diff --git a/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
index 41db80601fabc13c4695037e2514d38333d53c62..55a3875588e4378e03f850625f7e5727c050a4a0 100644
--- a/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -1,6 +1,7 @@
 <?php
 
 use Drupal\Component\Utility\NestedArray;
+use Drupal\Core\DrupalKernel;
 use Drupal\Core\Database\Database;
 use Drupal\Core\DependencyInjection\ContainerBuilder;
 use Symfony\Component\ClassLoader\UniversalClassLoader;
@@ -128,39 +129,44 @@
 const DRUPAL_BOOTSTRAP_CONFIGURATION = 0;
 
 /**
- * Second bootstrap phase: try to serve a cached page.
+ * Second bootstrap phase, initalize a kernel.
  */
-const DRUPAL_BOOTSTRAP_PAGE_CACHE = 1;
+const DRUPAL_BOOTSTRAP_KERNEL = 1;
 
 /**
- * Third bootstrap phase: initialize database layer.
+ * Third bootstrap phase: try to serve a cached page.
  */
-const DRUPAL_BOOTSTRAP_DATABASE = 2;
+const DRUPAL_BOOTSTRAP_PAGE_CACHE = 2;
 
 /**
- * Fourth bootstrap phase: initialize the variable system.
+ * Fourth bootstrap phase: initialize database layer.
  */
-const DRUPAL_BOOTSTRAP_VARIABLES = 3;
+const DRUPAL_BOOTSTRAP_DATABASE = 3;
 
 /**
- * Fifth bootstrap phase: initialize session handling.
+ * Fifth bootstrap phase: initialize the variable system.
  */
-const DRUPAL_BOOTSTRAP_SESSION = 4;
+const DRUPAL_BOOTSTRAP_VARIABLES = 4;
 
 /**
- * Sixth bootstrap phase: set up the page header.
+ * Sixth bootstrap phase: initialize session handling.
  */
-const DRUPAL_BOOTSTRAP_PAGE_HEADER = 5;
+const DRUPAL_BOOTSTRAP_SESSION = 5;
 
 /**
- * Seventh bootstrap phase: load code for subsystems and modules.
+ * Seventh bootstrap phase: set up the page header.
  */
-const DRUPAL_BOOTSTRAP_CODE = 6;
+const DRUPAL_BOOTSTRAP_PAGE_HEADER = 6;
+
+/**
+ * Eighth bootstrap phase: load code for subsystems and modules.
+ */
+const DRUPAL_BOOTSTRAP_CODE = 7;
 
 /**
  * Final bootstrap phase: initialize language, path, theme, and modules.
  */
-const DRUPAL_BOOTSTRAP_FULL = 7;
+const DRUPAL_BOOTSTRAP_FULL = 8;
 
 /**
  * Role ID for anonymous users; should match what's in the "role" table.
@@ -2105,6 +2111,7 @@ function drupal_bootstrap($phase = NULL, $new_phase = TRUE) {
   // Not drupal_static(), because does not depend on any run-time information.
   static $phases = array(
     DRUPAL_BOOTSTRAP_CONFIGURATION,
+    DRUPAL_BOOTSTRAP_KERNEL,
     DRUPAL_BOOTSTRAP_PAGE_CACHE,
     DRUPAL_BOOTSTRAP_DATABASE,
     DRUPAL_BOOTSTRAP_VARIABLES,
@@ -2115,14 +2122,15 @@ function drupal_bootstrap($phase = NULL, $new_phase = TRUE) {
   );
   // Not drupal_static(), because the only legitimate API to control this is to
   // call drupal_bootstrap() with a new phase parameter.
-  static $final_phase;
+  static $final_phase = -1;
   // Not drupal_static(), because it's impossible to roll back to an earlier
   // bootstrap state.
   static $stored_phase = -1;
 
-  // When not recursing, store the phase name so it's not forgotten while
-  // recursing.
-  if ($new_phase) {
+  // When not recursing, store the phase name so it's not forgotten during
+  // recursion. Additionally, ensure that $final_phase is never rolled back to an
+  // earlier bootstrap state.
+  if ($new_phase && $phase > $final_phase) {
     $final_phase = $phase;
   }
   if (isset($phase)) {
@@ -2142,6 +2150,10 @@ function drupal_bootstrap($phase = NULL, $new_phase = TRUE) {
           _drupal_bootstrap_configuration();
           break;
 
+        case DRUPAL_BOOTSTRAP_KERNEL:
+          _drupal_bootstrap_kernel();
+          break;
+
         case DRUPAL_BOOTSTRAP_PAGE_CACHE:
           _drupal_bootstrap_page_cache();
           break;
@@ -2274,6 +2286,18 @@ function _drupal_bootstrap_configuration() {
   }
 }
 
+/**
+ * Initialize the kernel / service container.
+ */
+function _drupal_bootstrap_kernel() {
+  // Normally, index.php puts a container in drupal_container() by creating a
+  // kernel. If there is no container yet, create one.
+  if (!drupal_container()) {
+    $kernel = new DrupalKernel('prod', FALSE, drupal_classloader());
+    $kernel->boot();
+  }
+}
+
 /**
  * Attempts to serve a page from the cache.
  */
@@ -2410,91 +2434,28 @@ function drupal_get_bootstrap_phase() {
 /**
  * Retrieves the Drupal Container to standardize object construction.
  *
- * On a normal page request the container is built by the kernel and passed in
- * to this function which stores it statically. Any full bootstrap outside of
- * the context of a page request will require a container with a minimal set of
- * services. If this function is called without the $rebuild parameter, and no
- * container object has been statically cached, it builds this minimal container,
- * registering the services that are required.
+ * The container is built by the kernel and passed in to this function which
+ * stores it statically. The container always contains the services from
+ * \Drupal\Core\CoreBundle, the bundles of enabled modules and any other
+ * bundles defined in $GLOBALS['conf']['container_bundles'].
  *
  * @see Drupal\Core\DrupalKernel
  *
  * @param Symfony\Component\DependencyInjection\Container $new_container
- *   A new container instance to replace the current.
- * @param bool $rebuild
- *   (optional) Internal use only. Whether to enforce a rebuild of the container.
- *   Used by the testing framework to inject a fresh container for unit tests.
+ *   (optional) A new container instance to replace the current.
  *
- * @return Symfony\Component\DependencyInjection\Container
+ * @return Symfony\Component\DependencyInjection\Container|bool
  *   The instance of the Container used to set up and maintain object
- *   instances.
+ *   instances or FALSE if none exist yet.
  */
-function drupal_container(Container $new_container = NULL, $rebuild = FALSE) {
+function drupal_container(Container $new_container = NULL) {
   // We do not use drupal_static() here because we do not have a mechanism by
   // which to reinitialize the stored objects, so a drupal_static_reset() call
   // would leave Drupal in a nonfunctional state.
-  static $container = NULL;
-  if ($rebuild) {
-    $container = NULL;
-  }
+  static $container;
   if (isset($new_container)) {
     $container = $new_container;
   }
-  if (!isset($container)) {
-    // This is only ever used by the installer and by run-tests.sh.
-    // @todo Remove this entire section once these have been converted to use a
-    //   kernel.
-    $container = new ContainerBuilder();
-
-    // Register active configuration storage.
-    $container
-      ->register('config.cachedstorage.storage', 'Drupal\Core\Config\FileStorage')
-      ->addArgument(config_get_config_directory(CONFIG_ACTIVE_DIRECTORY));
-    // @todo Replace this with a cache.factory service plus 'config' argument.
-    $container
-      ->register('cache.config', 'Drupal\Core\Cache\CacheBackendInterface')
-      ->setFactoryClass('Drupal\Core\Cache\CacheFactory')
-      ->setFactoryMethod('get')
-      ->addArgument('config');
-
-    $container
-      ->register('config.storage', 'Drupal\Core\Config\CachedStorage')
-      ->addArgument(new Reference('config.cachedstorage.storage'))
-      ->addArgument(new Reference('cache.config'));
-
-    // Register configuration object factory.
-    $container->register('config.subscriber.globalconf', 'Drupal\Core\EventSubscriber\ConfigGlobalOverrideSubscriber');
-    $container->register('dispatcher', 'Symfony\Component\EventDispatcher\EventDispatcher')
-      ->addMethodCall('addSubscriber', array(new Reference('config.subscriber.globalconf')));
-    $container->register('config.factory', 'Drupal\Core\Config\ConfigFactory')
-      ->addArgument(new Reference('config.storage'))
-      ->addArgument(new Reference('dispatcher'));
-
-    // Register staging configuration storage.
-    $container
-      ->register('config.storage.staging', 'Drupal\Core\Config\FileStorage')
-      ->addArgument(config_get_config_directory(CONFIG_STAGING_DIRECTORY));
-
-    // Register the service for the default database connection.
-    $container->register('database', 'Drupal\Core\Database\Connection')
-      ->setFactoryClass('Drupal\Core\Database\Database')
-      ->setFactoryMethod('getConnection')
-      ->addArgument('default');
-    // Register the KeyValueStore factory.
-    $container
-      ->register('keyvalue', 'Drupal\Core\KeyValueStore\KeyValueFactory')
-      ->addArgument(new Reference('service_container'));
-    $container
-      ->register('keyvalue.database', 'Drupal\Core\KeyValueStore\KeyValueDatabaseFactory')
-      ->addArgument(new Reference('database'));
-
-    $container->register('path.alias_manager', 'Drupal\Core\Path\AliasManager')
-      ->addArgument(new Reference('database'))
-      ->addArgument(new Reference('keyvalue'));
-
-    // Register the EntityManager.
-    $container->register('plugin.manager.entity', 'Drupal\Core\Entity\EntityManager');
-  }
   return $container;
 }
 
diff --git a/core/includes/file.inc b/core/includes/file.inc
index 137dd0d7509d927c809cf922ebf3d896a52af22b..bcd30334d9e2088de10ffa76313553eb94307e3e 100644
--- a/core/includes/file.inc
+++ b/core/includes/file.inc
@@ -5,10 +5,12 @@
  * API for handling file uploads and server file management.
  */
 
+use Drupal\Core\StreamWrapper\LocalStream;
+use Drupal\Component\PhpStorage\MTimeProtectedFastFileStorage;
 use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 use Symfony\Component\HttpFoundation\StreamedResponse;
-use Drupal\Core\StreamWrapper\LocalStream;
+
 /**
  * Stream wrapper bit flags that are the basis for composite types.
  *
@@ -558,7 +560,7 @@ function file_save_htaccess($directory, $private = TRUE) {
 
   if ($private) {
     // Private .htaccess file.
-    $htaccess_lines = "SetHandler Drupal_Security_Do_Not_Remove_See_SA_2006_006\nDeny from all\nOptions None\nOptions +FollowSymLinks";
+    $htaccess_lines = MTimeProtectedFastFileStorage::HTACCESS;
   }
   else {
     // Public .htaccess file.
diff --git a/core/includes/install.core.inc b/core/includes/install.core.inc
index 5366436904ed536b32e5c7da69d54cae2cf3237a..8e0e29c2b090dcdedf8198b33f07b07bdd8f7f31 100644
--- a/core/includes/install.core.inc
+++ b/core/includes/install.core.inc
@@ -288,6 +288,9 @@ function install_begin_request(&$install_state) {
 
   // Determine whether the configuration system is ready to operate.
   $install_state['config_verified'] = install_verify_config_directory(CONFIG_ACTIVE_DIRECTORY) && install_verify_config_directory(CONFIG_STAGING_DIRECTORY);
+  // Check existing settings.php.
+  $install_state['database_verified'] = install_verify_database_settings();
+  $install_state['settings_verified'] = $install_state['config_verified'] && $install_state['database_verified'];
 
   // If it is not, replace the configuration storage with the InstallStorage
   // implementation, for the following reasons:
@@ -309,10 +312,15 @@ function install_begin_request(&$install_state) {
   //   the default configuration provided by the installation profile and
   //   modules (most notably System module). The InstallStorage therefore reads
   //   from the default configuration directories of extensions.
-  // This override is reverted as soon as the config directory has been set up
-  // successfully.
+  // This override is reverted as soon as the config directory and the
+  // database has been set up successfully.
   // @see drupal_install_config_directories()
-  if (!$install_state['config_verified']) {
+  // @see install_settings_form_submit()
+  if ($install_state['settings_verified']) {
+    $kernel = new DrupalKernel('install', FALSE, drupal_classloader(), FALSE);
+    $kernel->boot();
+  }
+  else {
     // @todo Move into a proper Drupal\Core\DependencyInjection\InstallContainerBuilder.
     $container = new ContainerBuilder();
 
@@ -362,10 +370,6 @@ function install_begin_request(&$install_state) {
   // accessing the database before it is set up yet.)
   drupal_maintenance_theme();
 
-  // Check existing settings.php.
-  $install_state['database_verified'] = install_verify_database_settings();
-  $install_state['settings_verified'] = $install_state['config_verified'] && $install_state['database_verified'];
-
   if ($install_state['database_verified']) {
     // Initialize the database system. Note that the connection
     // won't be initialized until it is actually requested.
@@ -1104,11 +1108,6 @@ function install_settings_form_submit($form, &$form_state) {
   // Add the config directories to settings.php.
   drupal_install_config_directories();
 
-  // We have valid configuration directories in settings.php.
-  // Reset the service container, so the config.storage service will use the
-  // actual active storage for installing configuration.
-  drupal_container(NULL, TRUE);
-
   // Indicate that the settings file has been verified, and check the database
   // for the last completed task, now that we have a valid connection. This
   // last step is important since we want to trigger an error if the new
@@ -1500,10 +1499,6 @@ function install_bootstrap_full(&$install_state) {
   // Clear the module list that was overriden earlier in the process.
   // This will allow all freshly installed modules to be loaded.
   module_list_reset();
-
-  // Instantiate the kernel.
-  $kernel = new DrupalKernel('prod', FALSE, drupal_classloader(), FALSE);
-  $kernel->boot();
   drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL);
 }
 
diff --git a/core/includes/install.inc b/core/includes/install.inc
index a2666aec7307bed2843749313135850b5a051f2f..99cfcf6da0687f55af65922c68ea54591c9d1d52 100644
--- a/core/includes/install.inc
+++ b/core/includes/install.inc
@@ -6,6 +6,7 @@
  */
 
 use Drupal\Core\Database\Database;
+use Drupal\Core\DrupalKernel;
 use Drupal\locale\Gettext;
 
 /**
@@ -421,6 +422,9 @@ function drupal_verify_profile($install_state) {
 function drupal_install_system() {
   // Create tables.
   drupal_install_schema('system');
+  // Immediately boot a kernel to have real services ready.
+  $kernel = new DrupalKernel('install', FALSE, drupal_classloader(), FALSE);
+  $kernel->boot();
 
   $system_path = drupal_get_path('module', 'system');
   require_once DRUPAL_ROOT . '/' . $system_path . '/system.install';
diff --git a/core/lib/Drupal/Component/PhpStorage/FileStorage.php b/core/lib/Drupal/Component/PhpStorage/FileStorage.php
index a07c27e9a152e1e245b6b4b1f5fd90a50cd526bd..fcbbb7b00b69fdb29d7626a9eaed49905fe0572e 100644
--- a/core/lib/Drupal/Component/PhpStorage/FileStorage.php
+++ b/core/lib/Drupal/Component/PhpStorage/FileStorage.php
@@ -83,6 +83,10 @@ function writeable() {
    * Implements Drupal\Component\PhpStorage\PhpStorageInterface::deleteAll().
    */
   function deleteAll() {
+    // @todo remove this to properly decouple this class from Drupal.
+    if (!function_exists('file_unmanaged_delete_recursive')) {
+      include_once DRUPAL_ROOT . '/core/includes/file.inc';
+    }
     return file_unmanaged_delete_recursive($this->directory, array(__CLASS__, 'filePreDeleteCallback'));
   }
 
diff --git a/core/lib/Drupal/Component/PhpStorage/MTimeProtectedFastFileStorage.php b/core/lib/Drupal/Component/PhpStorage/MTimeProtectedFastFileStorage.php
index 68a62052d15e1084222005dc5df365c70d2dc8c6..908289aa00c7ca86d5cbb7e08f528da6219f672a 100644
--- a/core/lib/Drupal/Component/PhpStorage/MTimeProtectedFastFileStorage.php
+++ b/core/lib/Drupal/Component/PhpStorage/MTimeProtectedFastFileStorage.php
@@ -40,6 +40,8 @@
  */
 class MTimeProtectedFastFileStorage extends FileStorage {
 
+  const HTACCESS="SetHandler Drupal_Security_Do_Not_Remove_See_SA_2006_006\nDeny from all\nOptions None\nOptions +FollowSymLinks";
+
   /**
    * The secret used in the HMAC.
    *
@@ -144,7 +146,10 @@ protected function ensureDirectory() {
       mkdir($this->directory, 0700, TRUE);
     }
     chmod($this->directory, 0700);
-    file_save_htaccess($this->directory);
+    $htaccess_path =  $this->directory . '/.htaccess';
+    if (!file_exists($htaccess_path) && file_put_contents($htaccess_path, self::HTACCESS)) {
+      @chmod($htaccess_path, 0444);
+    }
   }
 
   /**
diff --git a/core/lib/Drupal/Core/DrupalKernel.php b/core/lib/Drupal/Core/DrupalKernel.php
index f07d081fad4304853c961750691761f0a533242a..ebcf6b2b3bd5bd1e66795e532f7f5c8602f66abf 100644
--- a/core/lib/Drupal/Core/DrupalKernel.php
+++ b/core/lib/Drupal/Core/DrupalKernel.php
@@ -158,11 +158,6 @@ public function boot() {
     }
     $this->initializeContainer();
     $this->booted = TRUE;
-    // @todo Remove this once everything in the bootstrap has been converted to
-    //   services in the DIC.
-    drupal_bootstrap(DRUPAL_BOOTSTRAP_CODE);
-    // Now that full bootstrap is complete, we can dump the container if it
-    // was just rebuilt.
     if ($this->containerNeedsDumping && !$this->dumpDrupalContainer($this->container, $this->getContainerBaseClass())) {
       watchdog('DrupalKernel', 'Container cannot be written to disk');
     }
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/DrupalUnitTestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/DrupalUnitTestBase.php
index 7e9c9600346c9568667a0a95a07c6fd80e8aa626..793c8c0a2a4617e6a9c78ce8c626cf609af5e4fd 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/DrupalUnitTestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/DrupalUnitTestBase.php
@@ -8,6 +8,7 @@
 namespace Drupal\simpletest;
 
 use Drupal\Core\DrupalKernel;
+use Symfony\Component\DependencyInjection\Reference;
 use Drupal\Core\Database\Database;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
@@ -129,6 +130,21 @@ public function containerBuild($container) {
     $conf['keyvalue_default'] = 'keyvalue.memory';
     $container
       ->register('keyvalue.memory', 'Drupal\Core\KeyValueStore\KeyValueMemoryFactory');
+    if (!$container->has('keyvalue')) {
+      // TestBase::setUp puts a completely empty container in
+      // drupal_container() which is somewhat the mirror of the empty
+      // environment being set up. Unit tests need not to waste time with
+      // getting a container set up for them. Drupal Unit Tests might just get
+      // away with a simple container holding the absolute bare minimum. When
+      // a kernel is overridden then there's no need to re-register the keyvalue
+      // service but when a test is happy with the superminimal container put
+      // together here, it still might a keyvalue storage for anything (for 
+      // eg. module_enable) using state() -- that's why a memory service was
+      // added in the first place.
+      $container
+        ->register('keyvalue', 'Drupal\Core\KeyValueStore\KeyValueFactory')
+        ->addArgument(new Reference('service_container'));
+    }
   }
 
   /**
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
index 72ec6287bda6f0494dce2525bce7512066f6465e..93cdbf2f16088d41b0dd6e056040c6c45e067e46 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
@@ -8,6 +8,7 @@
 namespace Drupal\simpletest;
 
 use Drupal\Core\Database\Database;
+use Drupal\Core\DependencyInjection\ContainerBuilder;
 use Drupal\Core\Database\ConnectionNotDefinedException;
 use Drupal\Core\DrupalKernel;
 use ReflectionMethod;
@@ -819,7 +820,9 @@ protected function prepareEnvironment() {
     $this->originalContainer = clone drupal_container();
     $this->originalLanguage = $language_interface;
     $this->originalConfigDirectories = $GLOBALS['config_directories'];
-    $this->originalThemeKey = isset($GLOBALS['theme_key']) ? $GLOBALS['theme_key'] : NULL;
+    if (isset($GLOBALS['theme_key'])) {
+      $this->originalThemeKey = $GLOBALS['theme_key'];
+    }
     $this->originalTheme = isset($GLOBALS['theme']) ? $GLOBALS['theme'] : NULL;
 
     // Save further contextual information.
@@ -873,7 +876,8 @@ protected function prepareEnvironment() {
     }
 
     // Reset and create a new service container.
-    $this->container = drupal_container(NULL, TRUE);
+    $this->container = new ContainerBuilder();
+    drupal_container($this->container);
 
     // Unset globals.
     unset($GLOBALS['theme_key']);
@@ -906,9 +910,6 @@ protected function prepareEnvironment() {
    *   enabled modules to be immediately available in the same request.
    */
   protected function rebuildContainer() {
-    // DrupalKernel expects to merge a fresh bootstrap container, not remerge
-    // what is left over from a prior container build.
-    drupal_container(NULL, TRUE);
     // Create a new DrupalKernel for testing purposes, now that all required
     // modules have been enabled. This also stores a new dependency injection
     // container in drupal_container(). Drupal\simpletest\TestBase::tearDown()
@@ -966,11 +967,13 @@ protected function tearDown() {
     // In case a fatal error occurred that was not in the test process read the
     // log to pick up any fatal errors.
     simpletest_log_read($this->testId, $this->databasePrefix, get_class($this), TRUE);
-    $captured_emails = state()->get('system.test_email_collector') ?: array();
-    $emailCount = count($captured_emails);
-    if ($emailCount) {
-      $message = format_plural($emailCount, '1 e-mail was sent during this test.', '@count e-mails were sent during this test.');
-      $this->pass($message, t('E-mail'));
+    if (($container = drupal_container()) && $container->has('keyvalue')) {
+      $captured_emails = state()->get('system.test_email_collector') ?: array();
+      $emailCount = count($captured_emails);
+      if ($emailCount) {
+        $message = format_plural($emailCount, '1 e-mail was sent during this test.', '@count e-mails were sent during this test.');
+        $this->pass($message, t('E-mail'));
+      }
     }
 
     // Delete temporary files directory.
@@ -985,7 +988,9 @@ protected function tearDown() {
     $databases['default']['default'] = $connection_info['default'];
 
     // Restore original globals.
-    $GLOBALS['theme_key'] = $this->originalThemeKey;
+    if (isset($this->originalThemeKey)) {
+      $GLOBALS['theme_key'] = $this->originalThemeKey;
+    }
     $GLOBALS['theme'] = $this->originalTheme;
 
     // Reset all static variables.
diff --git a/core/modules/system/lib/Drupal/system/Tests/Bootstrap/GetFilenameUnitTest.php b/core/modules/system/lib/Drupal/system/Tests/Bootstrap/GetFilenameUnitTest.php
index 32705bf374ec550643038602b8104452c8476ad8..27ea1d76343280fc283c5d21e74300ccfa28fd45 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Bootstrap/GetFilenameUnitTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Bootstrap/GetFilenameUnitTest.php
@@ -22,24 +22,13 @@ public static function getInfo() {
     );
   }
 
-  function setUp() {
-    parent::setUp();
-
-    // Remove the keyvalue service definition, since this test wants to verify
-    // the filesystem scan fallback of drupal_get_filename().
-    $this->keyvalue_definition = $this->container->getDefinition('keyvalue');
-    $this->container->removeDefinition('keyvalue');
-  }
-
-  function tearDown() {
-    $this->container->setDefinition('keyvalue', $this->keyvalue_definition);
-    parent::tearDown();
-  }
-
   /**
    * Tests that drupal_get_filename() works when the file is not in database.
    */
   function testDrupalGetFilename() {
+    // Assert that the test is meaningful by making sure the keyvalue service
+    // does not exist.
+    $this->assertFalse(drupal_container()->has('keyvalue'), 'The container has no keyvalue service.');
     // Retrieving the location of a module.
     $this->assertIdentical(drupal_get_filename('module', 'php'), 'core/modules/php/php.module', 'Retrieve module location.');
 
diff --git a/core/modules/system/lib/Drupal/system/Tests/DrupalKernel/DrupalKernelTest.php b/core/modules/system/lib/Drupal/system/Tests/DrupalKernel/DrupalKernelTest.php
index c313d8259d1d4ea5a26371597f47b195b09b8b0c..b859c16562b43caff3fc03e524c2bfe7da81f758 100644
--- a/core/modules/system/lib/Drupal/system/Tests/DrupalKernel/DrupalKernelTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/DrupalKernel/DrupalKernelTest.php
@@ -30,11 +30,6 @@ public static function getInfo() {
    * Tests DIC compilation.
    */
   function testCompileDIC() {
-    // Because we'll be instantiating a new kernel during this test, the
-    // container stored in drupal_container() will be updated as a side effect.
-    // We need to be able to restore it to the correct one at the end of this
-    // test.
-    $original_container = drupal_container();
     $classloader = drupal_classloader();
     global $conf;
     $conf['php_storage']['service_container']= array(
@@ -63,9 +58,6 @@ function testCompileDIC() {
       !$refClass->isSubclassOf('Symfony\Component\DependencyInjection\ContainerBuilder');
     $this->assertTrue($is_compiled_container);
 
-    // Reset the container.
-    drupal_container(NULL, TRUE);
-
     // Now use the read-only storage implementation, simulating a "production"
     // environment.
     $conf['php_storage']['service_container']['class'] = 'Drupal\Component\PhpStorage\FileReadOnlyStorage';
@@ -89,9 +81,6 @@ function testCompileDIC() {
     // modules.
     $this->assertFalse($container->has('bundle_test_class'));
 
-    // Reset the container.
-    drupal_container(NULL, TRUE);
-
     // Add another module so that we can test that the new module's bundle is
     // registered to the new container.
     $module_enabled['bundle_test'] = 'bundle_test';
@@ -113,8 +102,5 @@ function testCompileDIC() {
     $classloader = $container->get('class_loader');
     $refClass = new ReflectionClass($classloader);
     $this->assertTrue($refClass->hasMethod('getNamespaces'), 'Container has a classloader');
-
-    // Restore the original container.
-    drupal_container($original_container);
   }
 }
diff --git a/core/modules/system/lib/Drupal/system/Tests/Upgrade/UpgradePathTestBase.php b/core/modules/system/lib/Drupal/system/Tests/Upgrade/UpgradePathTestBase.php
index 21998e2dd5c618b51bd9e1159f464e4c9020b5c4..a62eb90f20140f688ef0fc9fffa349a499b4d7df 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Upgrade/UpgradePathTestBase.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Upgrade/UpgradePathTestBase.php
@@ -134,6 +134,7 @@ protected function setUp() {
     $this->variable_set('site_mail', 'simpletest@example.com');
 
     drupal_set_time_limit($this->timeLimit);
+    $this->rebuildContainer();
     $this->setup = TRUE;
   }
 
diff --git a/core/update.php b/core/update.php
index 8563657a82b61872585a0fb91ac3b720432283a0..984374ea2e86c55dc1352526d4ef463c7e87816b 100644
--- a/core/update.php
+++ b/core/update.php
@@ -464,20 +464,6 @@ function update_check_requirements($skip_warnings = FALSE) {
 drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL);
 drupal_maintenance_theme();
 
-// @todo Remove after converting update.php to use DrupalKernel.
-$container = drupal_container();
-$container->register('database', 'Drupal\Core\Database\Connection')
-  ->setFactoryClass('Drupal\Core\Database\Database')
-  ->setFactoryMethod('getConnection')
-  ->addArgument('default');
-$container->register('lock', 'Drupal\Core\Lock\DatabaseLockBackend');
-$container->register('router.dumper', '\Drupal\Core\Routing\MatcherDumper')
-  ->addArgument(new Reference('database'));
-$container->register('router.builder', 'Drupal\Core\Routing\RouteBuilder')
-  ->addArgument(new Reference('router.dumper'))
-  ->addArgument(new Reference('lock'))
-  ->addArgument(new Reference('dispatcher'));
-
 // Turn error reporting back on. From now on, only fatal errors (which are
 // not passed through the error handler) will cause a message to be printed.
 ini_set('display_errors', TRUE);
diff --git a/index.php b/index.php
index 082276950bfa24f56d659d96a35450ff1daaf0f7..98bcddb9d57db69f2a1fa99cac48fceab0471db8 100644
--- a/index.php
+++ b/index.php
@@ -30,6 +30,11 @@
 // @todo Figure out how best to handle the Kernel constructor parameters.
 $kernel = new DrupalKernel('prod', FALSE, drupal_classloader());
 
+// @todo Remove this once everything in the bootstrap has been
+//   converted to services in the DIC.
+$kernel->boot();
+drupal_bootstrap(DRUPAL_BOOTSTRAP_CODE);
+
 // Create a request object from the HTTPFoundation.
 $request = Request::createFromGlobals();
 $response = $kernel->handle($request)->prepare($request)->send();