diff --git a/composer.json b/composer.json
index 1b54a22..9f08cf3 100644
--- a/composer.json
+++ b/composer.json
@@ -45,7 +45,8 @@
   "require-dev": {
     "phpunit/phpunit": "^10.5.44|^11.5.6",
     "phpstan/phpstan": "^2.1.2",
-    "friendsofphp/php-cs-fixer": "^v3.68.5"
+    "friendsofphp/php-cs-fixer": "^v3.91.3",
+    "symfony/polyfill-iconv": "^1.33"
   },
   "autoload": {
     "psr-4": {