diff --git a/composer.json b/composer.json
index f53f67c..10e4a35 100644
--- a/composer.json
+++ b/composer.json
@@ -25,7 +25,7 @@
         "wyrihaximus/ticking-promise": "^3.1"
     },
     "require-dev": {
-        "react-parallel/pool-tests": "^4.0.0",
+        "react-parallel/pool-tests": "^4.0.0 || ^5.0.0",
         "wyrihaximus/async-test-utilities": "^7.2"
     },
     "autoload": {