diff --git a/composer.json b/composer.json
index 91e6031..6465459 100644
--- a/composer.json
+++ b/composer.json
@@ -18,7 +18,7 @@
     }
   },
   "require-dev": {
-    "phpunit/phpunit": "~9.6.0",
+    "phpunit/phpunit": "~13.1.5",
     "squizlabs/php_codesniffer": "~3.13.1"
   }
 }