diff --git a/CacheWarmer/SerializerCacheWarmer.php b/CacheWarmer/SerializerCacheWarmer.php
index 398972da..bc9e9e2b 100644
--- a/CacheWarmer/SerializerCacheWarmer.php
+++ b/CacheWarmer/SerializerCacheWarmer.php
@@ -11,7 +11,7 @@
  * Run purify() with various contents to have the caches built here, and not
  * on first use, as the owning user may be different then, causing problems
  * with file ownership when deleting the cached files later.
- * 
+ *
  * @author Henrik Bjornskov <henrik@bjrnskov.dk>
  */
 class SerializerCacheWarmer implements CacheWarmerInterface
@@ -33,7 +33,7 @@ public function __construct(array $paths, HTMLPurifier $htmlPurifier)
     }
 
     /**
-     * @see Symfony\Component\HttpKernel\CacheWarmer\WarmableInterface::warmUp()
+     * @see \Symfony\Component\HttpKernel\CacheWarmer\WarmableInterface::warmUp()
      */
     public function warmUp($cacheDir)
     {
@@ -53,7 +53,7 @@ public function warmUp($cacheDir)
     }
 
     /**
-     * @see Symfony\Component\HttpKernel\CacheWarmer\CacheWarmerInterface::isOptional()
+     * @see \Symfony\Component\HttpKernel\CacheWarmer\CacheWarmerInterface::isOptional()
      */
     public function isOptional()
     {
diff --git a/DependencyInjection/ExerciseHTMLPurifierExtension.php b/DependencyInjection/ExerciseHTMLPurifierExtension.php
index ab208509..b3ca00c8 100644
--- a/DependencyInjection/ExerciseHTMLPurifierExtension.php
+++ b/DependencyInjection/ExerciseHTMLPurifierExtension.php
@@ -37,42 +37,27 @@ public function load(array $configs, ContainerBuilder $container)
 
         foreach ($configs as $name => $config) {
             $configDefinition = new Definition('%exercise_html_purifier.config.class%');
-			
-            // Handle Symfony >= 2.7
-            if (method_exists($configDefinition, 'setFactory')) {
-                if ('default' === $name) {
-                    $configDefinition
-                        ->setFactory(array('%exercise_html_purifier.config.class%', 'create'))
-                        ->addArgument($config);
-                } else {
-                    $configDefinition
-                        ->setFactory(array('%exercise_html_purifier.config.class%', 'inherit'))
-                        ->addArgument(new Reference('exercise_html_purifier.config.default'))
-                        ->addMethodCall('loadArray', array($config));
-                }
-            }
-            // Handle Symfony < 2.7
-            else {
-                $configDefinition->setFactoryClass('%exercise_html_purifier.config.class%');
-
-                if ('default' === $name) {
-                    $configDefinition
-                        ->setFactoryMethod('create')
-                        ->addArgument($config);
-                } else {
-                    $configDefinition
-                        ->setFactoryMethod('inherit')
-                        ->addArgument(new Reference('exercise_html_purifier.config.default'))
-                        ->addMethodCall('loadArray', array($config));
-                }
+
+            if ('default' === $name) {
+                $configDefinition
+                    ->setFactory(array('%exercise_html_purifier.config.class%', 'create'))
+                    ->addArgument($config);
+            } else {
+                $configDefinition
+                    ->setFactory(array('%exercise_html_purifier.config.class%', 'inherit'))
+                    ->addArgument(new Reference('exercise_html_purifier.config.default'))
+                    ->addMethodCall('loadArray', array($config));
             }
 
             $configId = 'exercise_html_purifier.config.' . $name;
             $container->setDefinition($configId, $configDefinition);
 
+            $purifierDefinition = new Definition('%exercise_html_purifier.class%', array(new Reference($configId)));
+            $purifierDefinition->setPublic(true);
+
             $container->setDefinition(
                 'exercise_html_purifier.' . $name,
-                new Definition('%exercise_html_purifier.class%', array(new Reference($configId)))
+                $purifierDefinition
             );
 
             if (isset($config['Cache.SerializerPath'])) {
diff --git a/Tests/DependencyInjection/ExerciseHTMLPurifierExtensionTest.php b/Tests/DependencyInjection/ExerciseHTMLPurifierExtensionTest.php
index 71faeb08..26769e00 100644
--- a/Tests/DependencyInjection/ExerciseHTMLPurifierExtensionTest.php
+++ b/Tests/DependencyInjection/ExerciseHTMLPurifierExtensionTest.php
@@ -8,12 +8,12 @@
 class ExerciseHTMLPurifierExtensionTest extends \PHPUnit_Framework_TestCase
 {
     /**
-     * @var Symfony\Component\DependencyInjection\ContainerBuilder
+     * @var \Symfony\Component\DependencyInjection\ContainerBuilder
      */
     private $container;
 
     /**
-     * @var Exercise\HTMLPurifierBundle\DependencyInjection\ExerciseHTMLPurifierExtension
+     * @var \Exercise\HTMLPurifierBundle\DependencyInjection\ExerciseHTMLPurifierExtension
      */
     private $extension;
 
@@ -74,9 +74,6 @@ public function testShouldNotDeepMergeOptions()
 
     public function testShouldLoadCustomConfiguration()
     {
-        $container = new ContainerBuilder();
-        $extension = new ExerciseHTMLPurifierExtension();
-
         $config = array(
             'default' => array(
                 'AutoFormat.AutoParagraph'          => true,
@@ -108,9 +105,6 @@ public function testShouldLoadCustomConfiguration()
 
     public function testShouldResolveServices()
     {
-        $container = new ContainerBuilder;
-        $extension = new ExerciseHTMLPurifierExtension();
-
         $config = array(
             'simple' => array(
                 'AutoFormat.Custom' => array('@service_container'),
diff --git a/Twig/HTMLPurifierExtension.php b/Twig/HTMLPurifierExtension.php
index db404bd1..84ed0f08 100644
--- a/Twig/HTMLPurifierExtension.php
+++ b/Twig/HTMLPurifierExtension.php
@@ -13,7 +13,7 @@ class HTMLPurifierExtension extends \Twig_Extension
     /**
      * Constructor.
      *
-     * @param \HTMLPurifier $purifier
+     * @param ContainerInterface $container
      */
     public function __construct(ContainerInterface $container)
     {
diff --git a/composer.json b/composer.json
index 09e37bf6..be3216e9 100644
--- a/composer.json
+++ b/composer.json
@@ -1,7 +1,7 @@
 {
     "name": "exercise/htmlpurifier-bundle",
     "type": "symfony-bundle",
-    "description": "HTMLPurifier integration for your Symfony2 project",
+    "description": "HTMLPurifier integration for your Symfony project",
     "keywords": ["htmlpurifier"],
     "homepage": "https://github.com/Exercise/HTMLPurifierBundle",
     "license": "MIT",
@@ -10,11 +10,11 @@
     ],
     "require": {
         "php": ">=5.3.2",
-        "symfony/framework-bundle": "~2.0|~3.0",
+        "symfony/framework-bundle": "^2.7 || ^3.0 || ^4.0",
         "ezyang/htmlpurifier": "~4.0"
     },
     "require-dev": {
-        "symfony/form": "~2.0",
+        "symfony/form": "^2.7 || ^3.0 || ^4.0",
         "twig/twig": "~1.3|~2.0"
     },
     "extra": {