diff --git a/.travis.yml b/.travis.yml
index a2769bfbc..f954b0a8c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -21,6 +21,7 @@ matrix:
   include:
     - env: SYMFONY_VERSION=3.3.x-dev
     - env: SYMFONY_VERSION=3.4.x-dev
+    - env: SYMFONY_VERSION=4.0.x-dev
   allow_failures:
     - php: nightly
   fast_finish: true
diff --git a/composer.json b/composer.json
index 655519dc6..667ca4f94 100644
--- a/composer.json
+++ b/composer.json
@@ -20,14 +20,14 @@
     "require": {
         "php": "~7.1",
         "imagine/Imagine": "^0.6.3,<0.7",
-        "symfony/asset": "~3.0",
-        "symfony/filesystem": "~3.0",
-        "symfony/finder": "~3.0",
-        "symfony/framework-bundle": "~3.0",
-        "symfony/options-resolver": "~3.0",
-        "symfony/process": "~3.0",
-        "symfony/templating": "~3.0",
-        "symfony/translation": "~3.0"
+        "symfony/asset": "~3.0|^4.0",
+        "symfony/filesystem": "~3.0|^4.0",
+        "symfony/finder": "~3.0|^4.0",
+        "symfony/framework-bundle": "~3.0|^4.0",
+        "symfony/options-resolver": "~3.0|^4.0",
+        "symfony/process": "~3.0|^4.0",
+        "symfony/templating": "~3.0|^4.0",
+        "symfony/translation": "~3.0|^4.0"
     },
     "require-dev": {
         "ext-gd": "*",
@@ -35,20 +35,19 @@
         "aws/aws-sdk-php": "~2.4",
         "doctrine/cache": "~1.1",
         "doctrine/orm": "~2.3",
-        "enqueue/enqueue-bundle": "^0.7",
-        "friendsofphp/php-cs-fixer": "~1.0",
+        "enqueue/enqueue-bundle": "^0.7|^0.8",
+        "friendsofphp/php-cs-fixer": "~1.0|~2.0",
         "league/flysystem": "~1.0",
         "phpunit/phpunit": "~5.0",
         "psr/log": "~1.0",
         "satooshi/php-coveralls": "~1.0",
-        "sllh/php-cs-fixer-styleci-bridge": "~2.1",
-        "symfony/browser-kit": "~3.0",
-        "symfony/console": "~3.0",
-        "symfony/dependency-injection": "~3.0",
-        "symfony/form": "~3.0",
-        "symfony/phpunit-bridge": "~3.0",
-        "symfony/validator": "~3.0",
-        "symfony/yaml": "~3.0",
+        "symfony/browser-kit": "~3.0|^4.0",
+        "symfony/console": "~3.0|^4.0",
+        "symfony/dependency-injection": "~3.0|^4.0",
+        "symfony/form": "~3.0|^4.0",
+        "symfony/phpunit-bridge": "~3.0|^4.0",
+        "symfony/validator": "~3.0|^4.0",
+        "symfony/yaml": "~3.0|^4.0",
         "twig/twig": "~1.12|~2.0"
     },
     "suggest": {