diff --git a/modules/helfi_tpr_config/src/Entity/Unit.php b/modules/helfi_tpr_config/src/Entity/Unit.php
index 35e267e0a..af2add89e 100644
--- a/modules/helfi_tpr_config/src/Entity/Unit.php
+++ b/modules/helfi_tpr_config/src/Entity/Unit.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Drupal\helfi_tpr_config\Entity;
 
 use Drupal\helfi_tpr\Entity\Unit as BaseUnit;
diff --git a/src/Token/OGImageBuilderInterface.php b/src/Token/OGImageBuilderInterface.php
index cb84b8ae3..546ab89bb 100644
--- a/src/Token/OGImageBuilderInterface.php
+++ b/src/Token/OGImageBuilderInterface.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Drupal\helfi_platform_config\Token;
 
 use Drupal\Core\Entity\EntityInterface;
diff --git a/src/Token/OGImageManager.php b/src/Token/OGImageManager.php
index 5e4a3cbcd..f0bf5142f 100644
--- a/src/Token/OGImageManager.php
+++ b/src/Token/OGImageManager.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Drupal\helfi_platform_config\Token;
 
 use Drupal\Component\Utility\UrlHelper;