diff --git a/src/Generators/Google.php b/src/Generators/Google.php
index bd0ab1d..7f716da 100644
--- a/src/Generators/Google.php
+++ b/src/Generators/Google.php
@@ -1,4 +1,4 @@
-<?php
+<?php declare(strict_types=1);
 
 namespace Spatie\CalendarLinks\Generators;