diff --git a/composer.json b/composer.json
index 9432bc6..818141a 100644
--- a/composer.json
+++ b/composer.json
@@ -16,7 +16,7 @@
         "php": "~7.3.0||~7.4.0||~8.1.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "~6.5",
+        "phpunit/phpunit": "~6.5||~9.5.0",
         "roave/security-advisories": "dev-latest"
     },
     "autoload": {