diff --git a/composer.json b/composer.json
index e88fcd4..519403d 100644
--- a/composer.json
+++ b/composer.json
@@ -16,7 +16,7 @@
     },
     "require-dev": {
       "phpunit/phpunit": "*",
-      "phpunit/php-code-coverage": "*"
+      "phpunit/php-code-coverage": "^4"
     },
     "autoload": {
         "psr-0": { "Fenom\\": "src/" },