diff --git a/_includes/service_container/_my_mailer.rst.inc b/_includes/service_container/_my_mailer.rst.inc
index 1933a23b390..37a20edf4a9 100644
--- a/_includes/service_container/_my_mailer.rst.inc
+++ b/_includes/service_container/_my_mailer.rst.inc
@@ -28,9 +28,6 @@
 
         // app/config/services.php
         use AppBundle\Mailer;
-        use Symfony\Component\DependencyInjection\Definition;
 
-        $container->setDefinition('app.mailer', new Definition(
-            Mailer::class,
-            array('sendmail')
-        ));
+        $container->register('app.mailer', Mailer::class)
+            ->addArgument('sendmail');
diff --git a/components/event_dispatcher.rst b/components/event_dispatcher.rst
index c5f77f70d58..95f74983550 100644
--- a/components/event_dispatcher.rst
+++ b/components/event_dispatcher.rst
@@ -195,7 +195,6 @@ determine which instance is passed.
     a compiler pass called ``RegisterListenersPass()`` in the container builder::
 
         use Symfony\Component\DependencyInjection\ContainerBuilder;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\ParameterBag\ParameterBag;
         use Symfony\Component\DependencyInjection\Reference;
         use Symfony\Component\EventDispatcher\EventDispatcher;
@@ -209,17 +208,15 @@ determine which instance is passed.
         $containerBuilder->register('event_dispatcher', EventDispatcher::class);
 
         // register an event listener
-        $listener = new Definition(\AcmeListener::class);
-        $listener->addTag('kernel.event_listener', array(
-            'event' => 'acme.foo.action',
-            'method' => 'onFooAction',
-        ));
-        $containerBuilder->setDefinition('listener_service_id', $listener);
+        $containerBuilder->register('listener_service_id', \AcmeListener::class)
+            ->addTag('kernel.event_listener', array(
+                'event' => 'acme.foo.action',
+                'method' => 'onFooAction',
+            ));
 
         // register an event subscriber
-        $subscriber = new Definition(\AcmeSubscriber::class);
-        $subscriber->addTag('kernel.event_subscriber');
-        $containerBuilder->setDefinition('subscriber_service_id', $subscriber);
+        $containerBuilder->register('subscriber_service_id', \AcmeSubscriber::class)
+            ->addTag('kernel.event_subscriber');
 
     By default, the listeners pass assumes that the event dispatcher's service
     id is ``event_dispatcher``, that event listeners are tagged with the
diff --git a/components/phpunit_bridge.rst b/components/phpunit_bridge.rst
index 4107c170d46..c21b2ebdd19 100644
--- a/components/phpunit_bridge.rst
+++ b/components/phpunit_bridge.rst
@@ -190,17 +190,18 @@ Use Case
 
 If you have this kind of time-related tests::
 
+    use PHPUnit\Framework\TestCase;
     use Symfony\Component\Stopwatch\Stopwatch;
 
-    class MyTest extends \PHPUnit_Framework_TestCase
+    class MyTest extends TestCase
     {
         public function testSomething()
         {
             $stopwatch = new Stopwatch();
 
-            $stopwatch->start();
+            $stopwatch->start('event_name');
             sleep(10);
-            $duration = $stopwatch->stop();
+            $duration = $stopwatch->stop('event_name')->getDuration();
 
             $this->assertEquals(10, $duration);
         }
@@ -245,12 +246,13 @@ following listener in your PHPUnit configuration:
 As a result, the following is guaranteed to work and is no longer a transient
 test::
 
+    use PHPUnit\Framework\TestCase;
     use Symfony\Component\Stopwatch\Stopwatch;
 
     /**
      * @group time-sensitive
      */
-    class MyTest extends \PHPUnit_Framework_TestCase
+    class MyTest extends TestCase
     {
         public function testSomething()
         {
@@ -297,9 +299,10 @@ Use Case
 Consider the following example that uses the ``checkMX`` option of the ``Email``
 constraint to test the validity of the email domain::
 
+    use PHPUnit\Framework\TestCase;
     use Symfony\Component\Validator\Constraints\Email;
 
-    class MyTest extends \PHPUnit_Framework_TestCase
+    class MyTest extends TestCase
     {
         public function testEmail()
         {
@@ -315,12 +318,13 @@ In order to avoid making a real network connection, add the ``@dns-sensitive``
 annotation to the class and use the ``DnsMock::withMockedHosts()`` to configure
 the data you expect to get for the given hosts::
 
+    use PHPUnit\Framework\TestCase;
     use Symfony\Component\Validator\Constraints\Email;
 
     /**
      * @group dns-sensitive
      */
-    class MyTest extends \PHPUnit_Framework_TestCase
+    class MyTest extends TestCase
     {
         public function testEmails()
         {
diff --git a/controller/error_pages.rst b/controller/error_pages.rst
index 9801b8934cd..e42997404ab 100644
--- a/controller/error_pages.rst
+++ b/controller/error_pages.rst
@@ -296,13 +296,12 @@ In that case, you might want to override one or both of the ``showAction()`` and
             // app/config/services.php
             use AppBundle\Controller\CustomExceptionController;
             use Symfony\Component\DependencyInjection\Reference;
-            use Symfony\Component\DependencyInjection\Definition;
 
-            $definition = new Definition(CustomExceptionController::class, array(
-                new Reference('twig'),
-                '%kernel.debug%'
-            ));
-            $container->setDefinition('app.exception_controller', $definition);
+            $container->register('app.exception_controller', CustomExceptionController::class)
+                ->setArguments(array(
+                    new Reference('twig'),
+                    '%kernel.debug%',
+                ));
 
     And then configure ``twig.exception_controller`` using the controller as
     services syntax (e.g. ``app.exception_controller:showAction``).
diff --git a/controller/upload_file.rst b/controller/upload_file.rst
index e91db665b16..7ffe7503d97 100644
--- a/controller/upload_file.rst
+++ b/controller/upload_file.rst
@@ -283,13 +283,10 @@ Then, define a service for this class:
 
         // app/config/services.php
         use AppBundle\FileUploader;
-        use Symfony\Component\DependencyInjection\Definition;
 
         // ...
-        $container->setDefinition('app.brochure_uploader', new Definition(
-            FileUploader::class,
-            array('%brochures_directory%')
-        ));
+        $container->register('app.brochure_uploader', FileUploader::class)
+            ->addArgument('%brochures_directory%');
 
 Now you're ready to use this service in the controller::
 
@@ -411,21 +408,17 @@ Now, register this class as a Doctrine listener:
 
         // app/config/services.php
         use AppBundle\EventListener\BrochureUploaderListener;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
         // ...
-        $definition = new Definition(
-            BrochureUploaderListener::class,
-            array(new Reference('brochures_directory'))
-        );
-        $definition->addTag('doctrine.event_listener', array(
-            'event' => 'prePersist',
-        ));
-        $definition->addTag('doctrine.event_listener', array(
-            'event' => 'preUpdate',
-        ));
-        $container->setDefinition('app.doctrine_brochure_listener', $definition);
+        $container->register('app.doctrine_brochure_listener', BrochureUploaderListener::class)
+            ->addArgument(new Reference('brochures_directory'))
+            ->addTag('doctrine.event_listener', array(
+                'event' => 'prePersist',
+            ))
+            ->addTag('doctrine.event_listener', array(
+                'event' => 'prePersist',
+            ));
 
 This listener is now automatically executed when persisting a new Product
 entity. This way, you can remove everything related to uploading from the
diff --git a/doctrine/event_listeners_subscribers.rst b/doctrine/event_listeners_subscribers.rst
index 587ba9f3d28..911b3cb6b4a 100644
--- a/doctrine/event_listeners_subscribers.rst
+++ b/doctrine/event_listeners_subscribers.rst
@@ -84,7 +84,6 @@ managers that use this connection.
         use AppBundle\EventListener\SearchIndexer;
         use AppBundle\EventListener\SearchIndexer2;
         use AppBundle\EventListener\SearchIndexerSubscriber;
-        use Symfony\Component\DependencyInjection\Definition;
 
         $container->loadFromExtension('doctrine', array(
             'dbal' => array(
diff --git a/doctrine/mongodb_session_storage.rst b/doctrine/mongodb_session_storage.rst
index d96777620f8..fcfecfe3dd2 100644
--- a/doctrine/mongodb_session_storage.rst
+++ b/doctrine/mongodb_session_storage.rst
@@ -77,7 +77,6 @@ need to change/add some parameters in the main configuration file:
     .. code-block:: php
 
         use Symfony\Component\DependencyInjection\Reference;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\HttpFoundation\Session\Storage\Handler\MongoDbSessionHandler;
 
         $container->loadFromExtension('framework', array(
@@ -89,20 +88,19 @@ need to change/add some parameters in the main configuration file:
             ),
         ));
 
-        $container->setDefinition('mongo_client', new Definition(
-            \MongoClient::class,
-            array(
+        $container->register('mongo_client', \MongoClient::class)
+            ->setArguments(array(
                 // if using a username and password
                 array('mongodb://%mongodb_username%:%mongodb_password%@%mongodb_host%:27017'),
                 // if not using a username and password
                 array('mongodb://%mongodb_host%:27017'),
-            )
-        ));
+            ));
 
-        $container->setDefinition('session.handler.mongo', new Definition(
-            MongoDbSessionHandler::class,
-            array(new Reference('mongo_client'), '%mongo.session.options%')
-        ));
+        $container->register('session.handler.mongo', MongoDbSessionHandler::class)
+            ->setArguments(array(
+                new Reference('mongo_client'),
+                '%mongo.session.options%',
+            ));
 
 The parameters used above should be defined somewhere in your application, often in your main
 parameters configuration:
@@ -149,7 +147,6 @@ parameters configuration:
     .. code-block:: php
 
         use Symfony\Component\DependencyInjection\Reference;
-        use Symfony\Component\DependencyInjection\Definition;
 
         $container->setParameter('mongo.session.options', array(
             'database'   => 'session_db', // your MongoDB database name
diff --git a/doctrine/pdo_session_storage.rst b/doctrine/pdo_session_storage.rst
index 428eb5e0b99..f318d4ccda1 100644
--- a/doctrine/pdo_session_storage.rst
+++ b/doctrine/pdo_session_storage.rst
@@ -52,6 +52,8 @@ To use it, you just need to change some parameters in the main configuration fil
 
         // app/config/config.php
 
+        use Symfony\Component\HttpFoundation\Session\Storage\Handler\PdoSessionHandler;
+
         // ...
         $container->loadFromExtension('framework', array(
             // ...
@@ -61,11 +63,11 @@ To use it, you just need to change some parameters in the main configuration fil
             ),
         ));
 
-        $storageDefinition = new Definition(PdoSessionHandler::class, array(
-            'mysql:dbname=mydatabase',
-            array('db_username' => 'myuser', 'db_password' => 'mypassword')
-        ));
-        $container->setDefinition('session.handler.pdo', $storageDefinition);
+        $container->register('session.handler.pdo', PdoSessionHandler::class)
+            ->setArguments(array(
+                'mysql:dbname=mydatabase',
+                array('db_username' => 'myuser', 'db_password' => 'mypassword'),
+            ));
 
 Configuring the Table and Column Names
 --------------------------------------
@@ -106,15 +108,14 @@ a second array argument to ``PdoSessionHandler``:
 
         // app/config/config.php
 
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\HttpFoundation\Session\Storage\Handler\PdoSessionHandler;
         // ...
 
-        $storageDefinition = new Definition(PdoSessionHandler::class, array(
-            'mysql:dbname=mydatabase',
-            array('db_table' => 'sessions', 'db_username' => 'myuser', 'db_password' => 'mypassword')
-        ));
-        $container->setDefinition('session.handler.pdo', $storageDefinition);
+        $container->register('session.handler.pdo', PdoSessionHandler::class)
+            ->setArguments(array(
+                'mysql:dbname=mydatabase',
+                array('db_table' => 'sessions', 'db_username' => 'myuser', 'db_password' => 'mypassword'),
+            ));
 
 These are parameters that you must configure:
 
diff --git a/event_dispatcher/before_after_filters.rst b/event_dispatcher/before_after_filters.rst
index 08acc19ef7f..b36620bc5f8 100644
--- a/event_dispatcher/before_after_filters.rst
+++ b/event_dispatcher/before_after_filters.rst
@@ -173,14 +173,13 @@ your listener to be called just before any controller is executed.
 
         // app/config/services.php
         use AppBundle\EventListener\TokenListener;
-        use Symfony\Component\DependencyInjection\Definition;
 
-        $listener = new Definition(TokenListener::class, array('%tokens%'));
-        $listener->addTag('kernel.event_listener', array(
-            'event'  => 'kernel.controller',
-            'method' => 'onKernelController'
-        ));
-        $container->setDefinition('app.tokens.action_listener', $listener);
+        $container->register('app.tokens.action_listener', TokenListener::class)
+            ->addArgument('%tokens%')
+            ->addTag('kernel.event_listener', array(
+                'event'  => 'kernel.controller',
+                'method' => 'onKernelController',
+            ));
 
 With this configuration, your ``TokenListener`` ``onKernelController()`` method
 will be executed on each request. If the controller that is about to be executed
@@ -271,18 +270,17 @@ event:
 
         // app/config/services.php
         use AppBundle\EventListener\TokenListener;
-        use Symfony\Component\DependencyInjection\Definition;
 
-        $listener = new Definition(TokenListener::class, array('%tokens%'));
-        $listener->addTag('kernel.event_listener', array(
-            'event'  => 'kernel.controller',
-            'method' => 'onKernelController'
-        ));
-        $listener->addTag('kernel.event_listener', array(
-            'event'  => 'kernel.response',
-            'method' => 'onKernelResponse'
-        ));
-        $container->setDefinition('app.tokens.action_listener', $listener);
+        $container->register('app.tokens.action_listener', TokenListener::class)
+            ->addArgument('%tokens%')
+            ->addTag('kernel.event_listener', array(
+                'event'  => 'kernel.controller',
+                'method' => 'onKernelController',
+            ))
+            ->addTag('kernel.event_listener', array(
+                'event'  => 'kernel.response',
+                'method' => 'onKernelResponse',
+            ));
 
 That's it! The ``TokenListener`` is now notified before every controller is
 executed (``onKernelController()``) and after every controller returns a response
diff --git a/form/create_custom_field_type.rst b/form/create_custom_field_type.rst
index ec653ddb989..09004317079 100644
--- a/form/create_custom_field_type.rst
+++ b/form/create_custom_field_type.rst
@@ -323,15 +323,10 @@ the ``genders`` parameter value as the first argument to its to-be-created
 
         // src/AppBundle/Resources/config/services.php
         use AppBundle\Form\Type\GenderType;
-        use Symfony\Component\DependencyInjection\Definition;
-
-        $container
-            ->setDefinition('app.form.type.gender', new Definition(
-                GenderType::class,
-                array('%genders%')
-            ))
-            ->addTag('form.type')
-        ;
+
+        $container->register('app.form.type.gender', GenderType::class)
+            ->addArgument('%genders%')
+            ->addTag('form.type');
 
 .. tip::
 
diff --git a/form/data_transformers.rst b/form/data_transformers.rst
index 2dc98fc71db..d25be612166 100644
--- a/form/data_transformers.rst
+++ b/form/data_transformers.rst
@@ -458,19 +458,12 @@ it's recognized as a custom field type:
 
         // app/config/services.php
         use AppBundle\Form\IssueSelectorType;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
         // ...
 
-        $container
-            ->setDefinition('app.type.issue_selector', new Definition(
-                IssueSelectorType::class,
-                array(
-                    new Reference('doctrine.orm.entity_manager'),
-                )
-            ))
-            ->addTag('form.type')
-        ;
+        $container->register('app.type.issue_selector', IssueSelectorType::class)
+            ->addArgument(new Reference('doctrine.orm.entity_manager'))
+            ->addTag('form.type');
 
 Now, whenever you need to use your special ``issue_selector`` field type,
 it's quite easy::
diff --git a/form/dynamic_form_modification.rst b/form/dynamic_form_modification.rst
index 9de0e7fc690..d948f567217 100644
--- a/form/dynamic_form_modification.rst
+++ b/form/dynamic_form_modification.rst
@@ -362,12 +362,9 @@ you need to register it as a service and tag it with :ref:`form.type <dic-tags-f
         use AppBundle\Form\Type\FriendMessageFormType;
         use Symfony\Component\DependencyInjection\Reference;
 
-        $definition = new Definition(FriendMessageFormType::class, array(
-            new Reference('security.token_storage')
-        ));
-        $definition->addTag('form.type');
-
-        $container->setDefinition('app.form.friend_message', $definition);
+        $container->register('app.form.friend_message', FriendMessageFormType::class)
+            ->addArgument(new Reference('security.token_storage'))
+            ->addTag('form.type');
 
 .. versionadded:: 3.3
     Prior to Symfony 3.3, you needed to define form type services as ``public``.
diff --git a/form/form_dependencies.rst b/form/form_dependencies.rst
index 6d14a914b6b..b792c4b67f2 100644
--- a/form/form_dependencies.rst
+++ b/form/form_dependencies.rst
@@ -124,16 +124,11 @@ Next, register this as a service and tag it with ``form.type``:
 
         // src/AppBundle/Resources/config/services.php
         use AppBundle\Form\TaskType;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
-        $container
-            ->setDefinition('app.form.type.task', new Definition(
-                TaskType::class,
-                array(new Reference('doctrine.orm.entity_manager'))
-            ))
-            ->addTag('form.type')
-        ;
+        $container->register('app.form.type.task', TaskType::class)
+            ->addArgument(new Reference('doctrine.orm.entity_manager'))
+            ->addTag('form.type');
 
 .. versionadded:: 3.3
     Prior to Symfony 3.3, you needed to define form type services as ``public``.
diff --git a/profiler/matchers.rst b/profiler/matchers.rst
index ee18e2524ad..b0b8dae47f3 100644
--- a/profiler/matchers.rst
+++ b/profiler/matchers.rst
@@ -47,7 +47,7 @@ configuration:
                 <!-- ... -->
                 <framework:profiler>
                     <framework:matcher ip="168.0.0.1" />
-                </framework:profiler>    
+                </framework:profiler>
             </framework:config>
         </container>
 
@@ -134,16 +134,11 @@ won't use it directly:
 
         // app/config/services.php
         use AppBundle\Profiler\SuperAdminMatcher;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
-        $definition = new Definition(
-            SuperAdminMatcher::class,
-            array(new Reference('security.authorization_checker'))
-        );
-        $definition->setPublic(false);
-
-        $container->setDefinition('app.super_admin_matcher', $definition);
+        $container->register('app.super_admin_matcher', SuperAdminMatcher::class)
+            ->addArgument(new Reference('security.authorization_checker'))
+            ->setPublic(false);
 
 Once the service is registered, the only thing left to do is configure the
 profiler to use this service as the matcher:
@@ -176,7 +171,7 @@ profiler to use this service as the matcher:
                 <!-- ... -->
                 <framework:profiler>
                     <framework:matcher service="app.super_admin_matcher" />
-                </framework:profiler>    
+                </framework:profiler>
             </framework:config>
         </container>
 
diff --git a/reference/dic_tags.rst b/reference/dic_tags.rst
index 226a7d6220b..d33d8198e1b 100644
--- a/reference/dic_tags.rst
+++ b/reference/dic_tags.rst
@@ -729,14 +729,11 @@ channel when injecting the logger in a service.
     .. code-block:: php
 
         use AppBundle\Log\CustomLogger;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
-        $definition = new Definition(CustomLogger::class, array(
-            new Reference('logger'),
-        ));
-        $definition->addTag('monolog.logger', array('channel' => 'acme'));
-        $container->setDefinition('app.custom_logger', $definition);
+        $container->register('app.custom_logger', CustomLogger::class)
+            ->addArgument(new Reference('logger'))
+            ->addTag('monolog.logger', array('channel' => 'acme'));
 
 .. tip::
 
diff --git a/security.rst b/security.rst
index df6b7f716dd..aa8f2e8b4aa 100644
--- a/security.rst
+++ b/security.rst
@@ -25,6 +25,7 @@ like :ref:`logging out <security-logging-out>` and
 :doc:`encoding user passwords </security/password_encoding>`.
 
 .. _security-firewalls:
+.. _firewalls-authentication:
 
 1) Initial security.yml Setup (Authentication)
 ----------------------------------------------
@@ -450,6 +451,7 @@ If you'd like to load your users via the Doctrine ORM, that's easy! See
 :doc:`/security/entity_provider` for all the details.
 
 .. _security-encoding-user-password:
+.. _encoding-the-user-s-password:
 
 C) Encoding the User's Password
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/security/api_key_authentication.rst b/security/api_key_authentication.rst
index ab6ff09fe58..6672c700b7c 100644
--- a/security/api_key_authentication.rst
+++ b/security/api_key_authentication.rst
@@ -346,14 +346,12 @@ First, register it as a service.
 
         // app/config/config.php
         use AppBundle\Security\ApiKeyAuthenticator;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
         // ...
 
-        $definition = new Definition(ApiKeyAuthenticator::class);
-        $definition->setPublic(false);
-        $container->setDefinition('apikey_authenticator', $definition);
+        $container->register('apikey_authenticator', ApiKeyAuthenticator::class)
+            ->setPublic(false);
 
 Now, activate it and your custom user provider (see :doc:`/security/custom_provider`)
 in the ``firewalls`` section of your security configuration
@@ -436,7 +434,7 @@ If you have defined ``access_control``, make sure to add a new entry:
         # app/config/security.yml
         security:
             # ...
-            
+
             access_control:
                 - { path: ^/api, roles: ROLE_API }
 
@@ -737,15 +735,12 @@ service:
 
         // app/config/config.php
         use AppBundle\Security\ApiKeyAuthenticator;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
         // ...
 
-        $definition = new Definition(ApiKeyAuthenticator::class, array(
-            new Reference('security.http_utils')
-        ));
-        $definition->setPublic(false);
-        $container->setDefinition('apikey_authenticator', $definition);
+        $container->register('apikey_authenticator', ApiKeyAuthenticator::class)
+            ->addArgument(new Reference('security.http_utils'))
+            ->setPublic(false);
 
 That's it! Have fun!
diff --git a/security/custom_authentication_provider.rst b/security/custom_authentication_provider.rst
index b6d8587ef01..ebc5cec983f 100644
--- a/security/custom_authentication_provider.rst
+++ b/security/custom_authentication_provider.rst
@@ -261,13 +261,13 @@ the ``PasswordDigest`` header value matches with the user's password.
 
             // Try to fetch the cache item from pool
             $cacheItem = $this->cachePool->getItem(md5($nonce));
-            
+
             // Validate that the nonce is *not* in cache
             // if it is, this could be a replay attack
             if ($cacheItem->isHit()) {
                 throw new NonceExpiredException('Previously used nonce detected');
             }
-            
+
             // Store the item in cache for 5 minutes
             $cacheItem->set(null)->expiresAfter(300);
             $this->cachePool->save($cacheItem);
@@ -451,22 +451,21 @@ to service ids that do not exist yet: ``wsse.security.authentication.provider``
         // app/config/services.php
         use AppBundle\Security\Authentication\Provider\WsseProvider;
         use AppBundle\Security\Firewall\WsseListener;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
-        $definition = new Definition(WsseProvider::class, array(
-            '', // User Provider
-            new Reference('cache.app'),
-        ));
-        $definition->setPublic(false);
-        $container->setDefinition('wsse.security.authentication.provider', $definition)
-
-        $definition = new Definition(WsseListener::class, array(
-            new Reference('security.token_storage'),
-            new Reference('security.authentication.manager'),
-        ));
-        $definition->setPublic(false);
-        $container->setDefinition('wsse.security.authentication.listener', $definition);
+        $container->register('wsse.security.authentication.provider', WsseProvider::class)
+            ->setArguments(array(
+                '', // User Provider
+                new Reference('cache.app'),
+            ))
+            ->setPublic(false);
+
+        $container->register('wsse.security.authentication.listener', WsseListener::class)
+            ->setArguments(array(
+                new Reference('security.token_storage'),
+                new Reference('security.authentication.manager'),
+            ))
+            ->setPublic(false);
 
 Now that your services are defined, tell your security context about your
 factory in your bundle class:
diff --git a/security/custom_password_authenticator.rst b/security/custom_password_authenticator.rst
index 4eafb27e331..b6fde008eef 100644
--- a/security/custom_password_authenticator.rst
+++ b/security/custom_password_authenticator.rst
@@ -179,15 +179,12 @@ Now, configure your ``TimeAuthenticator`` as a service:
 
         // app/config/config.php
         use AppBundle\Security\TimeAuthenticator;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
-        
+
         // ...
 
-        $container->setDefinition('time_authenticator', new Definition(
-            TimeAuthenticator::class,
-            array(new Reference('security.password_encoder'))
-        ));
+        $container->register('time_authenticator', TimeAuthenticator::class)
+            ->addArgument(new Reference('security.password_encoder'));
 
 Then, activate it in the ``firewalls`` section of the security configuration
 using the ``simple_form`` key:
diff --git a/security/custom_provider.rst b/security/custom_provider.rst
index cba1d6f2374..21c467e7cba 100644
--- a/security/custom_provider.rst
+++ b/security/custom_provider.rst
@@ -201,7 +201,6 @@ Now you make the user provider available as a service:
 
         // app/config/services.php
         use AppBundle\Security\User\WebserviceUserProvider;
-        use Symfony\Component\DependencyInjection\Definition;
 
         $container->register('app.webservice_user_provider', WebserviceUserProvider::class);
 
diff --git a/security/securing_services.rst b/security/securing_services.rst
index a42f02ee5d5..b84b39092ab 100644
--- a/security/securing_services.rst
+++ b/security/securing_services.rst
@@ -96,13 +96,10 @@ Then in your service configuration, you can inject the service:
 
         // app/config/services.php
         use AppBundle\Newsletter\NewsletterManager;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
-        $container->setDefinition('newsletter_manager', new Definition(
-            NewsletterManager::class,
-            array(new Reference('security.authorization_checker'))
-        ));
+        $container->register('newsletter_manager', NewsletterManager::class)
+            ->addArgument(new Reference('security.authorization_checker'));
 
 The injected service can then be used to perform the security check when the
 ``sendNewsletter()`` method is called::
@@ -179,15 +176,10 @@ the :ref:`sidebar <securing-services-annotations-sidebar>` below):
 
         // app/config/services.php
         use AppBundle\Newsletter\NewsletterManager;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
-        $definition = new Definition(
-            NewsletterManager::class,
-            // ...
-        ));
-        $definition->addTag('security.secure_service');
-        $container->setDefinition('newsletter_manager', $definition);
+        $container->register('newsletter_manager', NewsletterManager::class)
+            ->addTag('security.secure_service');
 
 You can then achieve the same results as above using an annotation::
 
diff --git a/service_container.rst b/service_container.rst
index ea756eb7836..3f45d1fbf67 100644
--- a/service_container.rst
+++ b/service_container.rst
@@ -179,8 +179,8 @@ the service container *how* to instantiate it:
 
         // app/config/services.php
         // _defaults and loading entire directories is not possible with PHP configuration
-        // you need to define your servicess one-by-one
-        use AppBundle/Service/MessageGenerator;
+        // you need to define your services one-by-one
+        use AppBundle\Service\MessageGenerator;
 
         $container->autowire(MessageGenerator::class)
             ->setAutoconfigured(true)
@@ -220,7 +220,7 @@ You can also fetch a service directly from the container via its "id", which wil
 be its class name in this case::
 
     use AppBundle\Service\MessageGenerator;
-    
+
     // accessing services like this only works if you extend Controller
     class ProductController extend Controller
     {
@@ -469,7 +469,7 @@ pass here. No problem! In your configuration, you can explicitly set this argume
 
         // app/config/services.php
         use AppBundle\Updates\SiteUpdateManager;
-        
+
         // _defaults and importing directories does not work in PHP
         // but registering a service explicitly does
         $container->autowire(SiteUpdateManager::class)
@@ -801,7 +801,7 @@ from the container::
     public function newAction(MessageGenerator $messageGenerator)
     {
         // type-hinting it as an argument DOES work
-    
+
         // but accessing it directly from the container does NOT Work
         $this->container->get(MessageGenerator::class);
     }
diff --git a/service_container/alias_private.rst b/service_container/alias_private.rst
index c2a61b056b8..ef89553b76f 100644
--- a/service_container/alias_private.rst
+++ b/service_container/alias_private.rst
@@ -50,11 +50,9 @@ public (i.e. private):
     .. code-block:: php
 
         use Example\Foo;
-        use Symfony\Component\DependencyInjection\Definition;
 
-        $definition = new Definition(Foo::class);
-        $definition->setPublic(false);
-        $container->setDefinition('foo', $definition);
+        $container->register('foo', Foo::class)
+            ->setPublic(false);
 
 What makes private services special is that, since the container knows that the
 service will never be requested from outside, it can optimize whether and how it
@@ -113,11 +111,10 @@ services.
     .. code-block:: php
 
         use AppBundle\Mail\PhpMailer;
-        use Symfony\Component\DependencyInjection\Definition;
 
-        $container->setDefinition('app.phpmailer', new Definition(PhpMailer::class));
+        $container->register('app.phpmailer', PhpMailer::class);
 
-        $containerBuilder->setAlias('app.mailer', 'app.phpmailer');
+        $container->setAlias('app.mailer', 'app.phpmailer');
 
 This means that when using the container directly, you can access the
 ``app.phpmailer`` service by asking for the ``app.mailer`` service like this::
diff --git a/service_container/calls.rst b/service_container/calls.rst
index f14292c2cf5..b5c6aa00bcc 100644
--- a/service_container/calls.rst
+++ b/service_container/calls.rst
@@ -62,7 +62,6 @@ To configure the container to call the ``setLogger`` method, use the ``calls`` k
 
         // app/config/services.php
         use AppBundle\Service\MessageGenerator;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
         $container->register('app.message_generator', 'AppBundle\Service\MessageGenerator')
diff --git a/service_container/configurators.rst b/service_container/configurators.rst
index 6c4a3dae5cd..6777821e2a5 100644
--- a/service_container/configurators.rst
+++ b/service_container/configurators.rst
@@ -173,7 +173,6 @@ You can configure the service configurator using the ``configurator`` option:
         use AppBundle\Mail\EmailFormatterManager;
         use AppBundle\Mail\GreetingCardManager;
         use AppBundle\Mail\NewsletterManager;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
         // ...
@@ -182,13 +181,11 @@ You can configure the service configurator using the ``configurator`` option:
 
         $container->register('app.newsletter_manager', NewsletterManager::class)
             ->addArgument(new Reference('mailer'))
-            ->setConfigurator(array(new Reference('app.email_configurator'), 'configure'))
-        ;
+            ->setConfigurator(array(new Reference('app.email_configurator'), 'configure'));
 
         $container->register('app.greeting_card_manager', GreetingCardManager::class)
             ->addArgument(new Reference('mailer'))
-            ->setConfigurator(array(new Reference('app.email_configurator'), 'configure'))
-        ;
+            ->setConfigurator(array(new Reference('app.email_configurator'), 'configure'));
 
 
 .. versionadded:: 3.2
diff --git a/service_container/definitions.rst b/service_container/definitions.rst
index cb894ad3b2d..6f214843edd 100644
--- a/service_container/definitions.rst
+++ b/service_container/definitions.rst
@@ -31,7 +31,7 @@ There are some helpful methods for working with the service definitions::
     // get the definition with the "app.user_config_manager" ID or alias
     $definition = $container->findDefinition('app.user_config_manager');
 
-    // add a new "app.number_generator" definitions
+    // add a new "app.number_generator" definition
     $definition = new Definition(\AppBundle\NumberGenerator::class);
     $container->setDefinition('app.number_generator', $definition);
 
diff --git a/service_container/expression_language.rst b/service_container/expression_language.rst
index 1b66fd6c672..100d06b4e93 100644
--- a/service_container/expression_language.rst
+++ b/service_container/expression_language.rst
@@ -51,13 +51,10 @@ of the new ``mailer_configuration`` service? One way is to use an expression:
 
         // app/config/config.php
         use AppBundle\Mailer;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\ExpressionLanguage\Expression;
 
-        $container->setDefinition('my_mailer', new Definition(
-            Mailer::class,
-            array(new Expression('service("mailer_configuration").getMailerMethod()'))
-        ));
+        $container->register('my_mailer', Mailer::class)
+            ->addArgument(new Expression('service("mailer_configuration").getMailerMethod()'));
 
 To learn more about the expression language syntax, see :doc:`/components/expression_language/syntax`.
 
@@ -99,15 +96,12 @@ via a ``container`` variable. Here's another example:
     .. code-block:: php
 
         use AppBundle\Mailer;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\ExpressionLanguage\Expression;
 
-        $container->setDefinition('my_mailer', new Definition(
-            Mailer::class,
-            array(new Expression(
+        $container->register('my_mailer', Mailer::class)
+            ->addArgument(new Expression(
                 "container.hasParameter('some_param') ? parameter('some_param') : 'default_value'"
-            ))
-        ));
+            ));
 
 Expressions can be used in ``arguments``, ``properties``, as arguments with
 ``configurator`` and as arguments to ``calls`` (method calls).
diff --git a/service_container/factories.rst b/service_container/factories.rst
index f7b306af4d7..dbfa4cbbd2c 100644
--- a/service_container/factories.rst
+++ b/service_container/factories.rst
@@ -66,14 +66,11 @@ configure the service container to use the
 
         use AppBundle\Email\NewsletterManager;
         use AppBundle\Email\NewsletterManagerStaticFactory;
-        use Symfony\Component\DependencyInjection\Definition;
         // ...
 
-        $definition = new Definition(NewsletterManager::class);
-        // call the static method
-        $definition->setFactory(array(NewsletterManagerStaticFactory::class, 'createNewsletterManager'));
-
-        $container->setDefinition('app.newsletter_manager', $definition);
+        $container->register('app.newsletter_manager', \AppBundle\NumberGenerator::class)
+            // call the static method
+            ->setFactory(array(NewsletterManagerStaticFactory::class, 'createNewsletterManager'));
 
 .. note::
 
@@ -134,20 +131,16 @@ Configuration of the service container then looks like this:
 
         use AppBundle\Email\NewsletterManager;
         use AppBundle\Email\NewsletterManagerFactory;
-        use Symfony\Component\DependencyInjection\Definition;
         // ...
 
         $container->register('app.newsletter_manager_factory', NewsletterManagerFactory::class);
 
-        $newsletterManager = new Definition(NewsletterManager::class);
-
-        // call a method on the specified factory service
-        $newsletterManager->setFactory(array(
-            new Reference('app.newsletter_manager_factory'),
-            'createNewsletterManager'
-        ));
-
-        $container->setDefinition('app.newsletter_manager', $newsletterManager);
+        $container->register('app.newsletter_manager', NewsletterManager::class)
+            // call a method on the specified factory service
+            ->setFactory(array(
+                new Reference('app.newsletter_manager_factory'),
+                'createNewsletterManager',
+            ));
 
 .. note::
 
@@ -212,14 +205,11 @@ method in the previous example takes the ``templating`` service as an argument:
 
         use AppBundle\Email\NewsletterManager;
         use Symfony\Component\DependencyInjection\Reference;
-        use Symfony\Component\DependencyInjection\Definition;
 
         // ...
-        $newsletterManager = new Definition(NewsletterManager::class, array(
-            new Reference('templating')
-        ));
-        $newsletterManager->setFactory(array(
-            new Reference('app.newsletter_manager_factory'),
-            'createNewsletterManager'
-        ));
-        $container->setDefinition('app.newsletter_manager', $newsletterManager);
+        $container->register('app.newsletter_manager', NewsletterManager::class)
+            ->addArgument(new Reference('templating'))
+            ->setFactory(array(
+                new Reference('app.newsletter_manager_factory'),
+                'createNewsletterManager',
+            ));
diff --git a/service_container/import.rst b/service_container/import.rst
index 28e1fc10196..75fa0722ad1 100644
--- a/service_container/import.rst
+++ b/service_container/import.rst
@@ -76,14 +76,11 @@ service files:
 
         // app/config/services/mailer.php
         use AppBundle\Mailer;
-        use Symfony\Component\DependencyInjection\Definition;
 
         $container->setParameter('app.mailer.transport', 'sendmail');
 
-        $container->setDefinition('app.mailer', new Definition(
-            Mailer::class,
-            array('%app.mailer.transport%')
-        ));
+        $container->register('app.mailer', Mailer::class)
+            ->addArgument('%app.mailer.transport%');
 
 The definition itself hasn't changed, only its location. To make the service
 container load the definitions in this resource file, use the ``imports`` key
diff --git a/service_container/injection_types.rst b/service_container/injection_types.rst
index 7be7c7e41bd..1cad6337089 100644
--- a/service_container/injection_types.rst
+++ b/service_container/injection_types.rst
@@ -67,14 +67,11 @@ service container configuration:
     .. code-block:: php
 
         use AppBundle\Mail\NewsletterManager;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
         // ...
-        $container->setDefinition('app.newsletter_manager', new Definition(
-            NewsletterManager::class,
-            array(new Reference('mailer'))
-        ));
+        $container->register('app.newsletter_manager', NewsletterManager::class)
+            ->addArgument(new Reference('mailer'));
 
 .. tip::
 
@@ -152,13 +149,11 @@ that accepts the dependency::
     .. code-block:: php
 
         use AppBundle\Mail\NewsletterManager;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
         // ...
         $container->register('app.newsletter_manager', NewsletterManager::class)
-            ->addMethodCall('setMailer', array(new Reference('mailer')))
-        ;
+            ->addMethodCall('setMailer', array(new Reference('mailer')));
 
 This time the advantages are:
 
@@ -223,13 +218,11 @@ Another possibility is just setting public fields of the class directly::
     .. code-block:: php
 
         use AppBundle\Mail\NewsletterManager;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
 
         // ...
         $container->register('newsletter_manager', NewsletterManager::class)
-            ->setProperty('mailer', new Reference('mailer'))
-        ;
+            ->setProperty('mailer', new Reference('mailer'));
 
 There are mainly only disadvantages to using property injection, it is similar
 to setter injection but with these additional important problems:
diff --git a/service_container/lazy_services.rst b/service_container/lazy_services.rst
index 87078694a4e..36b3798bd56 100644
--- a/service_container/lazy_services.rst
+++ b/service_container/lazy_services.rst
@@ -67,12 +67,9 @@ You can mark the service as ``lazy`` by manipulating its definition:
     .. code-block:: php
 
         use AppBundle\Twig\AppExtension;
-        use Symfony\Component\DependencyInjection\Definition;
 
-        $definition = new Definition(AppExtension::class);
-        $definition->setLazy(true);
-
-        $container->setDefinition('app.twig_extension', $definition);
+        $container->register('app.twig_extension', AppExtension::class)
+            ->setLazy(true);
 
 Once you inject the service into another service, a virtual `proxy`_ with the
 same signature of the class representing the service should be injected. The
diff --git a/service_container/optional_dependencies.rst b/service_container/optional_dependencies.rst
index a5525b5dbb1..126b70eb00c 100644
--- a/service_container/optional_dependencies.rst
+++ b/service_container/optional_dependencies.rst
@@ -39,21 +39,16 @@ if the service does not exist:
 
         // app/config/services.php
         use AppBundle\Newsletter\NewsletterManager;
-        use Symfony\Component\DependencyInjection\Definition;
         use Symfony\Component\DependencyInjection\Reference;
         use Symfony\Component\DependencyInjection\ContainerInterface;
 
-        $container->setDefinition('app.mailer', ...);
+        $container->register('app.mailer', ...);
 
-        $container->setDefinition('app.newsletter_manager', new Definition(
-            NewsletterManager::class,
-            array(
-                new Reference(
-                    'app.mailer',
-                    ContainerInterface::NULL_ON_INVALID_REFERENCE
-                )
-            )
-        ));
+        $container->register('app.newsletter_manager', NewsletterManager::class)
+            ->addArgument(new Reference(
+                'app.mailer',
+                ContainerInterface::NULL_ON_INVALID_REFERENCE
+            ));
 
 .. note::
 
diff --git a/service_container/request.rst b/service_container/request.rst
index 4867ed5bbd8..aa954b4f1e6 100644
--- a/service_container/request.rst
+++ b/service_container/request.rst
@@ -66,14 +66,12 @@ Now, just inject the ``request_stack``, which behaves like any normal service:
     .. code-block:: php
 
         // src/AppBundle/Resources/config/services.php
-        use Symfony\Component\DependencyInjection\Definition;
+        use AppBundle\Newsletter\NewsletterManager;
         use Symfony\Component\DependencyInjection\Reference;
 
         // ...
-        $container->setDefinition('newsletter_manager', new Definition(
-            'AppBundle\Newsletter\NewsletterManager',
-            array(new Reference('request_stack'))
-        ));
+        $container->register('newsletter_manager', NewsletterManager::class)
+            ->addArgument(new Reference('request_stack'));
 
 .. tip::
 
diff --git a/service_container/tags.rst b/service_container/tags.rst
index 7e1e560f1a0..417a6ae6047 100644
--- a/service_container/tags.rst
+++ b/service_container/tags.rst
@@ -168,15 +168,12 @@ For example, you may add the following transports as services:
 
     .. code-block:: php
 
-        use Symfony\Component\DependencyInjection\Definition;
+        $container->register('app.smtp_transport', '\Swift_SmtpTransport')
+            ->addArgument('%mailer_host%')
+            ->addTag('app.mail_transport');
 
-        $definitionSmtp = new Definition('\Swift_SmtpTransport', array('%mailer_host%'));
-        $definitionSmtp->addTag('app.mail_transport');
-        $container->setDefinition('app.smtp_transport', $definitionSmtp);
-
-        $definitionSendmail = new Definition('\Swift_SendmailTransport');
-        $definitionSendmail->addTag('app.mail_transport');
-        $container->setDefinition('app.sendmail_transport', $definitionSendmail);
+        $container->register('app.sendmail_transport', '\Swift_SendmailTransport')
+            ->addTag('app.mail_transport');
 
 Notice that each service was given a tag named ``app.mail_transport``. This is
 the custom tag that you'll use in your compiler pass. The compiler pass is what
@@ -321,15 +318,12 @@ To answer this, change the service declaration:
 
     .. code-block:: php
 
-        use Symfony\Component\DependencyInjection\Definition;
-
-        $definitionSmtp = new Definition('\Swift_SmtpTransport', array('%mailer_host%'));
-        $definitionSmtp->addTag('app.mail_transport', array('alias' => 'foo'));
-        $container->setDefinition('app.smtp_transport', $definitionSmtp);
+        $container->register('app.smtp_transport', '\Swift_SmtpTransport')
+            ->addArgument('%mailer_host%')
+            ->addTag('app.mail_transport', array('alias' => 'foo'));
 
-        $definitionSendmail = new Definition('\Swift_SendmailTransport');
-        $definitionSendmail->addTag('app.mail_transport', array('alias' => 'bar'));
-        $container->setDefinition('app.sendmail_transport', $definitionSendmail);
+        $container->register('app.sendmail_transport', '\Swift_SendmailTransport')
+            ->addTag('app.mail_transport', array('alias' => 'bar'));
 
 .. tip::
 
diff --git a/service_container/third_party.rst b/service_container/third_party.rst
index 3c29a02fa96..636c16f1861 100644
--- a/service_container/third_party.rst
+++ b/service_container/third_party.rst
@@ -85,13 +85,11 @@ Configuring the service container is easy:
         // app/config/services.php
         use AppBundle\Newsletter\NewsletterManager;
 
-        $container->setDefinition('app.newsletter_manager', new Definition(
-            NewsletterManager::class,
-            array(
+        $container->register('app.newsletter_manager', NewsletterManager::class)
+            ->setArguments(array(
                 new Reference('mailer'),
                 new Reference('templating'),
-            )
-        ));
+            ));
 
 The ``app.newsletter_manager`` service now has access to the core ``mailer``
 and ``templating`` services. This is a common way to create services specific
diff --git a/session/locale_sticky_session.rst b/session/locale_sticky_session.rst
index ab734276aaa..7d5101c95ac 100644
--- a/session/locale_sticky_session.rst
+++ b/session/locale_sticky_session.rst
@@ -83,15 +83,10 @@ Then register the listener:
     .. code-block:: php
 
         use AppBundle\EventListener\LocaleListener;
-        use Symfony\Component\DependencyInjection\Definition;
 
-        $container
-            ->setDefinition('app.locale_listener', new Definition(
-                LocaleListener::class,
-                array('%kernel.default_locale%')
-            ))
-            ->addTag('kernel.event_subscriber')
-        ;
+        $container->register('app.locale_listener', LocaleListener::class)
+            ->addArgument('%kernel.default_locale%')
+            ->addTag('kernel.event_subscriber');
 
 That's it! Now celebrate by changing the user's locale and seeing that it's
 sticky throughout the request. Remember, to get the user's locale, always
diff --git a/templating/twig_extension.rst b/templating/twig_extension.rst
index f352da02cb6..043d6f2c40f 100644
--- a/templating/twig_extension.rst
+++ b/templating/twig_extension.rst
@@ -95,7 +95,6 @@ Now you must let the Service Container know about your newly created Twig Extens
 
         // app/config/services.php
         use AppBundle\Twig\AppExtension;
-        use Symfony\Component\DependencyInjection\Definition;
 
         $container
             ->register('app.twig_extension', AppExtension::class)