diff --git a/docs/infrastructure_and_maintenance/cache/http_cache/reverse_proxy.md b/docs/infrastructure_and_maintenance/cache/http_cache/reverse_proxy.md
index c672765d53..3a2e6fc471 100644
--- a/docs/infrastructure_and_maintenance/cache/http_cache/reverse_proxy.md
+++ b/docs/infrastructure_and_maintenance/cache/http_cache/reverse_proxy.md
@@ -20,7 +20,7 @@ To use the Symfony reverse proxy, you must change your `public/index.php` front
 
  require_once dirname(__DIR__).'/vendor/autoload_runtime.php';
 
- return function (array $context) {
+ return static function (array $context) {
 -    return new Kernel($context['APP_ENV'], (bool) $context['APP_DEBUG']);
 +    return new AppCache(new Kernel($context['APP_ENV'], (bool) $context['APP_DEBUG']));
  };