diff --git a/src/Symfony/Bridge/Twig/CHANGELOG.md b/src/Symfony/Bridge/Twig/CHANGELOG.md
index dee3db5a37..04c7dfb43d 100644
--- a/src/Symfony/Bridge/Twig/CHANGELOG.md
+++ b/src/Symfony/Bridge/Twig/CHANGELOG.md
@@ -28,7 +28,7 @@ CHANGELOG
    // ...
    $rendererEngine = new TwigRendererEngine(array('form_div_layout.html.twig'), $twig);
    // require Twig 1.30+
-   $twig->addRuntimeLoader(new \Twig_FactoryRuntimeLoader(array(
+   $twig->addRuntimeLoader(new \Twig\RuntimeLoader\FactoryRuntimeLoader(array(
        TwigRenderer::class => function () use ($rendererEngine, $csrfTokenManager) {
            return new TwigRenderer($rendererEngine, $csrfTokenManager);
        },
diff --git a/src/Symfony/Bridge/Twig/Extension/FormExtension.php b/src/Symfony/Bridge/Twig/Extension/FormExtension.php
index 2cff5996f6..362879e43a 100644
--- a/src/Symfony/Bridge/Twig/Extension/FormExtension.php
+++ b/src/Symfony/Bridge/Twig/Extension/FormExtension.php
@@ -38,7 +38,7 @@ class FormExtension extends AbstractExtension implements InitRuntimeInterface
     public function __construct($renderer = null)
     {
         if ($renderer instanceof TwigRendererInterface) {
-            @trigger_error(sprintf('Passing a Twig Form Renderer to the "%s" constructor is deprecated since version 3.2 and won\'t be possible in 4.0. Pass the Twig_Environment to the TwigRendererEngine constructor instead.', static::class), E_USER_DEPRECATED);
+            @trigger_error(sprintf('Passing a Twig Form Renderer to the "%s" constructor is deprecated since version 3.2 and won\'t be possible in 4.0. Pass the Twig\Environment to the TwigRendererEngine constructor instead.', static::class), E_USER_DEPRECATED);
         } elseif (null !== $renderer && !(is_array($renderer) && isset($renderer[0], $renderer[1]) && $renderer[0] instanceof ContainerInterface)) {
             throw new \InvalidArgumentException(sprintf('Passing any arguments the constructor of %s is reserved for internal use.', __CLASS__));
         }
diff --git a/src/Symfony/Bridge/Twig/Extension/WorkflowExtension.php b/src/Symfony/Bridge/Twig/Extension/WorkflowExtension.php
index 2e5459fa07..e93008c84a 100644
--- a/src/Symfony/Bridge/Twig/Extension/WorkflowExtension.php
+++ b/src/Symfony/Bridge/Twig/Extension/WorkflowExtension.php
@@ -13,13 +13,15 @@ namespace Symfony\Bridge\Twig\Extension;
 
 use Symfony\Component\Workflow\Registry;
 use Symfony\Component\Workflow\Transition;
+use Twig\Extension\AbstractExtension;
+use Twig\TwigFunction;
 
 /**
  * WorkflowExtension.
  *
  * @author Grégoire Pineau <lyrixx@lyrixx.info>
  */
-class WorkflowExtension extends \Twig_Extension
+class WorkflowExtension extends AbstractExtension
 {
     private $workflowRegistry;
 
@@ -31,8 +33,8 @@ class WorkflowExtension extends \Twig_Extension
     public function getFunctions()
     {
         return array(
-            new \Twig_SimpleFunction('workflow_can', array($this, 'canTransition')),
-            new \Twig_SimpleFunction('workflow_transitions', array($this, 'getEnabledTransitions')),
+            new TwigFunction('workflow_can', array($this, 'canTransition')),
+            new TwigFunction('workflow_transitions', array($this, 'getEnabledTransitions')),
         );
     }
 
diff --git a/src/Symfony/Bridge/Twig/Form/TwigRendererEngine.php b/src/Symfony/Bridge/Twig/Form/TwigRendererEngine.php
index 8e4790ed8d..3805c7416f 100644
--- a/src/Symfony/Bridge/Twig/Form/TwigRendererEngine.php
+++ b/src/Symfony/Bridge/Twig/Form/TwigRendererEngine.php
@@ -31,7 +31,7 @@ class TwigRendererEngine extends AbstractRendererEngine implements TwigRendererE
      */
     private $template;
 
-    public function __construct(array $defaultThemes = array(), \Twig_Environment $environment = null)
+    public function __construct(array $defaultThemes = array(), Environment $environment = null)
     {
         if (null === $environment) {
             @trigger_error(sprintf('Not passing a Twig Environment as the second argument for "%s" constructor is deprecated since version 3.2 and won\'t be possible in 4.0.', static::class), E_USER_DEPRECATED);
diff --git a/src/Symfony/Bridge/Twig/Tests/Extension/DumpExtensionTest.php b/src/Symfony/Bridge/Twig/Tests/Extension/DumpExtensionTest.php
index f71d81648b..ce80418c83 100644
--- a/src/Symfony/Bridge/Twig/Tests/Extension/DumpExtensionTest.php
+++ b/src/Symfony/Bridge/Twig/Tests/Extension/DumpExtensionTest.php
@@ -123,7 +123,7 @@ class DumpExtensionTest extends TestCase
             '</pre><script>Sfdump("%s")</script>'
         );
         $extension = new DumpExtension(new VarCloner(), $dumper);
-        $twig = new \Twig_Environment($this->getMockBuilder('Twig_LoaderInterface')->getMock(), array(
+        $twig = new Environment($this->getMockBuilder('Twig\Loader\LoaderInterface')->getMock(), array(
             'debug' => true,
             'cache' => false,
             'optimizations' => 0,
diff --git a/src/Symfony/Bridge/Twig/Tests/Extension/HttpKernelExtensionTest.php b/src/Symfony/Bridge/Twig/Tests/Extension/HttpKernelExtensionTest.php
index ee48ce058f..9f19847eb8 100644
--- a/src/Symfony/Bridge/Twig/Tests/Extension/HttpKernelExtensionTest.php
+++ b/src/Symfony/Bridge/Twig/Tests/Extension/HttpKernelExtensionTest.php
@@ -81,7 +81,7 @@ class HttpKernelExtensionTest extends TestCase
         $twig = new Environment($loader, array('debug' => true, 'cache' => false));
         $twig->addExtension(new HttpKernelExtension());
 
-        $loader = $this->getMockBuilder('Twig\Loader\RuntimeLoaderInterface')->getMock();
+        $loader = $this->getMockBuilder('Twig\RuntimeLoader\RuntimeLoaderInterface')->getMock();
         $loader->expects($this->any())->method('load')->will($this->returnValueMap(array(
             array('Symfony\Bridge\Twig\Extension\HttpKernelRuntime', new HttpKernelRuntime($renderer)),
         )));
diff --git a/src/Symfony/Bridge/Twig/Tests/Extension/RuntimeLoaderProvider.php b/src/Symfony/Bridge/Twig/Tests/Extension/RuntimeLoaderProvider.php
index a6c397ffd4..90db2c5d6b 100644
--- a/src/Symfony/Bridge/Twig/Tests/Extension/RuntimeLoaderProvider.php
+++ b/src/Symfony/Bridge/Twig/Tests/Extension/RuntimeLoaderProvider.php
@@ -12,12 +12,13 @@
 namespace Symfony\Bridge\Twig\Tests\Extension;
 
 use Symfony\Bridge\Twig\Form\TwigRenderer;
+use Twig\Environment;
 
 trait RuntimeLoaderProvider
 {
-    protected function registerTwigRuntimeLoader(\Twig_Environment $environment, TwigRenderer $renderer)
+    protected function registerTwigRuntimeLoader(Environment $environment, TwigRenderer $renderer)
     {
-        $loader = $this->getMockBuilder('Twig_RuntimeLoaderInterface')->getMock();
+        $loader = $this->getMockBuilder('Twig\RuntimeLoader\RuntimeLoaderInterface')->getMock();
         $loader->expects($this->any())->method('load')->will($this->returnValueMap(array(
             array('Symfony\Bridge\Twig\Form\TwigRenderer', $renderer),
         )));
diff --git a/src/Symfony/Bundle/TwigBundle/ContainerAwareRuntimeLoader.php b/src/Symfony/Bundle/TwigBundle/ContainerAwareRuntimeLoader.php
index 780454aed9..94815467c0 100644
--- a/src/Symfony/Bundle/TwigBundle/ContainerAwareRuntimeLoader.php
+++ b/src/Symfony/Bundle/TwigBundle/ContainerAwareRuntimeLoader.php
@@ -13,13 +13,14 @@ namespace Symfony\Bundle\TwigBundle;
 
 use Psr\Log\LoggerInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
+use Twig\RuntimeLoader\RuntimeLoaderInterface;
 
 /**
  * Loads Twig extension runtimes via the service container.
  *
  * @author Fabien Potencier <fabien@symfony.com>
  */
-class ContainerAwareRuntimeLoader implements \Twig_RuntimeLoaderInterface
+class ContainerAwareRuntimeLoader implements RuntimeLoaderInterface
 {
     private $container;
     private $mapping;