diff --git a/composer.json b/composer.json
index c4ad15b..6eabeb4 100644
--- a/composer.json
+++ b/composer.json
@@ -16,7 +16,7 @@
         "react/filesystem": "^0.2@dev"
     },
     "require-dev": {
-        "wyrihaximus/async-test-utilities": "^8.0.4"
+        "wyrihaximus/async-test-utilities": "^9.4.2"
     },
     "minimum-stability": "dev",
     "prefer-stable": true,