diff --git a/composer.json b/composer.json
index 8731b72..1ef72f1 100644
--- a/composer.json
+++ b/composer.json
@@ -47,6 +47,9 @@
         "symfony/phpunit-bridge": "^6.0"
     },
     "config": {
-        "sort-packages": true
+        "sort-packages": true,
+        "allow-plugins": {
+            "phpstan/extension-installer": true
+        }
     }
 }