diff --git a/composer.json b/composer.json
index 277a92c..b6110cd 100644
--- a/composer.json
+++ b/composer.json
@@ -20,7 +20,7 @@
         "bowphp/policier": "^3.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "^8",
+        "phpunit/phpunit": "^9",
         "monolog/monolog": "^1.22",
         "squizlabs/php_codesniffer": "3.*"
     },