-    $this->assertFieldChecked('edit-sticky', 'sticky stayed checked');
+    $this->assertNoFieldChecked('edit-promote-0-value', 'promote stayed unchecked');
+    $this->assertFieldChecked('edit-sticky-0-value', 'sticky stayed checked');
   }
 
 }
diff --git a/core/modules/node/lib/Drupal/node/Tests/NodeCacheTagsTest.php b/core/modules/node/lib/Drupal/node/Tests/NodeCacheTagsTest.php
index 962f2f8..f0c85c1 100644
--- a/core/modules/node/lib/Drupal/node/Tests/NodeCacheTagsTest.php
+++ b/core/modules/node/lib/Drupal/node/Tests/NodeCacheTagsTest.php
@@ -65,7 +65,7 @@ protected function createEntity() {
    * Each node must have an author.
    */
   protected function getAdditionalCacheTagsForEntity(EntityInterface $node) {
-    return array('user:' . $node->getOwnerId());
+    return array('user:' . $node->getOwnerId(), 'user_view:' . TRUE);
   }
 
 }
diff --git a/core/modules/node/lib/Drupal/node/Tests/NodeCreationTest.php b/core/modules/node/lib/Drupal/node/Tests/NodeCreationTest.php
index 540f952..1f39201 100644
--- a/core/modules/node/lib/Drupal/node/Tests/NodeCreationTest.php
+++ b/core/modules/node/lib/Drupal/node/Tests/NodeCreationTest.php
@@ -151,7 +151,7 @@ public function testAuthorAutocomplete() {
 
     $this->drupalGet('node/add/page');
 
-    $result = $this->xpath('//input[@id="edit-uid" and contains(@data-autocomplete-path, "user/autocomplete")]');
+    $result = $this->xpath('//input[@id="edit-uid-0-value" and contains(@data-autocomplete-path, "user/autocomplete")]');
     $this->assertEqual(count($result), 0, 'No autocompletion without access user profiles.');
 
     $admin_user = $this->drupalCreateUser(array('administer nodes', 'create page content', 'access user profiles'));
@@ -159,7 +159,7 @@ public function testAuthorAutocomplete() {
 
     $this->drupalGet('node/add/page');
 
-    $result = $this->xpath('//input[@id="edit-uid" and contains(@data-autocomplete-path, "user/autocomplete")]');
+    $result = $this->xpath('//input[@id="edit-uid-0-target-id" and contains(@data-autocomplete-path, "user/autocomplete")]');
     $this->assertEqual(count($result), 1, 'Ensure that the user does have access to the autocompletion');
   }
 
diff --git a/core/modules/node/lib/Drupal/node/Tests/NodeTranslationUITest.php b/core/modules/node/lib/Drupal/node/Tests/NodeTranslationUITest.php
index 95eba8c..35b2a9d 100644
--- a/core/modules/node/lib/Drupal/node/Tests/NodeTranslationUITest.php
+++ b/core/modules/node/lib/Drupal/node/Tests/NodeTranslationUITest.php
@@ -158,11 +158,11 @@ protected function doTestAuthoringInfo() {
         'promote' => (bool) mt_rand(0, 1),
       );
       $edit = array(
-        'uid' => $user->getUsername(),
-        'created[date]' => format_date($values[$langcode]['created'], 'custom', 'Y-m-d'),
-        'created[time]' => format_date($values[$langcode]['created'], 'custom', 'H:i:s'),
-        'sticky' => $values[$langcode]['sticky'],
-        'promote' => $values[$langcode]['promote'],
+        'uid[0][target_id]' => $user->getUsername(),
+        'created[0][value][date]' => format_date($values[$langcode]['created'], 'custom', 'Y-m-d'),
+        'created[0][value][time]' => format_date($values[$langcode]['created'], 'custom', 'H:i:s'),
+        'sticky[0][value]' => $values[$langcode]['sticky'],
+        'promote[0][value]' => $values[$langcode]['promote'],
       );
       $this->drupalPostForm($path, $edit, $this->getFormSubmitAction($entity, $langcode), array('language' => $languages[$langcode]));
     }
diff --git a/core/modules/node/lib/Drupal/node/Tests/PageEditTest.php b/core/modules/node/lib/Drupal/node/Tests/PageEditTest.php
index 2361d13..ff97e9a 100644
--- a/core/modules/node/lib/Drupal/node/Tests/PageEditTest.php
+++ b/core/modules/node/lib/Drupal/node/Tests/PageEditTest.php
@@ -114,21 +114,21 @@ function testPageAuthoredBy() {
 
     // Try to change the 'authored by' field to an invalid user name.
     $edit = array(
-      'uid' => 'invalid-name',
+      'uid[0][target_id]' => 'invalid-name',
     );
     $this->drupalPostForm('node/' . $node->id() . '/edit', $edit, t('Save and keep published'));
-    $this->assertText('The username invalid-name does not exist.');
+    $this->assertRaw(format_string('The username %name does not exist.', array('%name' => 'invalid-name')));
 
     // Change the authored by field to an empty string, which should assign
     // authorship to the anonymous user (uid 0).
-    $edit['uid'] = '';
+    $edit['uid[0][target_id]'] = '';
     $this->drupalPostForm('node/' . $node->id() . '/edit', $edit, t('Save and keep published'));
     $node = node_load($node->id(), TRUE);
     $this->assertIdentical($node->getOwnerId(), '0', 'Node authored by anonymous user.');
 
     // Change the authored by field to another user's name (that is not
     // logged in).
-    $edit['uid'] = $this->web_user->getUsername();
+    $edit['uid[0][target_id]'] = $this->web_user->getUsername();
     $this->drupalPostForm('node/' . $node->id() . '/edit', $edit, t('Save and keep published'));
     $node = node_load($node->id(), TRUE);
     $this->assertIdentical($node->getOwnerId(), $this->web_user->id(), 'Node authored by normal user.');
@@ -136,6 +136,6 @@ function testPageAuthoredBy() {
     // Check that normal users cannot change the authored by information.
     $this->drupalLogin($this->web_user);
     $this->drupalGet('node/' . $node->id() . '/edit');
-    $this->assertNoFieldByName('uid');
+    $this->assertNoFieldByName('uid[0][target_id]');
   }
 }
diff --git a/core/modules/node/lib/Drupal/node/Tests/PagePreviewTest.php b/core/modules/node/lib/Drupal/node/Tests/PagePreviewTest.php
index 48a8ea6..4a6cebe 100644
--- a/core/modules/node/lib/Drupal/node/Tests/PagePreviewTest.php
+++ b/core/modules/node/lib/Drupal/node/Tests/PagePreviewTest.php
@@ -192,7 +192,7 @@ function testPagePreviewWithRevisions() {
     $edit[$title_key] = $this->randomName(8);
     $edit[$body_key] = $this->randomName(16);
     $edit[$term_key] = $this->term->id();
-    $edit['log'] = $this->randomName(32);
+    $edit['log[0][value]'] = $this->randomName(32);
     $this->drupalPostForm('node/add/page', $edit, t('Preview'));
 
     // Check that the preview is displaying the title, body and term.
@@ -207,7 +207,7 @@ function testPagePreviewWithRevisions() {
     $this->assertFieldByName($term_key, $edit[$term_key], 'Term field displayed.');
 
     // Check that the log field has the correct value.
-    $this->assertFieldByName('log', $edit['log'], 'Log field displayed.');
+    $this->assertFieldByName('log[0][value]', $edit['log[0][value]'], 'Log field displayed.');
   }
 
 }
diff --git a/core/modules/node/node.module b/core/modules/node/node.module
index e749f86..1e15a1d 100644
--- a/core/modules/node/node.module
+++ b/core/modules/node/node.module
@@ -179,6 +179,12 @@ function node_theme() {
       'base hook' => 'field',
       'template' => 'field--node--title',
     ),
+    'field__node__uid' => array(
+      'base hook' => 'field',
+    ),
+    'field__node__created' => array(
+      'base hook' => 'field',
+    ),
   );
 }
 
@@ -213,20 +219,6 @@ function node_entity_view_display_alter(EntityViewDisplayInterface $display, $co
 }
 
 /**
- * Implements hook_entity_form_display_alter().
- */
-function node_entity_form_display_alter(EntityFormDisplayInterface $form_display, $context) {
-  if ($context['entity_type'] == 'node') {
-    $node_type = node_type_load($context['bundle']);
-    // @todo Reconsider when per-bundle overrides of field definitions are
-    //   possible - https://drupal.org/node/2114707.
-    if (!$node_type->has_title) {
-      $form_display->removeComponent('title');
-    }
-  }
-}
-
-/**
  * Entity URI callback.
  *
  * @param \Drupal\node\NodeInterface $node
@@ -640,14 +632,9 @@ function template_preprocess_node(&$variables) {
   $variables['node'] = $variables['elements']['#node'];
   /** @var \Drupal\node\NodeInterface $node */
   $node = $variables['node'];
-
-  $variables['date'] = format_date($node->getCreatedTime());
-  $username = array(
-    '#theme' => 'username',
-    '#account' => $node->getOwner(),
-    '#link_options' => array('attributes' => array('rel' => 'author')),
-  );
-  $variables['name'] = drupal_render($username);
+  $variables['date'] = drupal_render($variables['elements']['created'], TRUE);
+  unset($variables['elements']['created']);
+  $variables['name'] = drupal_render($variables['elements']['uid'], TRUE);
 
   $variables['node_url'] = $node->url('canonical', array(
     'language' => $node->language(),
@@ -709,6 +696,57 @@ function template_preprocess_node(&$variables) {
 }
 
 /**
+ * Returns HTML for the node 'title' field.
+ *
+ * This is an override of theme_field() for the node 'title' field. See that
+ * function for documentation about its details and overrides.
+ *
+ * @param array $variables
+ *   An associative array. See theme_field() for details.
+ *
+ * @see theme_field()
+ *
+ * @ingroup themeable
+ */
+function theme_field__node__title($variables) {
+  return '<span' . new Attribute($variables['attributes']) . '>' . drupal_render($variables['items']) . '</span>';
+}
+
+/**
+ * Returns HTML for the node 'uid' field.
+ *
+ * This is an override of theme_field() for the node 'uid' field. See that
+ * function for documentation about its details and overrides.
+ *
+ * @param array $variables
+ *   An associative array. See theme_field() for details.
+ *
+ * @see theme_field()
+ *
+ * @ingroup themeable
+ */
+function theme_field__node__uid($variables) {
+  return '<span' . new Attribute($variables['attributes']) . '>' . drupal_render($variables['items']) . '</span>';
+}
+
+/**
+ * Returns HTML for the node 'created' field.
+ *
+ * This is an override of theme_field() for the node 'created' field. See that
+ * function for documentation about its details and overrides.
+ *
+ * @param array $variables
+ *   An associative array. See theme_field() for details.
+ *
+ * @see theme_field()
+ *
+ * @ingroup themeable
+ */
+function theme_field__node__created($variables) {
+  return '<span' . new Attribute($variables['attributes']) . '>' . drupal_render($variables['items']) . '</span>';
+}
+
+/**
  * Implements hook_permission().
  */
 function node_permission() {
diff --git a/core/modules/node/templates/node.html.twig b/core/modules/node/templates/node.html.twig
index ae1162e..602e676 100644
--- a/core/modules/node/templates/node.html.twig
+++ b/core/modules/node/templates/node.html.twig
@@ -21,10 +21,8 @@
  *   {{ content|without('field_example') %} to temporarily suppress the printing
  *   of a given child element.
  * - user_picture: The node author's picture from user-picture.html.twig.
- * - date: Formatted creation date. Preprocess functions can reformat it by
- *   calling format_date() with the desired parameters on
- *   $variables['created'].
- * - name: Themed username of node author output from theme_username().
+ * - date: Themed creation date field.
+ * - name: Themed author date field.
  * - node_url: Direct URL of the current node.
  * - display_submitted: Whether submission information should be displayed.
  * - submitted: Submission information created from name and date during
diff --git a/core/modules/rdf/lib/Drupal/rdf/CommonDataConverter.php b/core/modules/rdf/lib/Drupal/rdf/CommonDataConverter.php
index e27f48b..c91f947 100644
--- a/core/modules/rdf/lib/Drupal/rdf/CommonDataConverter.php
+++ b/core/modules/rdf/lib/Drupal/rdf/CommonDataConverter.php
@@ -23,4 +23,18 @@ class CommonDataConverter {
   static function rawValue($data) {
     return $data;
   }
+
+  /**
+   * Converts a date entity field array into an ISO 8601 timestamp string.
+   *
+   * @param array $data
+   *   The array containing the 'value' element.
+   *
+   * @return string
+   *   Returns the ISO 8601 timestamp.
+   */
+  static function dateIso8601Value($data) {
+    return date_iso8601($data['value']);
+  }
+
 }
diff --git a/core/modules/rdf/lib/Drupal/rdf/Tests/CommentAttributesTest.php b/core/modules/rdf/lib/Drupal/rdf/Tests/CommentAttributesTest.php
index f152e0b..99d5018 100644
--- a/core/modules/rdf/lib/Drupal/rdf/Tests/CommentAttributesTest.php
+++ b/core/modules/rdf/lib/Drupal/rdf/Tests/CommentAttributesTest.php
@@ -77,12 +77,12 @@ public function setUp() {
       'created' => array(
         'properties' => array('dc:date', 'dc:created'),
         'datatype' => 'xsd:dateTime',
-        'datatype_callback' => array('callable' => 'date_iso8601'),
+        'datatype_callback' => array('callable' => 'Drupal\rdf\CommonDataConverter::dateIso8601Value'),
       ),
       'changed' => array(
         'properties' => array('dc:modified'),
         'datatype' => 'xsd:dateTime',
-        'datatype_callback' => array('callable' => 'date_iso8601'),
+        'datatype_callback' => array('callable' => 'Drupal\rdf\CommonDataConverter::dateIso8601Value'),
       ),
       'comment_body' => array(
         'properties' => array('content:encoded'),
diff --git a/core/modules/rdf/lib/Drupal/rdf/Tests/CrudTest.php b/core/modules/rdf/lib/Drupal/rdf/Tests/CrudTest.php
index 26f793d..fd0d0a1 100644
--- a/core/modules/rdf/lib/Drupal/rdf/Tests/CrudTest.php
+++ b/core/modules/rdf/lib/Drupal/rdf/Tests/CrudTest.php
@@ -81,7 +81,7 @@ function testFieldMapping() {
     $mapping = array(
       'properties' => array('dc:created'),
       'datatype' => 'xsd:dateTime',
-      'datatype_callback' => array('callable' => 'date_iso8601'),
+      'datatype_callback' => array('callable' => 'Drupal\rdf\CommonDataConverter::dateIso8601Value'),
     );
     rdf_get_mapping($this->entity_type, $this->bundle)
       ->setFieldMapping($field_name, $mapping)
@@ -94,7 +94,7 @@ function testFieldMapping() {
     $mapping = array(
       'properties' => array('dc:date'),
       'datatype' => 'foo:bar',
-      'datatype_callback' => array('callable' => 'date_iso8601'),
+      'datatype_callback' => array('callable' => 'Drupal\rdf\CommonDataConverter::dateIso8601Value'),
     );
     rdf_get_mapping($this->entity_type, $this->bundle)
       ->setFieldMapping($field_name, $mapping)
diff --git a/core/modules/rdf/lib/Drupal/rdf/Tests/NodeAttributesTest.php b/core/modules/rdf/lib/Drupal/rdf/Tests/NodeAttributesTest.php
index 76e1af6..ff29448 100644
--- a/core/modules/rdf/lib/Drupal/rdf/Tests/NodeAttributesTest.php
+++ b/core/modules/rdf/lib/Drupal/rdf/Tests/NodeAttributesTest.php
@@ -42,7 +42,7 @@ public function setUp() {
       ->setFieldMapping('created', array(
         'properties' => array('dc:date', 'dc:created'),
         'datatype' => 'xsd:dateTime',
-        'datatype_callback' => array('callable' => 'date_iso8601'),
+        'datatype_callback' => array('callable' => 'Drupal\rdf\CommonDataConverter::dateIso8601Value'),
       ))
       ->save();
   }
diff --git a/core/modules/rdf/lib/Drupal/rdf/Tests/TrackerAttributesTest.php b/core/modules/rdf/lib/Drupal/rdf/Tests/TrackerAttributesTest.php
index fa7f673..0279c4b 100644
--- a/core/modules/rdf/lib/Drupal/rdf/Tests/TrackerAttributesTest.php
+++ b/core/modules/rdf/lib/Drupal/rdf/Tests/TrackerAttributesTest.php
@@ -47,12 +47,12 @@ function setUp() {
       'created' => array(
         'properties' => array('dc:date', 'dc:created'),
         'datatype' => 'xsd:dateTime',
-        'datatype_callback' => array('callable' => 'date_iso8601'),
+        'datatype_callback' => array('callable' => 'Drupal\rdf\CommonDataConverter::dateIso8601Value'),
       ),
       'changed' => array(
         'properties' => array('dc:modified'),
         'datatype' => 'xsd:dateTime',
-        'datatype_callback' => array('callable' => 'date_iso8601'),
+        'datatype_callback' => array('callable' => 'Drupal\rdf\CommonDataConverter::dateIso8601Value'),
       ),
       'body' => array(
         'properties' => array('content:encoded'),
diff --git a/core/modules/rdf/rdf.module b/core/modules/rdf/rdf.module
index 8ea735b..b1f2043 100644
--- a/core/modules/rdf/rdf.module
+++ b/core/modules/rdf/rdf.module
@@ -233,7 +233,7 @@ function rdf_comment_load($comments) {
     // to optimize performance for websites that implement an entity cache.
     $created_mapping = rdf_get_mapping('comment', $comment->bundle())
       ->getPreparedFieldMapping('created');
-    $comment->rdf_data['date'] = rdf_rdfa_attributes($created_mapping, $comment->getCreatedTime());
+    $comment->rdf_data['date'] = rdf_rdfa_attributes($created_mapping, $comment->get('created')[0]->getValue());
     $entity = $comment->getCommentedEntity();
     $comment->rdf_data['entity_uri'] = $entity->url();
     if ($comment->hasParentComment()) {
@@ -305,7 +305,7 @@ function rdf_preprocess_node(&$variables) {
   // Adds RDFa markup for the date.
   $created_mapping = $mapping->getPreparedFieldMapping('created');
   if (!empty($created_mapping) && $variables['submitted']) {
-    $date_attributes = rdf_rdfa_attributes($created_mapping, $variables['node']->getCreatedTime());
+    $date_attributes = rdf_rdfa_attributes($created_mapping, $variables['node']->get('created')[0]->getValue());
     $rdf_metadata = array(
       '#theme' => 'rdf_metadata',
       '#metadata' => array($date_attributes),
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/LegacyTest.php b/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/LegacyTest.php
index cddfefd..b45c929 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/LegacyTest.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/LegacyTest.php
@@ -38,8 +38,8 @@ function testTaxonomyLegacyNode() {
     $date = new DrupalDateTime('1969-01-01 00:00:00');
     $edit = array();
     $edit['title[0][value]'] = $this->randomName();
-    $edit['created[date]'] = $date->format('Y-m-d');
-    $edit['created[time]'] = $date->format('H:i:s');
+    $edit['created[0][value][date]'] = $date->format('Y-m-d');
+    $edit['created[0][value][time]'] = $date->format('H:i:s');
     $edit['body[0][value]'] = $this->randomName();
     $edit['field_tags'] = $this->randomName();
     $this->drupalPostForm('node/add/article', $edit, t('Save and publish'));
diff --git a/core/modules/text/lib/Drupal/text/Plugin/Field/FieldWidget/TextareaWidget.php b/core/modules/text/lib/Drupal/text/Plugin/Field/FieldWidget/TextareaWidget.php
index 3c57008..1b41a93 100644
--- a/core/modules/text/lib/Drupal/text/Plugin/Field/FieldWidget/TextareaWidget.php
+++ b/core/modules/text/lib/Drupal/text/Plugin/Field/FieldWidget/TextareaWidget.php
@@ -18,7 +18,8 @@
  *   id = "text_textarea",
  *   label = @Translation("Text area (multiple rows)"),
  *   field_types = {
- *     "text_long"
+ *     "text_long",
+ *     "string_long",
  *   }
  * )
  */
diff --git a/core/modules/tracker/tracker.pages.inc b/core/modules/tracker/tracker.pages.inc
index 85fa119..87c8f28 100644
--- a/core/modules/tracker/tracker.pages.inc
+++ b/core/modules/tracker/tracker.pages.inc
@@ -121,7 +121,7 @@ function tracker_page($account = NULL) {
         $last_activity_attributes = rdf_rdfa_attributes($last_activity_mapping, $node->last_activity);
         if ($node->comment_count == 0) {
           $changed_mapping = $mapping->getPreparedFieldMapping('changed');
-          $changed_attributes = rdf_rdfa_attributes($changed_mapping, $node->last_activity);
+          $changed_attributes = rdf_rdfa_attributes($changed_mapping, array('value' => $node->last_activity));
           $last_activity_attributes['property'] = array_merge($last_activity_attributes['property'], $changed_attributes['property']);
         }
         $row['last updated'] += $last_activity_attributes;
diff --git a/core/profiles/standard/config/install/rdf.mapping.comment.node__comment.yml b/core/profiles/standard/config/install/rdf.mapping.comment.node__comment.yml
index 70f25b1..f4811c6 100644
--- a/core/profiles/standard/config/install/rdf.mapping.comment.node__comment.yml
+++ b/core/profiles/standard/config/install/rdf.mapping.comment.node__comment.yml
@@ -11,12 +11,12 @@ fieldMappings:
     properties:
       - 'schema:dateCreated'
     datatype_callback:
-      callable: 'date_iso8601'
+      callable: 'Drupal\rdf\CommonDataConverter::dateIso8601Value'
   changed:
     properties:
       - 'schema:dateModified'
     datatype_callback:
-      callable: 'date_iso8601'
+      callable: 'Drupal\rdf\CommonDataConverter::dateIso8601Value'
   comment_body:
     properties:
       - 'schema:text'
diff --git a/core/profiles/standard/config/install/rdf.mapping.node.article.yml b/core/profiles/standard/config/install/rdf.mapping.node.article.yml
index 10147e7..d1b7f80 100644
--- a/core/profiles/standard/config/install/rdf.mapping.node.article.yml
+++ b/core/profiles/standard/config/install/rdf.mapping.node.article.yml
@@ -11,12 +11,12 @@ fieldMappings:
     properties:
       - 'schema:dateCreated'
     datatype_callback:
-      callable: 'date_iso8601'
+      callable: 'Drupal\rdf\CommonDataConverter::dateIso8601Value'
   changed:
     properties:
       - 'schema:dateModified'
     datatype_callback:
-      callable: 'date_iso8601'
+      callable: 'Drupal\rdf\CommonDataConverter::dateIso8601Value'
   body:
     properties:
       - 'schema:text'
diff --git a/core/profiles/standard/config/install/rdf.mapping.node.page.yml b/core/profiles/standard/config/install/rdf.mapping.node.page.yml
index 8a5d377..38120ff 100644
--- a/core/profiles/standard/config/install/rdf.mapping.node.page.yml
+++ b/core/profiles/standard/config/install/rdf.mapping.node.page.yml
@@ -11,12 +11,12 @@ fieldMappings:
     properties:
       - 'schema:dateCreated'
     datatype_callback:
-      callable: 'date_iso8601'
+      callable: 'Drupal\rdf\CommonDataConverter::dateIso8601Value'
   changed:
     properties:
       - 'schema:dateModified'
     datatype_callback:
-      callable: 'date_iso8601'
+      callable: 'Drupal\rdf\CommonDataConverter::dateIso8601Value'
   body:
     properties:
       - 'schema:text'
diff --git a/core/themes/bartik/templates/node.html.twig b/core/themes/bartik/templates/node.html.twig
index 2848899..107df54 100644
--- a/core/themes/bartik/templates/node.html.twig
+++ b/core/themes/bartik/templates/node.html.twig
@@ -21,10 +21,8 @@
  *   {{ content|without('field_example') }} to exclude the printing of a
  *   given child element.
  * - user_picture: The node author's picture from user-picture.html.twig.
- * - date: Formatted creation date. Preprocess functions can reformat it by
- *   calling format_date() with the desired parameters on
- *   $variables['created'].
- * - name: Themed username of node author output from theme_username().
+ * - date: Themed creation date field.
+ * - name: Themed author date field.
  * - node_url: Direct URL of the current node.
  * - display_submitted: Whether submission information should be displayed.
  * - submitted: Submission information created from name and date during