diff --git a/composer.json b/composer.json
index 70672d0e..4ea3c9ce 100644
--- a/composer.json
+++ b/composer.json
@@ -15,7 +15,7 @@
         "psr/log": "^1.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "^4.3",
+        "phpunit/phpunit": "^4.3||^5.0",
         "monolog/monolog": "^1.11",
         "squizlabs/php_codesniffer": "^2.5"
     },