diff --git a/app/Services/CheckinCsvImporter.php b/app/Services/CheckinCsvImporter.php
index e03ae4d..f33785c 100644
--- a/app/Services/CheckinCsvImporter.php
+++ b/app/Services/CheckinCsvImporter.php
@@ -1,4 +1,5 @@
 <?php
+declare(strict_types=1);
 
 namespace App\Services;
 
diff --git a/tests/Unit/Services/CheckinCsvImporterTest.php b/tests/Unit/Services/CheckinCsvImporterTest.php
index e3e9be3..9ba29aa 100644
--- a/tests/Unit/Services/CheckinCsvImporterTest.php
+++ b/tests/Unit/Services/CheckinCsvImporterTest.php
@@ -1,4 +1,5 @@
 <?php
+declare(strict_types=1);
 
 namespace Tests\Unit\Services;