diff --git a/Classes/Command/TestCommand.php b/Classes/Command/TestCommand.php
index dc52a91..e41ef5a 100644
--- a/Classes/Command/TestCommand.php
+++ b/Classes/Command/TestCommand.php
@@ -36,7 +36,7 @@ protected function configure()
     /**
      * @inheritdoc
      */
-    protected function execute(InputInterface $input, OutputInterface $output)
+    protected function execute(InputInterface $input, OutputInterface $output): int
     {
         $io = new SymfonyStyle($input, $output);