diff --git a/composer.json b/composer.json
index 4f2acc0..9cf5325 100644
--- a/composer.json
+++ b/composer.json
@@ -28,7 +28,7 @@
         "guzzlehttp/psr7": "^1.7 || ^2.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "^8.0 || ^9.0",
+        "phpunit/phpunit": "^8.0 || ^9.0 || ^12.0",
         "friendsofphp/php-cs-fixer": "^3.5"
     },
     "autoload": {