diff --git a/Tests/Resources/app/AppKernel.php b/Tests/Resources/app/AppKernel.php
index f45dcfa0..5ed35f89 100644
--- a/Tests/Resources/app/AppKernel.php
+++ b/Tests/Resources/app/AppKernel.php
@@ -2,6 +2,7 @@
 
 use Symfony\Bundle\FrameworkBundle\Kernel\MicroKernelTrait;
 use Symfony\Component\Config\Loader\LoaderInterface;
+use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\HttpKernel\Kernel;
@@ -86,4 +87,43 @@ public function indexAction()
     {
         return new Response();
     }
+
+    protected function build(ContainerBuilder $container)
+    {
+        $container->addCompilerPass(new PublicServicesForFunctionalTestsPass());
+    }
+}
+
+class PublicServicesForFunctionalTestsPass implements CompilerPassInterface
+{
+    public function process(ContainerBuilder $container)
+    {
+        $services = [
+            'httplug.strategy',
+            'httplug.auto_discovery.auto_discovered_client',
+            'httplug.auto_discovery.auto_discovered_async',
+            'httplug.message_factory.default',
+            'httplug.stream_factory.default',
+            'httplug.uri_factory.default',
+            'httplug.async_client.default',
+            'httplug.client.default',
+            'app.http.plugin.custom',
+            'httplug.client.acme',
+        ];
+        foreach ($services as $service) {
+            if ($container->hasDefinition($service)) {
+                $container->getDefinition($service)->setPublic(true);
+            }
+
+        }
+
+        $aliases = [
+            'httplug.client',
+        ];
+        foreach ($aliases as $alias) {
+            if ($container->hasAlias($alias)) {
+                $container->getAlias($alias)->setPublic(true);
+            }
+        }
+    }
 }
diff --git a/composer.json b/composer.json
index aa4f37aa..41661bae 100644
--- a/composer.json
+++ b/composer.json
@@ -23,14 +23,14 @@
         "php-http/cache-plugin": "^1.4",
         "php-http/logger-plugin": "^1.0",
         "php-http/stopwatch-plugin": "^1.0",
-        "symfony/options-resolver": "^2.8 || ^3.0",
-        "symfony/event-dispatcher": "^2.8 || ^3.0",
-        "symfony/framework-bundle": "^2.8 || ^3.0",
+        "symfony/options-resolver": "^2.8 || ^3.0 || ^4.0",
+        "symfony/event-dispatcher": "^2.8 || ^3.0 || ^4.0",
+        "symfony/framework-bundle": "^2.8 || ^3.0 || ^4.0",
         "php-http/message": "^1.4",
         "php-http/discovery": "^1.0",
         "twig/twig": "^1.18 || ^2.0",
-        "symfony/asset": "^2.8 || ^3.0",
-        "symfony/dependency-injection": "^2.8.3 || ^3.0.3"
+        "symfony/asset": "^2.8 || ^3.0 || ^4.0",
+        "symfony/dependency-injection": "^2.8.3 || ^3.0.3 || ^4.0"
     },
     "require-dev": {
         "phpunit/php-token-stream": "^1.1.8",
@@ -41,13 +41,13 @@
         "php-http/buzz-adapter": "^0.3",
         "php-http/mock-client": "^1.0",
         "symfony/phpunit-bridge": "^3.3 || ^4.0",
-        "symfony/twig-bundle": "^2.8 || ^3.0",
-        "symfony/twig-bridge": "^2.8 || ^3.0",
-        "symfony/web-profiler-bundle": "^2.8 || ^3.0",
-        "symfony/finder": "^2.7 || ^3.0",
-        "symfony/cache": "^3.1",
-        "symfony/browser-kit": "^2.8 || ^3.0",
-        "symfony/dom-crawler": "^2.8 || ^3.0",
+        "symfony/twig-bundle": "^2.8 || ^3.0 || ^4.0",
+        "symfony/twig-bridge": "^2.8 || ^3.0 || ^4.0",
+        "symfony/web-profiler-bundle": "^2.8 || ^3.0 || ^4.0",
+        "symfony/finder": "^2.7 || ^3.0 || ^4.0",
+        "symfony/cache": "^3.1 || ^4.0",
+        "symfony/browser-kit": "^2.8 || ^3.0 || ^4.0",
+        "symfony/dom-crawler": "^2.8 || ^3.0 || ^4.0",
         "polishsymfonycommunity/symfony-mocker-container": "^1.0",
         "matthiasnoback/symfony-dependency-injection-test": "^1.1 || ^2.0",
         "nyholm/nsa": "^1.1"