diff --git a/Classes/CampaignsFactory.php b/Classes/CampaignsFactory.php
index 86d3726..1d616c2 100644
--- a/Classes/CampaignsFactory.php
+++ b/Classes/CampaignsFactory.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace SkillDisplay\Typo3Extension;
 
 /*
diff --git a/Tests/Unit/CampaignsFactoryTest.php b/Tests/Unit/CampaignsFactoryTest.php
index f166ad4..7af8940 100644
--- a/Tests/Unit/CampaignsFactoryTest.php
+++ b/Tests/Unit/CampaignsFactoryTest.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace SkillDisplay\Typo3Extension\Tests\Unit;
 
 /*
diff --git a/Tests/Unit/TcaEnhancerTest.php b/Tests/Unit/TcaEnhancerTest.php
index f42941f..f27b8ac 100644
--- a/Tests/Unit/TcaEnhancerTest.php
+++ b/Tests/Unit/TcaEnhancerTest.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace SkillDisplay\Typo3Extension\Tests\Unit;
 
 /*