diff --git a/composer.json b/composer.json
index c8d5c91..bed6037 100644
--- a/composer.json
+++ b/composer.json
@@ -14,7 +14,7 @@
     },
     "require": {
         "php": "^7.0",
-        "symfony/options-resolver": "^3.2"
+        "symfony/options-resolver": "^3.2|~4.0"
     },
     "require-dev": {
         "phpunit/phpunit": "^5.7"