diff --git a/src/N98/Magento/Command/Developer/Console/Shell.php b/src/N98/Magento/Command/Developer/Console/Shell.php
index 7280997d4..9a4385f30 100644
--- a/src/N98/Magento/Command/Developer/Console/Shell.php
+++ b/src/N98/Magento/Command/Developer/Console/Shell.php
@@ -38,7 +38,7 @@ class Shell extends PsyShell
      * @param OutputInterface|null $output
      * @return int
      */
-    public function run(InputInterface $input = null, OutputInterface $output = null)
+    public function run(InputInterface $input = null, OutputInterface $output = null): int
     {
         $this->registerHelpersFromMainApplication();