diff --git a/lib/Controller/SessionController.php b/lib/Controller/SessionController.php
index 784596b2b..d0cf5485a 100644
--- a/lib/Controller/SessionController.php
+++ b/lib/Controller/SessionController.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022, chandi Langecker (git@chandi.it)
  *
diff --git a/lib/Db/Session.php b/lib/Db/Session.php
index 8533777cb..ae0151ddb 100644
--- a/lib/Db/Session.php
+++ b/lib/Db/Session.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022, chandi Langecker (git@chandi.it)
  *
diff --git a/lib/Db/SessionMapper.php b/lib/Db/SessionMapper.php
index 7a31138ed..84d552474 100644
--- a/lib/Db/SessionMapper.php
+++ b/lib/Db/SessionMapper.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022, chandi Langecker (git@chandi.it)
  *
diff --git a/lib/Event/SessionClosedEvent.php b/lib/Event/SessionClosedEvent.php
index f5b164d5d..3364ea28a 100644
--- a/lib/Event/SessionClosedEvent.php
+++ b/lib/Event/SessionClosedEvent.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022, chandi Langecker (git@chandi.it)
  *
@@ -29,7 +32,7 @@ class SessionClosedEvent extends Event {
 	private $boardId;
 	private $userId;
 	
-	public function __construct($boardId, $userId) {
+	public function __construct(int $boardId, string $userId) {
 		parent::__construct();
 
 		$this->boardId = $boardId;
diff --git a/lib/Event/SessionCreatedEvent.php b/lib/Event/SessionCreatedEvent.php
index 8182f1e74..8c2e3c11c 100644
--- a/lib/Event/SessionCreatedEvent.php
+++ b/lib/Event/SessionCreatedEvent.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022, chandi Langecker (git@chandi.it)
  *
@@ -30,7 +33,7 @@ class SessionCreatedEvent extends Event {
 	private $boardId;
 	private $userId;
 	
-	public function __construct($boardId, $userId) {
+	public function __construct(int $boardId, string $userId) {
 		parent::__construct();
 
 		$this->boardId = $boardId;
diff --git a/lib/NotifyPushEvents.php b/lib/NotifyPushEvents.php
index 3fed8d11d..f12daa582 100644
--- a/lib/NotifyPushEvents.php
+++ b/lib/NotifyPushEvents.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022, chandi Langecker (git@chandi.it)
  *
diff --git a/lib/Service/SessionService.php b/lib/Service/SessionService.php
index bd8ab34cc..3ef033ef4 100644
--- a/lib/Service/SessionService.php
+++ b/lib/Service/SessionService.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2022, chandi Langecker (git@chandi.it)
  *