diff --git a/lib/AppInfo/Application.php b/lib/AppInfo/Application.php
index 89e6d64bc..8abd29a50 100644
--- a/lib/AppInfo/Application.php
+++ b/lib/AppInfo/Application.php
@@ -1,4 +1,6 @@
 <?php
+
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/AuthorizedAdminSettingMiddleware.php b/lib/AuthorizedAdminSettingMiddleware.php
index abff09e6a..6abcb7527 100644
--- a/lib/AuthorizedAdminSettingMiddleware.php
+++ b/lib/AuthorizedAdminSettingMiddleware.php
@@ -1,5 +1,6 @@
 <?php
 
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2022 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Controller/DelegationController.php b/lib/Controller/DelegationController.php
index 2bead302e..c1fad6e76 100644
--- a/lib/Controller/DelegationController.php
+++ b/lib/Controller/DelegationController.php
@@ -1,5 +1,6 @@
 <?php
 
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2021 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Controller/FolderController.php b/lib/Controller/FolderController.php
index 669ceadc2..9f7fe0aa7 100644
--- a/lib/Controller/FolderController.php
+++ b/lib/Controller/FolderController.php
@@ -1,5 +1,6 @@
 <?php
 
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Folder/FolderManager.php b/lib/Folder/FolderManager.php
index 019184de6..9639ff580 100644
--- a/lib/Folder/FolderManager.php
+++ b/lib/Folder/FolderManager.php
@@ -1,4 +1,6 @@
 <?php
+
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Migration/Version102020Date20180806161449.php b/lib/Migration/Version102020Date20180806161449.php
index 9aef4de68..fd31d6950 100644
--- a/lib/Migration/Version102020Date20180806161449.php
+++ b/lib/Migration/Version102020Date20180806161449.php
@@ -1,5 +1,6 @@
 <?php
 
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Migration/Version103000Date20180806161724.php b/lib/Migration/Version103000Date20180806161724.php
index c7f0e8d23..500cce8e8 100644
--- a/lib/Migration/Version103000Date20180806161724.php
+++ b/lib/Migration/Version103000Date20180806161724.php
@@ -1,5 +1,6 @@
 <?php
 
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Mount/GroupFolderStorage.php b/lib/Mount/GroupFolderStorage.php
index 36c0df4bb..e8007541c 100644
--- a/lib/Mount/GroupFolderStorage.php
+++ b/lib/Mount/GroupFolderStorage.php
@@ -1,4 +1,6 @@
 <?php
+
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Mount/GroupMountPoint.php b/lib/Mount/GroupMountPoint.php
index ee02ba8b8..fcb184b16 100644
--- a/lib/Mount/GroupMountPoint.php
+++ b/lib/Mount/GroupMountPoint.php
@@ -1,4 +1,6 @@
 <?php
+
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Mount/MountProvider.php b/lib/Mount/MountProvider.php
index dff103d83..8c3d6b2b9 100644
--- a/lib/Mount/MountProvider.php
+++ b/lib/Mount/MountProvider.php
@@ -1,4 +1,6 @@
 <?php
+
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Service/ApplicationService.php b/lib/Service/ApplicationService.php
index d552a138c..f7dca20e2 100644
--- a/lib/Service/ApplicationService.php
+++ b/lib/Service/ApplicationService.php
@@ -1,5 +1,6 @@
 <?php
 
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2022 Baptiste Fotia <baptiste.fotia@arawa.fr> for Arawa (https://arawa.fr)
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Service/DelegationService.php b/lib/Service/DelegationService.php
index ac3d6fca4..4b8e25537 100644
--- a/lib/Service/DelegationService.php
+++ b/lib/Service/DelegationService.php
@@ -1,5 +1,6 @@
 <?php
 
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2022 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Service/FoldersFilter.php b/lib/Service/FoldersFilter.php
index dfcf50a78..ffe69ea0f 100644
--- a/lib/Service/FoldersFilter.php
+++ b/lib/Service/FoldersFilter.php
@@ -1,5 +1,6 @@
 <?php
 
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2022 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Settings/Admin.php b/lib/Settings/Admin.php
index 5b80c1438..78e229e95 100644
--- a/lib/Settings/Admin.php
+++ b/lib/Settings/Admin.php
@@ -1,4 +1,6 @@
 <?php
+
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Settings/Section.php b/lib/Settings/Section.php
index 126a6aa66..8a1361197 100644
--- a/lib/Settings/Section.php
+++ b/lib/Settings/Section.php
@@ -1,4 +1,6 @@
 <?php
+
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Trash/GroupTrashItem.php b/lib/Trash/GroupTrashItem.php
index 7371f0487..64c5d6ddf 100644
--- a/lib/Trash/GroupTrashItem.php
+++ b/lib/Trash/GroupTrashItem.php
@@ -1,4 +1,6 @@
 <?php
+
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Trash/TrashBackend.php b/lib/Trash/TrashBackend.php
index 961ca6046..fabaa4025 100644
--- a/lib/Trash/TrashBackend.php
+++ b/lib/Trash/TrashBackend.php
@@ -1,4 +1,6 @@
 <?php
+
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/Trash/TrashManager.php b/lib/Trash/TrashManager.php
index b44834387..ffc8d7e83 100644
--- a/lib/Trash/TrashManager.php
+++ b/lib/Trash/TrashManager.php
@@ -1,4 +1,6 @@
 <?php
+
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/tests/ACL/ACLScannerTest.php b/tests/ACL/ACLScannerTest.php
index 9c5bb17d3..e52349ad8 100644
--- a/tests/ACL/ACLScannerTest.php
+++ b/tests/ACL/ACLScannerTest.php
@@ -1,5 +1,6 @@
 <?php
 
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/tests/Folder/FolderManagerTest.php b/tests/Folder/FolderManagerTest.php
index 19b2afd4c..5bc511f3c 100644
--- a/tests/Folder/FolderManagerTest.php
+++ b/tests/Folder/FolderManagerTest.php
@@ -1,4 +1,6 @@
 <?php
+
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index cdc08c490..7bfebc8bd 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -1,5 +1,6 @@
 <?php
 
+declare (strict_types=1);
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later