diff --git a/apps/admin_audit/lib/IAuditLogger.php b/apps/admin_audit/lib/IAuditLogger.php
index f17afa6852e5b..635c063753fdc 100644
--- a/apps/admin_audit/lib/IAuditLogger.php
+++ b/apps/admin_audit/lib/IAuditLogger.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2022 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/comments/appinfo/routes.php b/apps/comments/appinfo/routes.php
index 903f1b2168c99..3c44eacda9447 100644
--- a/apps/comments/appinfo/routes.php
+++ b/apps/comments/appinfo/routes.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/comments/lib/Activity/Filter.php b/apps/comments/lib/Activity/Filter.php
index 8dcafd872d749..58777c3b03c2f 100644
--- a/apps/comments/lib/Activity/Filter.php
+++ b/apps/comments/lib/Activity/Filter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/comments/lib/Activity/Setting.php b/apps/comments/lib/Activity/Setting.php
index 2f332d99b43c7..2a44c0889f58b 100644
--- a/apps/comments/lib/Activity/Setting.php
+++ b/apps/comments/lib/Activity/Setting.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/comments/lib/AppInfo/Application.php b/apps/comments/lib/AppInfo/Application.php
index db4a2ce614c11..9d1132f5ce5d2 100644
--- a/apps/comments/lib/AppInfo/Application.php
+++ b/apps/comments/lib/AppInfo/Application.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/appinfo/routes.php b/apps/dav/appinfo/routes.php
index dba7bcbbdf07f..705ccf18943a0 100644
--- a/apps/dav/appinfo/routes.php
+++ b/apps/dav/appinfo/routes.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Activity/Filter/Calendar.php b/apps/dav/lib/CalDAV/Activity/Filter/Calendar.php
index 78579ee84b7f1..064cbbf39c1d3 100644
--- a/apps/dav/lib/CalDAV/Activity/Filter/Calendar.php
+++ b/apps/dav/lib/CalDAV/Activity/Filter/Calendar.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Activity/Filter/Todo.php b/apps/dav/lib/CalDAV/Activity/Filter/Todo.php
index b001f90c28dde..3c2dd935203b0 100644
--- a/apps/dav/lib/CalDAV/Activity/Filter/Todo.php
+++ b/apps/dav/lib/CalDAV/Activity/Filter/Todo.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Activity/Setting/Calendar.php b/apps/dav/lib/CalDAV/Activity/Setting/Calendar.php
index 0ad86a919bc5c..8e777048027f4 100644
--- a/apps/dav/lib/CalDAV/Activity/Setting/Calendar.php
+++ b/apps/dav/lib/CalDAV/Activity/Setting/Calendar.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Activity/Setting/Event.php b/apps/dav/lib/CalDAV/Activity/Setting/Event.php
index ea9476d6f08bd..c10d37d890264 100644
--- a/apps/dav/lib/CalDAV/Activity/Setting/Event.php
+++ b/apps/dav/lib/CalDAV/Activity/Setting/Event.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Activity/Setting/Todo.php b/apps/dav/lib/CalDAV/Activity/Setting/Todo.php
index ed8377b0ffae9..39bcd440112ff 100644
--- a/apps/dav/lib/CalDAV/Activity/Setting/Todo.php
+++ b/apps/dav/lib/CalDAV/Activity/Setting/Todo.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Integration/ExternalCalendar.php b/apps/dav/lib/CalDAV/Integration/ExternalCalendar.php
index acf81638679e9..edacdd42ea78f 100644
--- a/apps/dav/lib/CalDAV/Integration/ExternalCalendar.php
+++ b/apps/dav/lib/CalDAV/Integration/ExternalCalendar.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2020 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Integration/ICalendarProvider.php b/apps/dav/lib/CalDAV/Integration/ICalendarProvider.php
index 40a8860dcb45b..d913b91f1f0ef 100644
--- a/apps/dav/lib/CalDAV/Integration/ICalendarProvider.php
+++ b/apps/dav/lib/CalDAV/Integration/ICalendarProvider.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2020 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Outbox.php b/apps/dav/lib/CalDAV/Outbox.php
index 608114d80934d..a2339790bed08 100644
--- a/apps/dav/lib/CalDAV/Outbox.php
+++ b/apps/dav/lib/CalDAV/Outbox.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Principal/User.php b/apps/dav/lib/CalDAV/Principal/User.php
index 047d83827ed7c..c7b84e6ce4c7f 100644
--- a/apps/dav/lib/CalDAV/Principal/User.php
+++ b/apps/dav/lib/CalDAV/Principal/User.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/PublicCalendarObject.php b/apps/dav/lib/CalDAV/PublicCalendarObject.php
index 2ab40b9434745..a05b09b0deb5f 100644
--- a/apps/dav/lib/CalDAV/PublicCalendarObject.php
+++ b/apps/dav/lib/CalDAV/PublicCalendarObject.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php b/apps/dav/lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php
index c70d93daf5229..adeb8939c887d 100644
--- a/apps/dav/lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php
+++ b/apps/dav/lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php b/apps/dav/lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php
index 5704b23ae142e..1cc8770739fae 100644
--- a/apps/dav/lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php
+++ b/apps/dav/lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Search/Xml/Filter/CompFilter.php b/apps/dav/lib/CalDAV/Search/Xml/Filter/CompFilter.php
index 21a4fff1caf80..a95470a8b47df 100644
--- a/apps/dav/lib/CalDAV/Search/Xml/Filter/CompFilter.php
+++ b/apps/dav/lib/CalDAV/Search/Xml/Filter/CompFilter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Search/Xml/Filter/LimitFilter.php b/apps/dav/lib/CalDAV/Search/Xml/Filter/LimitFilter.php
index a98b325397b0d..7c56a50cdd9f2 100644
--- a/apps/dav/lib/CalDAV/Search/Xml/Filter/LimitFilter.php
+++ b/apps/dav/lib/CalDAV/Search/Xml/Filter/LimitFilter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Search/Xml/Filter/OffsetFilter.php b/apps/dav/lib/CalDAV/Search/Xml/Filter/OffsetFilter.php
index ef438aa025848..8e06b722c0392 100644
--- a/apps/dav/lib/CalDAV/Search/Xml/Filter/OffsetFilter.php
+++ b/apps/dav/lib/CalDAV/Search/Xml/Filter/OffsetFilter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Search/Xml/Filter/ParamFilter.php b/apps/dav/lib/CalDAV/Search/Xml/Filter/ParamFilter.php
index 0c31f32348ac2..057e337d0d315 100644
--- a/apps/dav/lib/CalDAV/Search/Xml/Filter/ParamFilter.php
+++ b/apps/dav/lib/CalDAV/Search/Xml/Filter/ParamFilter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Search/Xml/Filter/PropFilter.php b/apps/dav/lib/CalDAV/Search/Xml/Filter/PropFilter.php
index 251120e35ccfe..3ff265e80f5ad 100644
--- a/apps/dav/lib/CalDAV/Search/Xml/Filter/PropFilter.php
+++ b/apps/dav/lib/CalDAV/Search/Xml/Filter/PropFilter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/CalDAV/Search/Xml/Filter/SearchTermFilter.php b/apps/dav/lib/CalDAV/Search/Xml/Filter/SearchTermFilter.php
index 6d6bf95849674..9445158f3dbdc 100644
--- a/apps/dav/lib/CalDAV/Search/Xml/Filter/SearchTermFilter.php
+++ b/apps/dav/lib/CalDAV/Search/Xml/Filter/SearchTermFilter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/Capabilities.php b/apps/dav/lib/Capabilities.php
index f9bad25bf3176..2c87112673fa9 100644
--- a/apps/dav/lib/Capabilities.php
+++ b/apps/dav/lib/Capabilities.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 ownCloud GmbH
  * SPDX-License-Identifier: AGPL-3.0-only
diff --git a/apps/dav/lib/CardDAV/Activity/Filter.php b/apps/dav/lib/CardDAV/Activity/Filter.php
index 8b221a29ff010..7724fb59c163d 100644
--- a/apps/dav/lib/CardDAV/Activity/Filter.php
+++ b/apps/dav/lib/CardDAV/Activity/Filter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2021 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/Command/SendEventReminders.php b/apps/dav/lib/Command/SendEventReminders.php
index 89bb5ce8c205b..6fff7d62f1f21 100644
--- a/apps/dav/lib/Command/SendEventReminders.php
+++ b/apps/dav/lib/Command/SendEventReminders.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/Command/SyncSystemAddressBook.php b/apps/dav/lib/Command/SyncSystemAddressBook.php
index 54edba01e0593..b8b7f53a905da 100644
--- a/apps/dav/lib/Command/SyncSystemAddressBook.php
+++ b/apps/dav/lib/Command/SyncSystemAddressBook.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/dav/lib/Connector/Sabre/Exception/BadGateway.php b/apps/dav/lib/Connector/Sabre/Exception/BadGateway.php
index 1e1e4aaed041b..65d8d30719b40 100644
--- a/apps/dav/lib/Connector/Sabre/Exception/BadGateway.php
+++ b/apps/dav/lib/Connector/Sabre/Exception/BadGateway.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2021 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-only
diff --git a/apps/dav/lib/Connector/Sabre/Exception/EntityTooLarge.php b/apps/dav/lib/Connector/Sabre/Exception/EntityTooLarge.php
index 60b3b06ea012a..eb892f91cdad5 100644
--- a/apps/dav/lib/Connector/Sabre/Exception/EntityTooLarge.php
+++ b/apps/dav/lib/Connector/Sabre/Exception/EntityTooLarge.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/dav/lib/Connector/Sabre/Exception/UnsupportedMediaType.php b/apps/dav/lib/Connector/Sabre/Exception/UnsupportedMediaType.php
index c5fbfa3a16c9b..84420dd75d5f8 100644
--- a/apps/dav/lib/Connector/Sabre/Exception/UnsupportedMediaType.php
+++ b/apps/dav/lib/Connector/Sabre/Exception/UnsupportedMediaType.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/dav/lib/Connector/Sabre/ExceptionLoggerPlugin.php b/apps/dav/lib/Connector/Sabre/ExceptionLoggerPlugin.php
index 686386dbfefa8..7aab4f576d746 100644
--- a/apps/dav/lib/Connector/Sabre/ExceptionLoggerPlugin.php
+++ b/apps/dav/lib/Connector/Sabre/ExceptionLoggerPlugin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/dav/lib/Connector/Sabre/MtimeSanitizer.php b/apps/dav/lib/Connector/Sabre/MtimeSanitizer.php
index 48d210ebb1bfa..7b26a76c2aafa 100644
--- a/apps/dav/lib/Connector/Sabre/MtimeSanitizer.php
+++ b/apps/dav/lib/Connector/Sabre/MtimeSanitizer.php
@@ -1,10 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2021 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-
 namespace OCA\DAV\Connector\Sabre;
 
 class MtimeSanitizer {
diff --git a/apps/dav/lib/DAV/Sharing/IShareable.php b/apps/dav/lib/DAV/Sharing/IShareable.php
index d83079f697545..019559548ad57 100644
--- a/apps/dav/lib/DAV/Sharing/IShareable.php
+++ b/apps/dav/lib/DAV/Sharing/IShareable.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/dav/lib/Files/Sharing/PublicLinkCheckPlugin.php b/apps/dav/lib/Files/Sharing/PublicLinkCheckPlugin.php
index 38a45b3fc37e4..c3b269fb9ed43 100644
--- a/apps/dav/lib/Files/Sharing/PublicLinkCheckPlugin.php
+++ b/apps/dav/lib/Files/Sharing/PublicLinkCheckPlugin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/dav/lib/Migration/BuildCalendarSearchIndex.php b/apps/dav/lib/Migration/BuildCalendarSearchIndex.php
index d8f906f22eecf..0ff7355b7249f 100644
--- a/apps/dav/lib/Migration/BuildCalendarSearchIndex.php
+++ b/apps/dav/lib/Migration/BuildCalendarSearchIndex.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/Migration/BuildSocialSearchIndex.php b/apps/dav/lib/Migration/BuildSocialSearchIndex.php
index 26a3c21079c11..e6163bd2346b0 100644
--- a/apps/dav/lib/Migration/BuildSocialSearchIndex.php
+++ b/apps/dav/lib/Migration/BuildSocialSearchIndex.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/Migration/RegenerateBirthdayCalendars.php b/apps/dav/lib/Migration/RegenerateBirthdayCalendars.php
index ef8e9002e9dac..ec9f3bce45d65 100644
--- a/apps/dav/lib/Migration/RegenerateBirthdayCalendars.php
+++ b/apps/dav/lib/Migration/RegenerateBirthdayCalendars.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/Migration/Version1004Date20170926103422.php b/apps/dav/lib/Migration/Version1004Date20170926103422.php
index ec56e035006b0..333bdd197fffc 100644
--- a/apps/dav/lib/Migration/Version1004Date20170926103422.php
+++ b/apps/dav/lib/Migration/Version1004Date20170926103422.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/Provisioning/Apple/AppleProvisioningNode.php b/apps/dav/lib/Provisioning/Apple/AppleProvisioningNode.php
index bb098a0f107b4..845c87cfce1cd 100644
--- a/apps/dav/lib/Provisioning/Apple/AppleProvisioningNode.php
+++ b/apps/dav/lib/Provisioning/Apple/AppleProvisioningNode.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/Provisioning/Apple/AppleProvisioningPlugin.php b/apps/dav/lib/Provisioning/Apple/AppleProvisioningPlugin.php
index 31621cbc97c85..28100c5c9c7b0 100644
--- a/apps/dav/lib/Provisioning/Apple/AppleProvisioningPlugin.php
+++ b/apps/dav/lib/Provisioning/Apple/AppleProvisioningPlugin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/Settings/CalDAVSettings.php b/apps/dav/lib/Settings/CalDAVSettings.php
index da48ae5db1b31..bffcfef90207c 100644
--- a/apps/dav/lib/Settings/CalDAVSettings.php
+++ b/apps/dav/lib/Settings/CalDAVSettings.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/dav/lib/SystemTag/SystemTagObjectType.php b/apps/dav/lib/SystemTag/SystemTagObjectType.php
index 0d348cd95f4bb..9157da12a9173 100644
--- a/apps/dav/lib/SystemTag/SystemTagObjectType.php
+++ b/apps/dav/lib/SystemTag/SystemTagObjectType.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-only
diff --git a/apps/encryption/lib/Command/DisableMasterKey.php b/apps/encryption/lib/Command/DisableMasterKey.php
index 53902e42ed1ee..409753f39f0c3 100644
--- a/apps/encryption/lib/Command/DisableMasterKey.php
+++ b/apps/encryption/lib/Command/DisableMasterKey.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/encryption/lib/Command/EnableMasterKey.php b/apps/encryption/lib/Command/EnableMasterKey.php
index 96b4eb218a472..1a65530495e35 100644
--- a/apps/encryption/lib/Command/EnableMasterKey.php
+++ b/apps/encryption/lib/Command/EnableMasterKey.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/encryption/lib/Exceptions/MultiKeyDecryptException.php b/apps/encryption/lib/Exceptions/MultiKeyDecryptException.php
index 1246d51190bb9..77cef173f32af 100644
--- a/apps/encryption/lib/Exceptions/MultiKeyDecryptException.php
+++ b/apps/encryption/lib/Exceptions/MultiKeyDecryptException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/encryption/lib/Exceptions/MultiKeyEncryptException.php b/apps/encryption/lib/Exceptions/MultiKeyEncryptException.php
index 60394af45c273..b3eb441d7fcf6 100644
--- a/apps/encryption/lib/Exceptions/MultiKeyEncryptException.php
+++ b/apps/encryption/lib/Exceptions/MultiKeyEncryptException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/encryption/lib/Exceptions/PrivateKeyMissingException.php b/apps/encryption/lib/Exceptions/PrivateKeyMissingException.php
index 15fe8f4e72f68..784ba0b088504 100644
--- a/apps/encryption/lib/Exceptions/PrivateKeyMissingException.php
+++ b/apps/encryption/lib/Exceptions/PrivateKeyMissingException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/encryption/lib/Exceptions/PublicKeyMissingException.php b/apps/encryption/lib/Exceptions/PublicKeyMissingException.php
index 78eeeccf47d1e..41209106fa334 100644
--- a/apps/encryption/lib/Exceptions/PublicKeyMissingException.php
+++ b/apps/encryption/lib/Exceptions/PublicKeyMissingException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/encryption/lib/Settings/Admin.php b/apps/encryption/lib/Settings/Admin.php
index 1ac2ab5ff5eeb..6b6c54c999b86 100644
--- a/apps/encryption/lib/Settings/Admin.php
+++ b/apps/encryption/lib/Settings/Admin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/federatedfilesharing/appinfo/routes.php b/apps/federatedfilesharing/appinfo/routes.php
index a7e135548c758..944509a51c4bc 100644
--- a/apps/federatedfilesharing/appinfo/routes.php
+++ b/apps/federatedfilesharing/appinfo/routes.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/federatedfilesharing/lib/Settings/PersonalSection.php b/apps/federatedfilesharing/lib/Settings/PersonalSection.php
index eea10e39393b5..c56795308cbfc 100644
--- a/apps/federatedfilesharing/lib/Settings/PersonalSection.php
+++ b/apps/federatedfilesharing/lib/Settings/PersonalSection.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/federatedfilesharing/lib/TokenHandler.php b/apps/federatedfilesharing/lib/TokenHandler.php
index 0151d12f5d93c..f3fdaead8cd9e 100644
--- a/apps/federatedfilesharing/lib/TokenHandler.php
+++ b/apps/federatedfilesharing/lib/TokenHandler.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/federation/appinfo/routes.php b/apps/federation/appinfo/routes.php
index 343870614b3b2..3f6c94dcb47a7 100644
--- a/apps/federation/appinfo/routes.php
+++ b/apps/federation/appinfo/routes.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/federation/lib/Command/SyncFederationAddressBooks.php b/apps/federation/lib/Command/SyncFederationAddressBooks.php
index 36cb99473f761..0325d875969dc 100644
--- a/apps/federation/lib/Command/SyncFederationAddressBooks.php
+++ b/apps/federation/lib/Command/SyncFederationAddressBooks.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/federation/lib/Settings/Admin.php b/apps/federation/lib/Settings/Admin.php
index 892d21a626945..202cb51a645c4 100644
--- a/apps/federation/lib/Settings/Admin.php
+++ b/apps/federation/lib/Settings/Admin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /*!
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/federation/lib/SyncJob.php b/apps/federation/lib/SyncJob.php
index b802dfa9308c5..1e09ca2b054b4 100644
--- a/apps/federation/lib/SyncJob.php
+++ b/apps/federation/lib/SyncJob.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files/lib/Activity/Filter/FileChanges.php b/apps/files/lib/Activity/Filter/FileChanges.php
index 0ca8f6792e0fb..b625f5461fe59 100644
--- a/apps/files/lib/Activity/Filter/FileChanges.php
+++ b/apps/files/lib/Activity/Filter/FileChanges.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files/lib/Activity/Settings/FavoriteAction.php b/apps/files/lib/Activity/Settings/FavoriteAction.php
index 73b200341ec97..0da3232c4fb76 100644
--- a/apps/files/lib/Activity/Settings/FavoriteAction.php
+++ b/apps/files/lib/Activity/Settings/FavoriteAction.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files/lib/Activity/Settings/FileChanged.php b/apps/files/lib/Activity/Settings/FileChanged.php
index c33ed5e1eba8e..f5f98dd30d3be 100644
--- a/apps/files/lib/Activity/Settings/FileChanged.php
+++ b/apps/files/lib/Activity/Settings/FileChanged.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files/lib/Activity/Settings/FileFavoriteChanged.php b/apps/files/lib/Activity/Settings/FileFavoriteChanged.php
index 5000902ed3fce..52e0fcaeb769b 100644
--- a/apps/files/lib/Activity/Settings/FileFavoriteChanged.php
+++ b/apps/files/lib/Activity/Settings/FileFavoriteChanged.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files/lib/Capabilities.php b/apps/files/lib/Capabilities.php
index 6b50e5807a5f6..43eb270922ffd 100644
--- a/apps/files/lib/Capabilities.php
+++ b/apps/files/lib/Capabilities.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files/templates/index.php b/apps/files/templates/index.php
index 5281220282a16..7f74508bef272 100644
--- a/apps/files/templates/index.php
+++ b/apps/files/templates/index.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_external/appinfo/routes.php b/apps/files_external/appinfo/routes.php
index 348c6f9d69e55..b6f4144c6f274 100644
--- a/apps/files_external/appinfo/routes.php
+++ b/apps/files_external/appinfo/routes.php
@@ -1,11 +1,12 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-
 return [
 	'resources' => [
 		'global_storages' => ['url' => '/globalstorages'],
diff --git a/apps/files_external/lib/Command/Dependencies.php b/apps/files_external/lib/Command/Dependencies.php
index d2db8a8c9af08..01e60abe5052a 100644
--- a/apps/files_external/lib/Command/Dependencies.php
+++ b/apps/files_external/lib/Command/Dependencies.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-only
diff --git a/apps/files_external/lib/Command/Export.php b/apps/files_external/lib/Command/Export.php
index 59484d0e7888e..ef8b894dafd36 100644
--- a/apps/files_external/lib/Command/Export.php
+++ b/apps/files_external/lib/Command/Export.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Config/IConfigHandler.php b/apps/files_external/lib/Config/IConfigHandler.php
index 9e8283cc58b8c..aa9709db60080 100644
--- a/apps/files_external/lib/Config/IConfigHandler.php
+++ b/apps/files_external/lib/Config/IConfigHandler.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_external/lib/Config/UserPlaceholderHandler.php b/apps/files_external/lib/Config/UserPlaceholderHandler.php
index d158e6923c16a..a6365ca114cec 100644
--- a/apps/files_external/lib/Config/UserPlaceholderHandler.php
+++ b/apps/files_external/lib/Config/UserPlaceholderHandler.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_external/lib/Lib/Auth/AmazonS3/AccessKey.php b/apps/files_external/lib/Lib/Auth/AmazonS3/AccessKey.php
index c86c88a13d735..cd03999f3cb17 100644
--- a/apps/files_external/lib/Lib/Auth/AmazonS3/AccessKey.php
+++ b/apps/files_external/lib/Lib/Auth/AmazonS3/AccessKey.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Auth/AuthMechanism.php b/apps/files_external/lib/Lib/Auth/AuthMechanism.php
index 7b0544100fbb2..71b138bacf25c 100644
--- a/apps/files_external/lib/Lib/Auth/AuthMechanism.php
+++ b/apps/files_external/lib/Lib/Auth/AuthMechanism.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Auth/Builtin.php b/apps/files_external/lib/Lib/Auth/Builtin.php
index 8e12a6daca6e8..1fb16c14dcc28 100644
--- a/apps/files_external/lib/Lib/Auth/Builtin.php
+++ b/apps/files_external/lib/Lib/Auth/Builtin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Auth/IUserProvided.php b/apps/files_external/lib/Lib/Auth/IUserProvided.php
index 2350d7f6db454..225c8c84d5fa8 100644
--- a/apps/files_external/lib/Lib/Auth/IUserProvided.php
+++ b/apps/files_external/lib/Lib/Auth/IUserProvided.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-only
diff --git a/apps/files_external/lib/Lib/Auth/NullMechanism.php b/apps/files_external/lib/Lib/Auth/NullMechanism.php
index 8e2e5b656b2f8..00f75822c6574 100644
--- a/apps/files_external/lib/Lib/Auth/NullMechanism.php
+++ b/apps/files_external/lib/Lib/Auth/NullMechanism.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Auth/OpenStack/OpenStackV2.php b/apps/files_external/lib/Lib/Auth/OpenStack/OpenStackV2.php
index 3b1c9f123af59..aa3dc14c42d37 100644
--- a/apps/files_external/lib/Lib/Auth/OpenStack/OpenStackV2.php
+++ b/apps/files_external/lib/Lib/Auth/OpenStack/OpenStackV2.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Auth/OpenStack/Rackspace.php b/apps/files_external/lib/Lib/Auth/OpenStack/Rackspace.php
index b1d1068e586cd..d64f5f8dc5b23 100644
--- a/apps/files_external/lib/Lib/Auth/OpenStack/Rackspace.php
+++ b/apps/files_external/lib/Lib/Auth/OpenStack/Rackspace.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Auth/Password/Password.php b/apps/files_external/lib/Lib/Auth/Password/Password.php
index d4291148e3e39..e3299e9366962 100644
--- a/apps/files_external/lib/Lib/Auth/Password/Password.php
+++ b/apps/files_external/lib/Lib/Auth/Password/Password.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Auth/Password/SessionCredentials.php b/apps/files_external/lib/Lib/Auth/Password/SessionCredentials.php
index 8f16107377182..71d277bd72dff 100644
--- a/apps/files_external/lib/Lib/Auth/Password/SessionCredentials.php
+++ b/apps/files_external/lib/Lib/Auth/Password/SessionCredentials.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Auth/SMB/KerberosApacheAuth.php b/apps/files_external/lib/Lib/Auth/SMB/KerberosApacheAuth.php
index 2667111029483..3eeec85ca130e 100644
--- a/apps/files_external/lib/Lib/Auth/SMB/KerberosApacheAuth.php
+++ b/apps/files_external/lib/Lib/Auth/SMB/KerberosApacheAuth.php
@@ -1,10 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace OCA\Files_External\Lib\Auth\SMB;
 
 use OCA\Files_External\Lib\Auth\AuthMechanism;
diff --git a/apps/files_external/lib/Lib/Auth/SMB/KerberosAuth.php b/apps/files_external/lib/Lib/Auth/SMB/KerberosAuth.php
index 9210209192a65..45b0b5825094d 100644
--- a/apps/files_external/lib/Lib/Auth/SMB/KerberosAuth.php
+++ b/apps/files_external/lib/Lib/Auth/SMB/KerberosAuth.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_external/lib/Lib/Backend/AmazonS3.php b/apps/files_external/lib/Lib/Backend/AmazonS3.php
index 9eb479e03f010..06a1a67d72340 100644
--- a/apps/files_external/lib/Lib/Backend/AmazonS3.php
+++ b/apps/files_external/lib/Lib/Backend/AmazonS3.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Backend/DAV.php b/apps/files_external/lib/Lib/Backend/DAV.php
index dea9e7c5e77e3..7c393393be873 100644
--- a/apps/files_external/lib/Lib/Backend/DAV.php
+++ b/apps/files_external/lib/Lib/Backend/DAV.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Backend/FTP.php b/apps/files_external/lib/Lib/Backend/FTP.php
index 72a8184c9b9b3..ab276b871f89b 100644
--- a/apps/files_external/lib/Lib/Backend/FTP.php
+++ b/apps/files_external/lib/Lib/Backend/FTP.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Backend/Local.php b/apps/files_external/lib/Lib/Backend/Local.php
index 56940b8e83b82..59ab6c3ae6898 100644
--- a/apps/files_external/lib/Lib/Backend/Local.php
+++ b/apps/files_external/lib/Lib/Backend/Local.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Backend/OwnCloud.php b/apps/files_external/lib/Lib/Backend/OwnCloud.php
index 0c0e2c6d300e4..fe2cb990a1fb7 100644
--- a/apps/files_external/lib/Lib/Backend/OwnCloud.php
+++ b/apps/files_external/lib/Lib/Backend/OwnCloud.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Backend/SFTP.php b/apps/files_external/lib/Lib/Backend/SFTP.php
index 1ec0d344dd11f..58258d126c6a5 100644
--- a/apps/files_external/lib/Lib/Backend/SFTP.php
+++ b/apps/files_external/lib/Lib/Backend/SFTP.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Backend/SFTP_Key.php b/apps/files_external/lib/Lib/Backend/SFTP_Key.php
index 278fae3fba73f..49a2b9b941716 100644
--- a/apps/files_external/lib/Lib/Backend/SFTP_Key.php
+++ b/apps/files_external/lib/Lib/Backend/SFTP_Key.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Backend/SMB_OC.php b/apps/files_external/lib/Lib/Backend/SMB_OC.php
index bcb8d0fbf1608..25e1b60254ae1 100644
--- a/apps/files_external/lib/Lib/Backend/SMB_OC.php
+++ b/apps/files_external/lib/Lib/Backend/SMB_OC.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Backend/Swift.php b/apps/files_external/lib/Lib/Backend/Swift.php
index 37527ba3dbb3c..452e7546ec2ca 100644
--- a/apps/files_external/lib/Lib/Backend/Swift.php
+++ b/apps/files_external/lib/Lib/Backend/Swift.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Config/IAuthMechanismProvider.php b/apps/files_external/lib/Lib/Config/IAuthMechanismProvider.php
index 0c2e90a243c60..c34c261ffd7e1 100644
--- a/apps/files_external/lib/Lib/Config/IAuthMechanismProvider.php
+++ b/apps/files_external/lib/Lib/Config/IAuthMechanismProvider.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/Config/IBackendProvider.php b/apps/files_external/lib/Lib/Config/IBackendProvider.php
index 44c460c3138c5..9a88ff84556cc 100644
--- a/apps/files_external/lib/Lib/Config/IBackendProvider.php
+++ b/apps/files_external/lib/Lib/Config/IBackendProvider.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/DefinitionParameter.php b/apps/files_external/lib/Lib/DefinitionParameter.php
index a73dd2df9670b..ce0cadc37fb88 100644
--- a/apps/files_external/lib/Lib/DefinitionParameter.php
+++ b/apps/files_external/lib/Lib/DefinitionParameter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/DependencyTrait.php b/apps/files_external/lib/Lib/DependencyTrait.php
index 644132b82bcf7..b62085dbe45ee 100644
--- a/apps/files_external/lib/Lib/DependencyTrait.php
+++ b/apps/files_external/lib/Lib/DependencyTrait.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/IFrontendDefinition.php b/apps/files_external/lib/Lib/IFrontendDefinition.php
index c8b06a1c30b11..7eb9a509c14ee 100644
--- a/apps/files_external/lib/Lib/IFrontendDefinition.php
+++ b/apps/files_external/lib/Lib/IFrontendDefinition.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2022 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_external/lib/Lib/IIdentifier.php b/apps/files_external/lib/Lib/IIdentifier.php
index 0677409a3cff1..e17b908a0b1bb 100644
--- a/apps/files_external/lib/Lib/IIdentifier.php
+++ b/apps/files_external/lib/Lib/IIdentifier.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2022 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_external/lib/Lib/SessionStorageWrapper.php b/apps/files_external/lib/Lib/SessionStorageWrapper.php
index 8754041b2fa39..ea5d788be8f8c 100644
--- a/apps/files_external/lib/Lib/SessionStorageWrapper.php
+++ b/apps/files_external/lib/Lib/SessionStorageWrapper.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Lib/StorageModifierTrait.php b/apps/files_external/lib/Lib/StorageModifierTrait.php
index 4062ff1635e8f..21ddd6bf82847 100644
--- a/apps/files_external/lib/Lib/StorageModifierTrait.php
+++ b/apps/files_external/lib/Lib/StorageModifierTrait.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/NotFoundException.php b/apps/files_external/lib/NotFoundException.php
index 411a221251302..c4534be6c1923 100644
--- a/apps/files_external/lib/NotFoundException.php
+++ b/apps/files_external/lib/NotFoundException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_external/lib/Service/ImportLegacyStoragesService.php b/apps/files_external/lib/Service/ImportLegacyStoragesService.php
index 7d9840e9f5e56..426561adbfcf7 100644
--- a/apps/files_external/lib/Service/ImportLegacyStoragesService.php
+++ b/apps/files_external/lib/Service/ImportLegacyStoragesService.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-only
diff --git a/apps/files_external/lib/Settings/Personal.php b/apps/files_external/lib/Settings/Personal.php
index af38c6bff580e..569fbd858fd72 100644
--- a/apps/files_external/lib/Settings/Personal.php
+++ b/apps/files_external/lib/Settings/Personal.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_external/lib/Settings/PersonalSection.php b/apps/files_external/lib/Settings/PersonalSection.php
index c6eb1c6b889c4..fce0e99a67c40 100644
--- a/apps/files_external/lib/Settings/PersonalSection.php
+++ b/apps/files_external/lib/Settings/PersonalSection.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_external/lib/Settings/Section.php b/apps/files_external/lib/Settings/Section.php
index cf3b73472d7e5..2fca049d1522b 100644
--- a/apps/files_external/lib/Settings/Section.php
+++ b/apps/files_external/lib/Settings/Section.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_external/tests/config.php b/apps/files_external/tests/config.php
index ec860cf05a43d..286224be7a3d3 100644
--- a/apps/files_external/tests/config.php
+++ b/apps/files_external/tests/config.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2012-2016 ownCloud, Inc.
diff --git a/apps/files_external/tests/sso-setup/apps.config.php b/apps/files_external/tests/sso-setup/apps.config.php
index b3889956a5330..8480a4e390f1f 100644
--- a/apps/files_external/tests/sso-setup/apps.config.php
+++ b/apps/files_external/tests/sso-setup/apps.config.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_sharing/appinfo/routes.php b/apps/files_sharing/appinfo/routes.php
index f9e10ebb1062c..a78a99fa8cca5 100644
--- a/apps/files_sharing/appinfo/routes.php
+++ b/apps/files_sharing/appinfo/routes.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_sharing/lib/Activity/Filter.php b/apps/files_sharing/lib/Activity/Filter.php
index 4f3c4a7c91413..6e1110e6f2958 100644
--- a/apps/files_sharing/lib/Activity/Filter.php
+++ b/apps/files_sharing/lib/Activity/Filter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_sharing/lib/Activity/Settings/PublicLinks.php b/apps/files_sharing/lib/Activity/Settings/PublicLinks.php
index 0d3d00d2a7bf9..3e6d7224a88d3 100644
--- a/apps/files_sharing/lib/Activity/Settings/PublicLinks.php
+++ b/apps/files_sharing/lib/Activity/Settings/PublicLinks.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_sharing/lib/Activity/Settings/PublicLinksUpload.php b/apps/files_sharing/lib/Activity/Settings/PublicLinksUpload.php
index fd55752632d59..1e75cb201024a 100644
--- a/apps/files_sharing/lib/Activity/Settings/PublicLinksUpload.php
+++ b/apps/files_sharing/lib/Activity/Settings/PublicLinksUpload.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_sharing/lib/Activity/Settings/RemoteShare.php b/apps/files_sharing/lib/Activity/Settings/RemoteShare.php
index c04364bef201e..c9666e3d7eaad 100644
--- a/apps/files_sharing/lib/Activity/Settings/RemoteShare.php
+++ b/apps/files_sharing/lib/Activity/Settings/RemoteShare.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_sharing/lib/Activity/Settings/Shared.php b/apps/files_sharing/lib/Activity/Settings/Shared.php
index 3717512eebd1b..60f837efd5c11 100644
--- a/apps/files_sharing/lib/Activity/Settings/Shared.php
+++ b/apps/files_sharing/lib/Activity/Settings/Shared.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_sharing/lib/Exceptions/BrokenPath.php b/apps/files_sharing/lib/Exceptions/BrokenPath.php
index a68a8fc05d496..1bd0c9cc8ab66 100644
--- a/apps/files_sharing/lib/Exceptions/BrokenPath.php
+++ b/apps/files_sharing/lib/Exceptions/BrokenPath.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2020-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_sharing/lib/Exceptions/S2SException.php b/apps/files_sharing/lib/Exceptions/S2SException.php
index 10360820432f7..00c66a55655ef 100644
--- a/apps/files_sharing/lib/Exceptions/S2SException.php
+++ b/apps/files_sharing/lib/Exceptions/S2SException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-only
diff --git a/apps/files_sharing/lib/Exceptions/SharingRightsException.php b/apps/files_sharing/lib/Exceptions/SharingRightsException.php
index 2ffe72c4e6977..e1144bc6a1758 100644
--- a/apps/files_sharing/lib/Exceptions/SharingRightsException.php
+++ b/apps/files_sharing/lib/Exceptions/SharingRightsException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_sharing/lib/External/Watcher.php b/apps/files_sharing/lib/External/Watcher.php
index f3616feabba21..e8c8637905f31 100644
--- a/apps/files_sharing/lib/External/Watcher.php
+++ b/apps/files_sharing/lib/External/Watcher.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_sharing/lib/ISharedStorage.php b/apps/files_sharing/lib/ISharedStorage.php
index 9bd3e4c9476ce..e611f0d918fb4 100644
--- a/apps/files_sharing/lib/ISharedStorage.php
+++ b/apps/files_sharing/lib/ISharedStorage.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_sharing/lib/Middleware/OCSShareAPIMiddleware.php b/apps/files_sharing/lib/Middleware/OCSShareAPIMiddleware.php
index 6671a78efff14..7f458b2b53b2d 100644
--- a/apps/files_sharing/lib/Middleware/OCSShareAPIMiddleware.php
+++ b/apps/files_sharing/lib/Middleware/OCSShareAPIMiddleware.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_sharing/lib/Middleware/ShareInfoMiddleware.php b/apps/files_sharing/lib/Middleware/ShareInfoMiddleware.php
index e96940979bf47..e4ba2c88b1761 100644
--- a/apps/files_sharing/lib/Middleware/ShareInfoMiddleware.php
+++ b/apps/files_sharing/lib/Middleware/ShareInfoMiddleware.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_trashbin/lib/Capabilities.php b/apps/files_trashbin/lib/Capabilities.php
index 53c17a475ffee..2f55017fac8df 100644
--- a/apps/files_trashbin/lib/Capabilities.php
+++ b/apps/files_trashbin/lib/Capabilities.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_trashbin/lib/Events/MoveToTrashEvent.php b/apps/files_trashbin/lib/Events/MoveToTrashEvent.php
index 0d776b606b105..9deba9002017c 100644
--- a/apps/files_trashbin/lib/Events/MoveToTrashEvent.php
+++ b/apps/files_trashbin/lib/Events/MoveToTrashEvent.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_trashbin/lib/Exceptions/CopyRecursiveException.php b/apps/files_trashbin/lib/Exceptions/CopyRecursiveException.php
index 3ea1293e5d79f..cec6c92ce6f2f 100644
--- a/apps/files_trashbin/lib/Exceptions/CopyRecursiveException.php
+++ b/apps/files_trashbin/lib/Exceptions/CopyRecursiveException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-only
diff --git a/apps/files_trashbin/lib/Trash/BackendNotFoundException.php b/apps/files_trashbin/lib/Trash/BackendNotFoundException.php
index 292b6ee293c81..2e275c3b37613 100644
--- a/apps/files_trashbin/lib/Trash/BackendNotFoundException.php
+++ b/apps/files_trashbin/lib/Trash/BackendNotFoundException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_trashbin/lib/Trash/ITrashBackend.php b/apps/files_trashbin/lib/Trash/ITrashBackend.php
index 11b3132bfba49..0e30c5972bda6 100644
--- a/apps/files_trashbin/lib/Trash/ITrashBackend.php
+++ b/apps/files_trashbin/lib/Trash/ITrashBackend.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_trashbin/lib/Trash/ITrashItem.php b/apps/files_trashbin/lib/Trash/ITrashItem.php
index 299cac49a69d9..c439ccee37e09 100644
--- a/apps/files_trashbin/lib/Trash/ITrashItem.php
+++ b/apps/files_trashbin/lib/Trash/ITrashItem.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_trashbin/lib/Trash/ITrashManager.php b/apps/files_trashbin/lib/Trash/ITrashManager.php
index 743ea01358a1d..26877f6697ca6 100644
--- a/apps/files_trashbin/lib/Trash/ITrashManager.php
+++ b/apps/files_trashbin/lib/Trash/ITrashManager.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/files_versions/appinfo/routes.php b/apps/files_versions/appinfo/routes.php
index 22ded5e872357..7eb9c821a2518 100644
--- a/apps/files_versions/appinfo/routes.php
+++ b/apps/files_versions/appinfo/routes.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_versions/lib/Capabilities.php b/apps/files_versions/lib/Capabilities.php
index cb6394f0a36ec..248231c69be7b 100644
--- a/apps/files_versions/lib/Capabilities.php
+++ b/apps/files_versions/lib/Capabilities.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/files_versions/lib/Versions/BackendNotFoundException.php b/apps/files_versions/lib/Versions/BackendNotFoundException.php
index f1fbecb852ae3..abed50a388b78 100644
--- a/apps/files_versions/lib/Versions/BackendNotFoundException.php
+++ b/apps/files_versions/lib/Versions/BackendNotFoundException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/oauth2/appinfo/routes.php b/apps/oauth2/appinfo/routes.php
index b34aff05552ea..eadac04f47f4b 100644
--- a/apps/oauth2/appinfo/routes.php
+++ b/apps/oauth2/appinfo/routes.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/oauth2/lib/Db/AccessToken.php b/apps/oauth2/lib/Db/AccessToken.php
index 34adc4f479782..2027371892588 100644
--- a/apps/oauth2/lib/Db/AccessToken.php
+++ b/apps/oauth2/lib/Db/AccessToken.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/oauth2/lib/Db/Client.php b/apps/oauth2/lib/Db/Client.php
index 8fce0040c96e5..b121951993cd4 100644
--- a/apps/oauth2/lib/Db/Client.php
+++ b/apps/oauth2/lib/Db/Client.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/provisioning_api/appinfo/routes.php b/apps/provisioning_api/appinfo/routes.php
index df4f806fa0896..474a716f85234 100644
--- a/apps/provisioning_api/appinfo/routes.php
+++ b/apps/provisioning_api/appinfo/routes.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/provisioning_api/lib/Middleware/Exceptions/NotSubAdminException.php b/apps/provisioning_api/lib/Middleware/Exceptions/NotSubAdminException.php
index b014d6a14955b..771d29bbafbb3 100644
--- a/apps/provisioning_api/lib/Middleware/Exceptions/NotSubAdminException.php
+++ b/apps/provisioning_api/lib/Middleware/Exceptions/NotSubAdminException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/settings/lib/Activity/GroupSetting.php b/apps/settings/lib/Activity/GroupSetting.php
index 917f4a7ef2653..a97c233e6d918 100644
--- a/apps/settings/lib/Activity/GroupSetting.php
+++ b/apps/settings/lib/Activity/GroupSetting.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/settings/lib/Activity/SecurityFilter.php b/apps/settings/lib/Activity/SecurityFilter.php
index 9a32e82a9848d..283b0862ae69f 100644
--- a/apps/settings/lib/Activity/SecurityFilter.php
+++ b/apps/settings/lib/Activity/SecurityFilter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/settings/lib/Activity/SecuritySetting.php b/apps/settings/lib/Activity/SecuritySetting.php
index 9226b5aea5bf0..5a42db555f283 100644
--- a/apps/settings/lib/Activity/SecuritySetting.php
+++ b/apps/settings/lib/Activity/SecuritySetting.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/settings/lib/Activity/Setting.php b/apps/settings/lib/Activity/Setting.php
index f9c659594d6eb..dcc308e29501c 100644
--- a/apps/settings/lib/Activity/Setting.php
+++ b/apps/settings/lib/Activity/Setting.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/settings/lib/Listener/GroupRemovedListener.php b/apps/settings/lib/Listener/GroupRemovedListener.php
index c1b3f888ea8f4..ae73944660734 100644
--- a/apps/settings/lib/Listener/GroupRemovedListener.php
+++ b/apps/settings/lib/Listener/GroupRemovedListener.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2021 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/settings/lib/Sections/Admin/Delegation.php b/apps/settings/lib/Sections/Admin/Delegation.php
index 0dd3b48c20b66..24bb555eae8c7 100644
--- a/apps/settings/lib/Sections/Admin/Delegation.php
+++ b/apps/settings/lib/Sections/Admin/Delegation.php
@@ -1,10 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2021 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace OCA\Settings\Sections\Admin;
 
 use OCP\IL10N;
diff --git a/apps/settings/lib/Service/ConflictException.php b/apps/settings/lib/Service/ConflictException.php
index eab17d7cf0b12..9dbd5aa299317 100644
--- a/apps/settings/lib/Service/ConflictException.php
+++ b/apps/settings/lib/Service/ConflictException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/settings/lib/Service/NotFoundException.php b/apps/settings/lib/Service/NotFoundException.php
index 3abdcf72cd459..b72779349a967 100644
--- a/apps/settings/lib/Service/NotFoundException.php
+++ b/apps/settings/lib/Service/NotFoundException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2021 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/settings/lib/Service/ServiceException.php b/apps/settings/lib/Service/ServiceException.php
index 79c848779ca1f..a9ef5f8762733 100644
--- a/apps/settings/lib/Service/ServiceException.php
+++ b/apps/settings/lib/Service/ServiceException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2021 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/settings/lib/Settings/Admin/Overview.php b/apps/settings/lib/Settings/Admin/Overview.php
index 67ef51b7d5327..8e35605429fa0 100644
--- a/apps/settings/lib/Settings/Admin/Overview.php
+++ b/apps/settings/lib/Settings/Admin/Overview.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/settings/lib/Settings/Personal/Additional.php b/apps/settings/lib/Settings/Personal/Additional.php
index 58fe08a63b706..52b2a33a05d87 100644
--- a/apps/settings/lib/Settings/Personal/Additional.php
+++ b/apps/settings/lib/Settings/Personal/Additional.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/settings/templates/settings/empty.php b/apps/settings/templates/settings/empty.php
index aab6717b49618..9c48245c98a43 100644
--- a/apps/settings/templates/settings/empty.php
+++ b/apps/settings/templates/settings/empty.php
@@ -1,8 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 // Empty template as Vue will take over the `id="content"` of the base template element
diff --git a/apps/sharebymail/lib/Settings/Admin.php b/apps/sharebymail/lib/Settings/Admin.php
index 48592e74ff670..ff7aff9031248 100644
--- a/apps/sharebymail/lib/Settings/Admin.php
+++ b/apps/sharebymail/lib/Settings/Admin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/systemtags/appinfo/routes.php b/apps/systemtags/appinfo/routes.php
index 53997646cc6c7..82151690fa75b 100644
--- a/apps/systemtags/appinfo/routes.php
+++ b/apps/systemtags/appinfo/routes.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/systemtags/lib/Activity/Setting.php b/apps/systemtags/lib/Activity/Setting.php
index 8f39ef41d26f2..84e5bc0f66a56 100644
--- a/apps/systemtags/lib/Activity/Setting.php
+++ b/apps/systemtags/lib/Activity/Setting.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/systemtags/lib/Settings/Admin.php b/apps/systemtags/lib/Settings/Admin.php
index a59c92cc1e601..27f492e1a22fb 100644
--- a/apps/systemtags/lib/Settings/Admin.php
+++ b/apps/systemtags/lib/Settings/Admin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/testing/appinfo/routes.php b/apps/testing/appinfo/routes.php
index 25b16f420dddd..4feb75b88cd60 100644
--- a/apps/testing/appinfo/routes.php
+++ b/apps/testing/appinfo/routes.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2015-2016 ownCloud, Inc.
diff --git a/apps/testing/clean_apcu_cache.php b/apps/testing/clean_apcu_cache.php
index 26cc000b096e2..2ba01c5990701 100644
--- a/apps/testing/clean_apcu_cache.php
+++ b/apps/testing/clean_apcu_cache.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/testing/clean_opcode_cache.php b/apps/testing/clean_opcode_cache.php
index acfeece7e15bf..7ca7af3ab5123 100644
--- a/apps/testing/clean_opcode_cache.php
+++ b/apps/testing/clean_opcode_cache.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/testing/lib/Provider/FakeTextProcessingProvider.php b/apps/testing/lib/Provider/FakeTextProcessingProvider.php
index d3b16c55c6746..991d0c605c86e 100644
--- a/apps/testing/lib/Provider/FakeTextProcessingProvider.php
+++ b/apps/testing/lib/Provider/FakeTextProcessingProvider.php
@@ -1,10 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace OCA\Testing\Provider;
 
 use OCP\TextProcessing\FreePromptTaskType;
diff --git a/apps/testing/lib/Provider/FakeTextProcessingProviderSync.php b/apps/testing/lib/Provider/FakeTextProcessingProviderSync.php
index ea82219910910..01fc200be525a 100644
--- a/apps/testing/lib/Provider/FakeTextProcessingProviderSync.php
+++ b/apps/testing/lib/Provider/FakeTextProcessingProviderSync.php
@@ -1,10 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace OCA\Testing\Provider;
 
 use OCP\TextProcessing\FreePromptTaskType;
diff --git a/apps/testing/lib/Provider/FakeTranslationProvider.php b/apps/testing/lib/Provider/FakeTranslationProvider.php
index cc2d13db646b7..8315cb0960f31 100644
--- a/apps/testing/lib/Provider/FakeTranslationProvider.php
+++ b/apps/testing/lib/Provider/FakeTranslationProvider.php
@@ -1,10 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace OCA\Testing\Provider;
 
 use OCP\Translation\ITranslationProvider;
diff --git a/apps/theming/appinfo/routes.php b/apps/theming/appinfo/routes.php
index b0aedbbb80379..ee83fa5bc17ea 100644
--- a/apps/theming/appinfo/routes.php
+++ b/apps/theming/appinfo/routes.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/theming/lib/AppInfo/Application.php b/apps/theming/lib/AppInfo/Application.php
index d08a19032653c..c0a69e5189ad0 100644
--- a/apps/theming/lib/AppInfo/Application.php
+++ b/apps/theming/lib/AppInfo/Application.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/theming/lib/Command/UpdateConfig.php b/apps/theming/lib/Command/UpdateConfig.php
index 6236f86644560..d0b72ebbc37f5 100644
--- a/apps/theming/lib/Command/UpdateConfig.php
+++ b/apps/theming/lib/Command/UpdateConfig.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2020 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/theming/lib/Settings/Admin.php b/apps/theming/lib/Settings/Admin.php
index 518afe23189cb..ed1f43612152f 100644
--- a/apps/theming/lib/Settings/Admin.php
+++ b/apps/theming/lib/Settings/Admin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/theming/lib/Settings/AdminSection.php b/apps/theming/lib/Settings/AdminSection.php
index a1ea568d9f21b..007b3e904dee1 100644
--- a/apps/theming/lib/Settings/AdminSection.php
+++ b/apps/theming/lib/Settings/AdminSection.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/theming/lib/Settings/PersonalSection.php b/apps/theming/lib/Settings/PersonalSection.php
index c8078bd15778c..ce636f50764d9 100644
--- a/apps/theming/lib/Settings/PersonalSection.php
+++ b/apps/theming/lib/Settings/PersonalSection.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2018 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/updatenotification/templates/empty.php b/apps/updatenotification/templates/empty.php
index 6e020c591edea..cb4d4403a825c 100644
--- a/apps/updatenotification/templates/empty.php
+++ b/apps/updatenotification/templates/empty.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/user_ldap/lib/BackendUtility.php b/apps/user_ldap/lib/BackendUtility.php
index 88d7311cde0b4..65512fc2cf807 100644
--- a/apps/user_ldap/lib/BackendUtility.php
+++ b/apps/user_ldap/lib/BackendUtility.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/user_ldap/lib/Exceptions/AttributeNotSet.php b/apps/user_ldap/lib/Exceptions/AttributeNotSet.php
index 4d6053eda665b..73465c1daad25 100644
--- a/apps/user_ldap/lib/Exceptions/AttributeNotSet.php
+++ b/apps/user_ldap/lib/Exceptions/AttributeNotSet.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/user_ldap/lib/Exceptions/ConstraintViolationException.php b/apps/user_ldap/lib/Exceptions/ConstraintViolationException.php
index d0d384c31de51..22ce85da354cb 100644
--- a/apps/user_ldap/lib/Exceptions/ConstraintViolationException.php
+++ b/apps/user_ldap/lib/Exceptions/ConstraintViolationException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/user_ldap/lib/Exceptions/NotOnLDAP.php b/apps/user_ldap/lib/Exceptions/NotOnLDAP.php
index cd74e9188297c..4c4301130f231 100644
--- a/apps/user_ldap/lib/Exceptions/NotOnLDAP.php
+++ b/apps/user_ldap/lib/Exceptions/NotOnLDAP.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/user_ldap/lib/IGroupLDAP.php b/apps/user_ldap/lib/IGroupLDAP.php
index 667eb421004d2..e10e4fe10b435 100644
--- a/apps/user_ldap/lib/IGroupLDAP.php
+++ b/apps/user_ldap/lib/IGroupLDAP.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/user_ldap/lib/ILDAPGroupPlugin.php b/apps/user_ldap/lib/ILDAPGroupPlugin.php
index 261b9383dc1e2..bb9a5a6066e89 100644
--- a/apps/user_ldap/lib/ILDAPGroupPlugin.php
+++ b/apps/user_ldap/lib/ILDAPGroupPlugin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/user_ldap/lib/ILDAPUserPlugin.php b/apps/user_ldap/lib/ILDAPUserPlugin.php
index 80437bef45221..1490378410221 100644
--- a/apps/user_ldap/lib/ILDAPUserPlugin.php
+++ b/apps/user_ldap/lib/ILDAPUserPlugin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/user_ldap/lib/ILDAPWrapper.php b/apps/user_ldap/lib/ILDAPWrapper.php
index 793eb2b73dc76..c8b388575eb3d 100644
--- a/apps/user_ldap/lib/ILDAPWrapper.php
+++ b/apps/user_ldap/lib/ILDAPWrapper.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/user_ldap/lib/IUserLDAP.php b/apps/user_ldap/lib/IUserLDAP.php
index 5e8e29c3adf0d..6e730fbe94158 100644
--- a/apps/user_ldap/lib/IUserLDAP.php
+++ b/apps/user_ldap/lib/IUserLDAP.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/user_ldap/lib/LDAPUtility.php b/apps/user_ldap/lib/LDAPUtility.php
index 39b517528e2be..b9cbc70a82dd6 100644
--- a/apps/user_ldap/lib/LDAPUtility.php
+++ b/apps/user_ldap/lib/LDAPUtility.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/user_ldap/lib/Mapping/GroupMapping.php b/apps/user_ldap/lib/Mapping/GroupMapping.php
index d9ae5e749fc7d..bd8ed8d64fd32 100644
--- a/apps/user_ldap/lib/Mapping/GroupMapping.php
+++ b/apps/user_ldap/lib/Mapping/GroupMapping.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/apps/user_ldap/lib/Migration/UUIDFixGroup.php b/apps/user_ldap/lib/Migration/UUIDFixGroup.php
index 3924c91e7ba3e..58e157eccbcec 100644
--- a/apps/user_ldap/lib/Migration/UUIDFixGroup.php
+++ b/apps/user_ldap/lib/Migration/UUIDFixGroup.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/user_ldap/lib/Migration/UUIDFixUser.php b/apps/user_ldap/lib/Migration/UUIDFixUser.php
index 71c3f63809536..9ca028d1f8ac0 100644
--- a/apps/user_ldap/lib/Migration/UUIDFixUser.php
+++ b/apps/user_ldap/lib/Migration/UUIDFixUser.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/user_ldap/lib/Service/BirthdateParserService.php b/apps/user_ldap/lib/Service/BirthdateParserService.php
index 8234161b3d8a2..189b440843d76 100644
--- a/apps/user_ldap/lib/Service/BirthdateParserService.php
+++ b/apps/user_ldap/lib/Service/BirthdateParserService.php
@@ -1,10 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace OCA\User_LDAP\Service;
 
 use DateTimeImmutable;
diff --git a/apps/user_ldap/lib/Settings/Section.php b/apps/user_ldap/lib/Settings/Section.php
index 3b95e25513dd1..8abc77cb328b1 100644
--- a/apps/user_ldap/lib/Settings/Section.php
+++ b/apps/user_ldap/lib/Settings/Section.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/user_ldap/tests/Integration/Bootstrap.php b/apps/user_ldap/tests/Integration/Bootstrap.php
index ef0909d4bea71..5f2f50f95e3d2 100644
--- a/apps/user_ldap/tests/Integration/Bootstrap.php
+++ b/apps/user_ldap/tests/Integration/Bootstrap.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/workflowengine/appinfo/routes.php b/apps/workflowengine/appinfo/routes.php
index 48e5ed2ef4e63..7937c65124c5c 100644
--- a/apps/workflowengine/appinfo/routes.php
+++ b/apps/workflowengine/appinfo/routes.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/apps/workflowengine/lib/Settings/Section.php b/apps/workflowengine/lib/Settings/Section.php
index 99de4479dace5..a1fff9d3c75b9 100644
--- a/apps/workflowengine/lib/Settings/Section.php
+++ b/apps/workflowengine/lib/Settings/Section.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/build/rector.php b/build/rector.php
index bd51f7362cb27..e94616b16a5a3 100644
--- a/build/rector.php
+++ b/build/rector.php
@@ -7,6 +7,8 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
+use Rector\TypeDeclaration\Rector\StmtsAwareInterface\SafeDeclareStrictTypesRector;
+
 $nextcloudDir = dirname(__DIR__);
 
 return (require 'rector-shared.php')
@@ -28,4 +30,7 @@
 		// $nextcloudDir . '/config',
 		// $nextcloudDir . '/themes',
 	])
-	->withTypeCoverageLevel(0);
+	->withTypeCoverageLevel(0)
+	->withRules([
+		SafeDeclareStrictTypesRector::class
+	]);
diff --git a/core/Command/Encryption/Disable.php b/core/Command/Encryption/Disable.php
index 91d4ac82d2328..d6b92a9f236c6 100644
--- a/core/Command/Encryption/Disable.php
+++ b/core/Command/Encryption/Disable.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/core/Command/Encryption/Enable.php b/core/Command/Encryption/Enable.php
index 02045fa1a4ba6..c5f7bc6e0e64f 100644
--- a/core/Command/Encryption/Enable.php
+++ b/core/Command/Encryption/Enable.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/core/Command/Encryption/EncryptAll.php b/core/Command/Encryption/EncryptAll.php
index ff552253db4bd..f6cdb2aa15595 100644
--- a/core/Command/Encryption/EncryptAll.php
+++ b/core/Command/Encryption/EncryptAll.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/core/Command/Encryption/ShowKeyStorageRoot.php b/core/Command/Encryption/ShowKeyStorageRoot.php
index 8cf970762493b..17649a260d01d 100644
--- a/core/Command/Encryption/ShowKeyStorageRoot.php
+++ b/core/Command/Encryption/ShowKeyStorageRoot.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/core/Command/Encryption/Status.php b/core/Command/Encryption/Status.php
index 6e4f7d16d0c0e..7e8d0bd0c01bd 100644
--- a/core/Command/Encryption/Status.php
+++ b/core/Command/Encryption/Status.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/core/Command/Integrity/CheckCore.php b/core/Command/Integrity/CheckCore.php
index 49086e94d2653..1eee2679b7060 100644
--- a/core/Command/Integrity/CheckCore.php
+++ b/core/Command/Integrity/CheckCore.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/core/Command/InterruptedException.php b/core/Command/InterruptedException.php
index 661e66725770b..c71942e0f6eef 100644
--- a/core/Command/InterruptedException.php
+++ b/core/Command/InterruptedException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2017 ownCloud, Inc.
diff --git a/core/Command/Maintenance/Mode.php b/core/Command/Maintenance/Mode.php
index 853e843f57b78..19a123980222d 100644
--- a/core/Command/Maintenance/Mode.php
+++ b/core/Command/Maintenance/Mode.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/core/Command/Maintenance/UpdateHtaccess.php b/core/Command/Maintenance/UpdateHtaccess.php
index eeff3bf8c62de..b4a99ddba3461 100644
--- a/core/Command/Maintenance/UpdateHtaccess.php
+++ b/core/Command/Maintenance/UpdateHtaccess.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/core/Command/Maintenance/UpdateTheme.php b/core/Command/Maintenance/UpdateTheme.php
index 3fbcb546cca09..d4c85ec020dc4 100644
--- a/core/Command/Maintenance/UpdateTheme.php
+++ b/core/Command/Maintenance/UpdateTheme.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/core/Command/Status.php b/core/Command/Status.php
index a00d4a94658fd..b76da40ba20fa 100644
--- a/core/Command/Status.php
+++ b/core/Command/Status.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/core/Migrations/Version13000Date20170926101637.php b/core/Migrations/Version13000Date20170926101637.php
index aca772de31320..61bb690be08ac 100644
--- a/core/Migrations/Version13000Date20170926101637.php
+++ b/core/Migrations/Version13000Date20170926101637.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/core/templates/print_exception.php b/core/templates/print_exception.php
index bb66d5abce31f..2ff528f1fd8a1 100644
--- a/core/templates/print_exception.php
+++ b/core/templates/print_exception.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 use OCP\IL10N;
 
 /**
diff --git a/core/templates/print_xml_exception.php b/core/templates/print_xml_exception.php
index f103e13545f34..fa6ba5a746d21 100644
--- a/core/templates/print_xml_exception.php
+++ b/core/templates/print_xml_exception.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 use OCP\IL10N;
 
 /**
diff --git a/lib/private/App/AppStore/Bundles/EducationBundle.php b/lib/private/App/AppStore/Bundles/EducationBundle.php
index 23681ec7416a9..47a14d3c530bb 100644
--- a/lib/private/App/AppStore/Bundles/EducationBundle.php
+++ b/lib/private/App/AppStore/Bundles/EducationBundle.php
@@ -1,5 +1,7 @@
 <?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/private/App/AppStore/Bundles/EnterpriseBundle.php b/lib/private/App/AppStore/Bundles/EnterpriseBundle.php
index fc2d43e03887e..fbc4019353bed 100644
--- a/lib/private/App/AppStore/Bundles/EnterpriseBundle.php
+++ b/lib/private/App/AppStore/Bundles/EnterpriseBundle.php
@@ -1,5 +1,7 @@
 <?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/private/App/AppStore/Bundles/GroupwareBundle.php b/lib/private/App/AppStore/Bundles/GroupwareBundle.php
index 93fa70268cd33..cddb18cf81786 100644
--- a/lib/private/App/AppStore/Bundles/GroupwareBundle.php
+++ b/lib/private/App/AppStore/Bundles/GroupwareBundle.php
@@ -1,5 +1,7 @@
 <?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/private/App/AppStore/Bundles/PublicSectorBundle.php b/lib/private/App/AppStore/Bundles/PublicSectorBundle.php
index 106a63530290c..06c5c6c2c39ab 100644
--- a/lib/private/App/AppStore/Bundles/PublicSectorBundle.php
+++ b/lib/private/App/AppStore/Bundles/PublicSectorBundle.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/App/AppStore/Bundles/SocialSharingBundle.php b/lib/private/App/AppStore/Bundles/SocialSharingBundle.php
index 40f0fb15977d3..013e8db3a8320 100644
--- a/lib/private/App/AppStore/Bundles/SocialSharingBundle.php
+++ b/lib/private/App/AppStore/Bundles/SocialSharingBundle.php
@@ -1,5 +1,7 @@
 <?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/private/App/AppStore/Fetcher/CategoryFetcher.php b/lib/private/App/AppStore/Fetcher/CategoryFetcher.php
index d7857d41bee83..60c0af82897b0 100644
--- a/lib/private/App/AppStore/Fetcher/CategoryFetcher.php
+++ b/lib/private/App/AppStore/Fetcher/CategoryFetcher.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/App/AppStore/Version/Version.php b/lib/private/App/AppStore/Version/Version.php
index 2d169a291f12a..5add30e84b5fe 100644
--- a/lib/private/App/AppStore/Version/Version.php
+++ b/lib/private/App/AppStore/Version/Version.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/AppFramework/Http.php b/lib/private/AppFramework/Http.php
index ee5a4397952b0..6f5b3b96b71c8 100644
--- a/lib/private/AppFramework/Http.php
+++ b/lib/private/AppFramework/Http.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/AppFramework/Middleware/PublicShare/Exceptions/NeedAuthenticationException.php b/lib/private/AppFramework/Middleware/PublicShare/Exceptions/NeedAuthenticationException.php
index 5df4009b09469..002364aa9a22f 100644
--- a/lib/private/AppFramework/Middleware/PublicShare/Exceptions/NeedAuthenticationException.php
+++ b/lib/private/AppFramework/Middleware/PublicShare/Exceptions/NeedAuthenticationException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/AppFramework/Middleware/Security/Exceptions/AppNotEnabledException.php b/lib/private/AppFramework/Middleware/Security/Exceptions/AppNotEnabledException.php
index 53fbaaf5ed20c..f59e4ab49686a 100644
--- a/lib/private/AppFramework/Middleware/Security/Exceptions/AppNotEnabledException.php
+++ b/lib/private/AppFramework/Middleware/Security/Exceptions/AppNotEnabledException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/AppFramework/Middleware/Security/Exceptions/CrossSiteRequestForgeryException.php b/lib/private/AppFramework/Middleware/Security/Exceptions/CrossSiteRequestForgeryException.php
index 0c6a28134caa0..a29e3961bfef8 100644
--- a/lib/private/AppFramework/Middleware/Security/Exceptions/CrossSiteRequestForgeryException.php
+++ b/lib/private/AppFramework/Middleware/Security/Exceptions/CrossSiteRequestForgeryException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/AppFramework/Middleware/Security/Exceptions/ExAppRequiredException.php b/lib/private/AppFramework/Middleware/Security/Exceptions/ExAppRequiredException.php
index 77bc7efebac8c..f0d79ef593afb 100644
--- a/lib/private/AppFramework/Middleware/Security/Exceptions/ExAppRequiredException.php
+++ b/lib/private/AppFramework/Middleware/Security/Exceptions/ExAppRequiredException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/AppFramework/Middleware/Security/Exceptions/LaxSameSiteCookieFailedException.php b/lib/private/AppFramework/Middleware/Security/Exceptions/LaxSameSiteCookieFailedException.php
index 0380c6781aa8b..c446d6a220bdd 100644
--- a/lib/private/AppFramework/Middleware/Security/Exceptions/LaxSameSiteCookieFailedException.php
+++ b/lib/private/AppFramework/Middleware/Security/Exceptions/LaxSameSiteCookieFailedException.php
@@ -1,5 +1,7 @@
 <?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/private/AppFramework/Middleware/Security/Exceptions/NotConfirmedException.php b/lib/private/AppFramework/Middleware/Security/Exceptions/NotConfirmedException.php
index ca30f736fbc4a..854189f1b6b7f 100644
--- a/lib/private/AppFramework/Middleware/Security/Exceptions/NotConfirmedException.php
+++ b/lib/private/AppFramework/Middleware/Security/Exceptions/NotConfirmedException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/AppFramework/Middleware/Security/Exceptions/NotLoggedInException.php b/lib/private/AppFramework/Middleware/Security/Exceptions/NotLoggedInException.php
index e5a7853a64b31..d2c5253442007 100644
--- a/lib/private/AppFramework/Middleware/Security/Exceptions/NotLoggedInException.php
+++ b/lib/private/AppFramework/Middleware/Security/Exceptions/NotLoggedInException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/AppFramework/OCS/V1Response.php b/lib/private/AppFramework/OCS/V1Response.php
index 1c2c25f5cb026..710a16fddf5ae 100644
--- a/lib/private/AppFramework/OCS/V1Response.php
+++ b/lib/private/AppFramework/OCS/V1Response.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/AppFramework/OCS/V2Response.php b/lib/private/AppFramework/OCS/V2Response.php
index efc9348eb3759..1a2170a7124e6 100644
--- a/lib/private/AppFramework/OCS/V2Response.php
+++ b/lib/private/AppFramework/OCS/V2Response.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Archive/Archive.php b/lib/private/Archive/Archive.php
index 874087fb16727..2887a341bbf1f 100644
--- a/lib/private/Archive/Archive.php
+++ b/lib/private/Archive/Archive.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Authentication/Exceptions/LoginRequiredException.php b/lib/private/Authentication/Exceptions/LoginRequiredException.php
index d18ec4f1fbf56..53aa7e0a2ed2d 100644
--- a/lib/private/Authentication/Exceptions/LoginRequiredException.php
+++ b/lib/private/Authentication/Exceptions/LoginRequiredException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Authentication/Exceptions/PasswordLoginForbiddenException.php b/lib/private/Authentication/Exceptions/PasswordLoginForbiddenException.php
index ec833a5a3d09e..0326eede983c8 100644
--- a/lib/private/Authentication/Exceptions/PasswordLoginForbiddenException.php
+++ b/lib/private/Authentication/Exceptions/PasswordLoginForbiddenException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Authentication/Exceptions/PasswordlessTokenException.php b/lib/private/Authentication/Exceptions/PasswordlessTokenException.php
index a11e9a5f8d5ea..a8d8181b5ae44 100644
--- a/lib/private/Authentication/Exceptions/PasswordlessTokenException.php
+++ b/lib/private/Authentication/Exceptions/PasswordlessTokenException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Authentication/Exceptions/TwoFactorAuthRequiredException.php b/lib/private/Authentication/Exceptions/TwoFactorAuthRequiredException.php
index 8873b2c9f85c6..d8366f3bb657b 100644
--- a/lib/private/Authentication/Exceptions/TwoFactorAuthRequiredException.php
+++ b/lib/private/Authentication/Exceptions/TwoFactorAuthRequiredException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Authentication/Exceptions/UserAlreadyLoggedInException.php b/lib/private/Authentication/Exceptions/UserAlreadyLoggedInException.php
index 257f59772fcaa..f8cec3d44a585 100644
--- a/lib/private/Authentication/Exceptions/UserAlreadyLoggedInException.php
+++ b/lib/private/Authentication/Exceptions/UserAlreadyLoggedInException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Authentication/LoginCredentials/Credentials.php b/lib/private/Authentication/LoginCredentials/Credentials.php
index e230f58e9182e..99e7827743e36 100644
--- a/lib/private/Authentication/LoginCredentials/Credentials.php
+++ b/lib/private/Authentication/LoginCredentials/Credentials.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Authentication/Token/TokenCleanupJob.php b/lib/private/Authentication/Token/TokenCleanupJob.php
index ee6abebc85090..5834d40cb52f1 100644
--- a/lib/private/Authentication/Token/TokenCleanupJob.php
+++ b/lib/private/Authentication/Token/TokenCleanupJob.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2022 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-only
diff --git a/lib/private/Collaboration/Collaborators/MailByMailPlugin.php b/lib/private/Collaboration/Collaborators/MailByMailPlugin.php
index 53f90e33c57f4..5c4156c6e1936 100644
--- a/lib/private/Collaboration/Collaborators/MailByMailPlugin.php
+++ b/lib/private/Collaboration/Collaborators/MailByMailPlugin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Collaboration/Collaborators/UserByMailPlugin.php b/lib/private/Collaboration/Collaborators/UserByMailPlugin.php
index 44c1a95221c7d..6c1367cdba841 100644
--- a/lib/private/Collaboration/Collaborators/UserByMailPlugin.php
+++ b/lib/private/Collaboration/Collaborators/UserByMailPlugin.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Color.php b/lib/private/Color.php
index 8e5cfb56c8330..7b8024891988b 100644
--- a/lib/private/Color.php
+++ b/lib/private/Color.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Comments/ManagerFactory.php b/lib/private/Comments/ManagerFactory.php
index ec30fb00d3f9e..d377bf5869695 100644
--- a/lib/private/Comments/ManagerFactory.php
+++ b/lib/private/Comments/ManagerFactory.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Contacts/ContactsMenu/Actions/LinkAction.php b/lib/private/Contacts/ContactsMenu/Actions/LinkAction.php
index cdaf9308bfc56..020d13996ebcd 100644
--- a/lib/private/Contacts/ContactsMenu/Actions/LinkAction.php
+++ b/lib/private/Contacts/ContactsMenu/Actions/LinkAction.php
@@ -1,5 +1,7 @@
 <?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/private/DB/OCSqlitePlatform.php b/lib/private/DB/OCSqlitePlatform.php
index 3e2b10e6e4073..d46aa694665fd 100644
--- a/lib/private/DB/OCSqlitePlatform.php
+++ b/lib/private/DB/OCSqlitePlatform.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/DB/QueryBuilder/CompositeExpression.php b/lib/private/DB/QueryBuilder/CompositeExpression.php
index c0da96fb3af0b..18adf242c8910 100644
--- a/lib/private/DB/QueryBuilder/CompositeExpression.php
+++ b/lib/private/DB/QueryBuilder/CompositeExpression.php
@@ -1,11 +1,12 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-
 namespace OC\DB\QueryBuilder;
 
 use OCP\DB\QueryBuilder\ICompositeExpression;
diff --git a/lib/private/DB/QueryBuilder/Literal.php b/lib/private/DB/QueryBuilder/Literal.php
index 8cdb071b52b81..438883b077ffa 100644
--- a/lib/private/DB/QueryBuilder/Literal.php
+++ b/lib/private/DB/QueryBuilder/Literal.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/DB/QueryBuilder/Parameter.php b/lib/private/DB/QueryBuilder/Parameter.php
index 11732c973fc8c..fa7b7dbd0a6c0 100644
--- a/lib/private/DB/QueryBuilder/Parameter.php
+++ b/lib/private/DB/QueryBuilder/Parameter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/DB/QueryBuilder/QueryFunction.php b/lib/private/DB/QueryBuilder/QueryFunction.php
index 6a91127f5d29e..fa456836a4095 100644
--- a/lib/private/DB/QueryBuilder/QueryFunction.php
+++ b/lib/private/DB/QueryBuilder/QueryFunction.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/DB/SQLiteMigrator.php b/lib/private/DB/SQLiteMigrator.php
index 40503ae17812d..160a0d6ccd717 100644
--- a/lib/private/DB/SQLiteMigrator.php
+++ b/lib/private/DB/SQLiteMigrator.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/DatabaseException.php b/lib/private/DatabaseException.php
index c0bb3eb71718f..70190d88bd216 100644
--- a/lib/private/DatabaseException.php
+++ b/lib/private/DatabaseException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/DatabaseSetupException.php b/lib/private/DatabaseSetupException.php
index 2e99eafa4ad85..03f769b3c74b6 100644
--- a/lib/private/DatabaseSetupException.php
+++ b/lib/private/DatabaseSetupException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Encryption/Exceptions/DecryptionFailedException.php b/lib/private/Encryption/Exceptions/DecryptionFailedException.php
index bdda5b381b6f7..126aec1370961 100644
--- a/lib/private/Encryption/Exceptions/DecryptionFailedException.php
+++ b/lib/private/Encryption/Exceptions/DecryptionFailedException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Encryption/Exceptions/EmptyEncryptionDataException.php b/lib/private/Encryption/Exceptions/EmptyEncryptionDataException.php
index a2829a8c09c2f..12d0b2ee04797 100644
--- a/lib/private/Encryption/Exceptions/EmptyEncryptionDataException.php
+++ b/lib/private/Encryption/Exceptions/EmptyEncryptionDataException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Encryption/Exceptions/EncryptionFailedException.php b/lib/private/Encryption/Exceptions/EncryptionFailedException.php
index 04ca6eba79cae..fc95f70ea7d58 100644
--- a/lib/private/Encryption/Exceptions/EncryptionFailedException.php
+++ b/lib/private/Encryption/Exceptions/EncryptionFailedException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Encryption/Exceptions/EncryptionHeaderKeyExistsException.php b/lib/private/Encryption/Exceptions/EncryptionHeaderKeyExistsException.php
index 52f488e29560a..c6136bc025598 100644
--- a/lib/private/Encryption/Exceptions/EncryptionHeaderKeyExistsException.php
+++ b/lib/private/Encryption/Exceptions/EncryptionHeaderKeyExistsException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Encryption/Exceptions/EncryptionHeaderToLargeException.php b/lib/private/Encryption/Exceptions/EncryptionHeaderToLargeException.php
index dace9527305d5..f31adb757e1e7 100644
--- a/lib/private/Encryption/Exceptions/EncryptionHeaderToLargeException.php
+++ b/lib/private/Encryption/Exceptions/EncryptionHeaderToLargeException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Encryption/Exceptions/ModuleAlreadyExistsException.php b/lib/private/Encryption/Exceptions/ModuleAlreadyExistsException.php
index 72ff00befc3eb..0d2350ca5dc42 100644
--- a/lib/private/Encryption/Exceptions/ModuleAlreadyExistsException.php
+++ b/lib/private/Encryption/Exceptions/ModuleAlreadyExistsException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Encryption/Exceptions/ModuleDoesNotExistsException.php b/lib/private/Encryption/Exceptions/ModuleDoesNotExistsException.php
index 8ec382f176dba..6b4db0dbc7750 100644
--- a/lib/private/Encryption/Exceptions/ModuleDoesNotExistsException.php
+++ b/lib/private/Encryption/Exceptions/ModuleDoesNotExistsException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Encryption/Exceptions/UnknownCipherException.php b/lib/private/Encryption/Exceptions/UnknownCipherException.php
index a64a413bf8e57..b70f008b9f0df 100644
--- a/lib/private/Encryption/Exceptions/UnknownCipherException.php
+++ b/lib/private/Encryption/Exceptions/UnknownCipherException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Federation/CloudFederationNotification.php b/lib/private/Federation/CloudFederationNotification.php
index d8f6d87f3e237..e0694c184af7c 100644
--- a/lib/private/Federation/CloudFederationNotification.php
+++ b/lib/private/Federation/CloudFederationNotification.php
@@ -1,5 +1,7 @@
 <?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/private/Files/Cache/CacheDependencies.php b/lib/private/Files/Cache/CacheDependencies.php
index 61d2a2f96466e..a115dcfbdbade 100644
--- a/lib/private/Files/Cache/CacheDependencies.php
+++ b/lib/private/Files/Cache/CacheDependencies.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Files/Cache/FailedCache.php b/lib/private/Files/Cache/FailedCache.php
index 83fb239ecb617..ce4d1a5eefb19 100644
--- a/lib/private/Files/Cache/FailedCache.php
+++ b/lib/private/Files/Cache/FailedCache.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Files/Cache/Wrapper/CachePermissionsMask.php b/lib/private/Files/Cache/Wrapper/CachePermissionsMask.php
index c2ecaaeaf07d3..905b418cdf48c 100644
--- a/lib/private/Files/Cache/Wrapper/CachePermissionsMask.php
+++ b/lib/private/Files/Cache/Wrapper/CachePermissionsMask.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Files/Config/CachedMountFileInfo.php b/lib/private/Files/Config/CachedMountFileInfo.php
index 1ea77a53e5fca..ae27b1e762d55 100644
--- a/lib/private/Files/Config/CachedMountFileInfo.php
+++ b/lib/private/Files/Config/CachedMountFileInfo.php
@@ -1,5 +1,7 @@
 <?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/private/Files/Config/UserMountCacheListener.php b/lib/private/Files/Config/UserMountCacheListener.php
index 2b1eecde971b8..6df2d08de77f2 100644
--- a/lib/private/Files/Config/UserMountCacheListener.php
+++ b/lib/private/Files/Config/UserMountCacheListener.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Files/Mount/CacheMountProvider.php b/lib/private/Files/Mount/CacheMountProvider.php
index 5f511701a5e28..b05f2aaee31d5 100644
--- a/lib/private/Files/Mount/CacheMountProvider.php
+++ b/lib/private/Files/Mount/CacheMountProvider.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Files/Mount/LocalHomeMountProvider.php b/lib/private/Files/Mount/LocalHomeMountProvider.php
index efd4e63831ccf..92b44eac1511c 100644
--- a/lib/private/Files/Mount/LocalHomeMountProvider.php
+++ b/lib/private/Files/Mount/LocalHomeMountProvider.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Files/Mount/MoveableMount.php b/lib/private/Files/Mount/MoveableMount.php
index 755733bf651c1..da1b50d2ee979 100644
--- a/lib/private/Files/Mount/MoveableMount.php
+++ b/lib/private/Files/Mount/MoveableMount.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Files/Notify/Change.php b/lib/private/Files/Notify/Change.php
index 6a94673987d47..445b978746a31 100644
--- a/lib/private/Files/Notify/Change.php
+++ b/lib/private/Files/Notify/Change.php
@@ -1,5 +1,7 @@
 <?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/private/Files/Search/SearchBinaryOperator.php b/lib/private/Files/Search/SearchBinaryOperator.php
index 3424a044179b5..ba8caa10cb88f 100644
--- a/lib/private/Files/Search/SearchBinaryOperator.php
+++ b/lib/private/Files/Search/SearchBinaryOperator.php
@@ -1,5 +1,7 @@
 <?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/private/Files/Search/SearchOrder.php b/lib/private/Files/Search/SearchOrder.php
index 5a036653f4e7f..345ca360af107 100644
--- a/lib/private/Files/Search/SearchOrder.php
+++ b/lib/private/Files/Search/SearchOrder.php
@@ -1,5 +1,7 @@
 <?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/private/Files/Search/SearchQuery.php b/lib/private/Files/Search/SearchQuery.php
index 9c1d7c5df78d2..1c38c1ef16277 100644
--- a/lib/private/Files/Search/SearchQuery.php
+++ b/lib/private/Files/Search/SearchQuery.php
@@ -1,5 +1,7 @@
 <?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/private/Files/Storage/CommonTest.php b/lib/private/Files/Storage/CommonTest.php
index 4bca8f90a38da..b1a939cc00b09 100644
--- a/lib/private/Files/Storage/CommonTest.php
+++ b/lib/private/Files/Storage/CommonTest.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Files/Storage/Storage.php b/lib/private/Files/Storage/Storage.php
index aa17c12b30999..e2beb5a8ac981 100644
--- a/lib/private/Files/Storage/Storage.php
+++ b/lib/private/Files/Storage/Storage.php
@@ -1,11 +1,12 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-
 namespace OC\Files\Storage;
 
 use OCP\Files\Cache\ICache;
diff --git a/lib/private/ForbiddenException.php b/lib/private/ForbiddenException.php
index e65576d27ad49..c03c27e59e8b1 100644
--- a/lib/private/ForbiddenException.php
+++ b/lib/private/ForbiddenException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/GlobalScale/Config.php b/lib/private/GlobalScale/Config.php
index 76753f781625e..4319a2fbb4285 100644
--- a/lib/private/GlobalScale/Config.php
+++ b/lib/private/GlobalScale/Config.php
@@ -1,5 +1,7 @@
 <?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/private/Hooks/BasicEmitter.php b/lib/private/Hooks/BasicEmitter.php
index 091334b71c8b9..775a7d47a8cbc 100644
--- a/lib/private/Hooks/BasicEmitter.php
+++ b/lib/private/Hooks/BasicEmitter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Hooks/Emitter.php b/lib/private/Hooks/Emitter.php
index 86eb410860c4d..b8c00a211fee6 100644
--- a/lib/private/Hooks/Emitter.php
+++ b/lib/private/Hooks/Emitter.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/IntegrityCheck/Exceptions/InvalidSignatureException.php b/lib/private/IntegrityCheck/Exceptions/InvalidSignatureException.php
index 25f8b0dcbf7d7..68038c2d0d243 100644
--- a/lib/private/IntegrityCheck/Exceptions/InvalidSignatureException.php
+++ b/lib/private/IntegrityCheck/Exceptions/InvalidSignatureException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/L10N/LanguageNotFoundException.php b/lib/private/L10N/LanguageNotFoundException.php
index 087a384e00eec..42053e70831d8 100644
--- a/lib/private/L10N/LanguageNotFoundException.php
+++ b/lib/private/L10N/LanguageNotFoundException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Lockdown/Filesystem/NullCache.php b/lib/private/Lockdown/Filesystem/NullCache.php
index dde483d7225d0..41e76bc0d972e 100644
--- a/lib/private/Lockdown/Filesystem/NullCache.php
+++ b/lib/private/Lockdown/Filesystem/NullCache.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Memcache/NullCache.php b/lib/private/Memcache/NullCache.php
index 11c17309b8750..0fc66db82f899 100644
--- a/lib/private/Memcache/NullCache.php
+++ b/lib/private/Memcache/NullCache.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Migration/NullOutput.php b/lib/private/Migration/NullOutput.php
index 8db7b950af8d3..f099d515c7749 100644
--- a/lib/private/Migration/NullOutput.php
+++ b/lib/private/Migration/NullOutput.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-only
diff --git a/lib/private/NeedsUpdateException.php b/lib/private/NeedsUpdateException.php
index da467d96299d4..cae8dc0047a8e 100644
--- a/lib/private/NeedsUpdateException.php
+++ b/lib/private/NeedsUpdateException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/NotSquareException.php b/lib/private/NotSquareException.php
index 7be7ad09521c5..2fb5e3dc6cfcc 100644
--- a/lib/private/NotSquareException.php
+++ b/lib/private/NotSquareException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/OCS/CoreCapabilities.php b/lib/private/OCS/CoreCapabilities.php
index 3d988a8662e76..2729cc738f46e 100644
--- a/lib/private/OCS/CoreCapabilities.php
+++ b/lib/private/OCS/CoreCapabilities.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/BMP.php b/lib/private/Preview/BMP.php
index f275aecf0cffd..b4d4d5829cb6e 100644
--- a/lib/private/Preview/BMP.php
+++ b/lib/private/Preview/BMP.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/Font.php b/lib/private/Preview/Font.php
index 79e537f6ffb65..85f5d1f78d153 100644
--- a/lib/private/Preview/Font.php
+++ b/lib/private/Preview/Font.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/GIF.php b/lib/private/Preview/GIF.php
index 941ef68648afd..be54bf8659cda 100644
--- a/lib/private/Preview/GIF.php
+++ b/lib/private/Preview/GIF.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/Illustrator.php b/lib/private/Preview/Illustrator.php
index bff556a31776d..937da1d9f8792 100644
--- a/lib/private/Preview/Illustrator.php
+++ b/lib/private/Preview/Illustrator.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/ImaginaryPDF.php b/lib/private/Preview/ImaginaryPDF.php
index d26c6d1b7ff84..2786700f5a7b6 100644
--- a/lib/private/Preview/ImaginaryPDF.php
+++ b/lib/private/Preview/ImaginaryPDF.php
@@ -1,10 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2020 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace OC\Preview;
 
 class ImaginaryPDF extends Imaginary {
diff --git a/lib/private/Preview/JPEG.php b/lib/private/Preview/JPEG.php
index a1a394f81c97a..97a6a0c94c159 100644
--- a/lib/private/Preview/JPEG.php
+++ b/lib/private/Preview/JPEG.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/Krita.php b/lib/private/Preview/Krita.php
index e96fac993aa57..8654698c125d4 100644
--- a/lib/private/Preview/Krita.php
+++ b/lib/private/Preview/Krita.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2020 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Preview/MSOffice2003.php b/lib/private/Preview/MSOffice2003.php
index a52e618d48436..977ebf467bfe2 100644
--- a/lib/private/Preview/MSOffice2003.php
+++ b/lib/private/Preview/MSOffice2003.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/MSOffice2007.php b/lib/private/Preview/MSOffice2007.php
index 317f2dcc7f12d..6ccf70be0c23d 100644
--- a/lib/private/Preview/MSOffice2007.php
+++ b/lib/private/Preview/MSOffice2007.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/MSOfficeDoc.php b/lib/private/Preview/MSOfficeDoc.php
index 2e1044395f1c5..479e91706896f 100644
--- a/lib/private/Preview/MSOfficeDoc.php
+++ b/lib/private/Preview/MSOfficeDoc.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/OpenDocument.php b/lib/private/Preview/OpenDocument.php
index f590eb6a59c6a..8eea9fecce7ba 100644
--- a/lib/private/Preview/OpenDocument.php
+++ b/lib/private/Preview/OpenDocument.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/PDF.php b/lib/private/Preview/PDF.php
index 9de14685925df..dc8b37079b365 100644
--- a/lib/private/Preview/PDF.php
+++ b/lib/private/Preview/PDF.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/PNG.php b/lib/private/Preview/PNG.php
index 49d0cd059ba62..5e2750c4f14cd 100644
--- a/lib/private/Preview/PNG.php
+++ b/lib/private/Preview/PNG.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/Photoshop.php b/lib/private/Preview/Photoshop.php
index b7209120530fa..dcb893626c8f9 100644
--- a/lib/private/Preview/Photoshop.php
+++ b/lib/private/Preview/Photoshop.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/Postscript.php b/lib/private/Preview/Postscript.php
index 68588647db42b..b03db86e5f825 100644
--- a/lib/private/Preview/Postscript.php
+++ b/lib/private/Preview/Postscript.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/SGI.php b/lib/private/Preview/SGI.php
index 78b1ea5828a50..64e1ed2863d2f 100644
--- a/lib/private/Preview/SGI.php
+++ b/lib/private/Preview/SGI.php
@@ -1,5 +1,7 @@
 <?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/private/Preview/StarOffice.php b/lib/private/Preview/StarOffice.php
index 9ea540dc9127c..e2d2b10dfcec5 100644
--- a/lib/private/Preview/StarOffice.php
+++ b/lib/private/Preview/StarOffice.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/TGA.php b/lib/private/Preview/TGA.php
index 675907b4e490d..24e55a09d90e7 100644
--- a/lib/private/Preview/TGA.php
+++ b/lib/private/Preview/TGA.php
@@ -1,5 +1,7 @@
 <?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/private/Preview/TIFF.php b/lib/private/Preview/TIFF.php
index cd81e611d0bd6..866e26cc3d8a1 100644
--- a/lib/private/Preview/TIFF.php
+++ b/lib/private/Preview/TIFF.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Preview/XBitmap.php b/lib/private/Preview/XBitmap.php
index c8337cc252dc6..95ea589835ae0 100644
--- a/lib/private/Preview/XBitmap.php
+++ b/lib/private/Preview/XBitmap.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/PreviewNotAvailableException.php b/lib/private/PreviewNotAvailableException.php
index 582f337acd1f2..3cc4b17f4ac7c 100644
--- a/lib/private/PreviewNotAvailableException.php
+++ b/lib/private/PreviewNotAvailableException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Remote/Api/ApiCollection.php b/lib/private/Remote/Api/ApiCollection.php
index a846eea08481c..b42c7c484ba08 100644
--- a/lib/private/Remote/Api/ApiCollection.php
+++ b/lib/private/Remote/Api/ApiCollection.php
@@ -1,5 +1,7 @@
 <?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/private/Remote/Api/ApiFactory.php b/lib/private/Remote/Api/ApiFactory.php
index f225ab1689401..8c908a2f91f43 100644
--- a/lib/private/Remote/Api/ApiFactory.php
+++ b/lib/private/Remote/Api/ApiFactory.php
@@ -1,5 +1,7 @@
 <?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/private/Remote/Api/NotFoundException.php b/lib/private/Remote/Api/NotFoundException.php
index 361d03d24edcc..e4dc514c3668e 100644
--- a/lib/private/Remote/Api/NotFoundException.php
+++ b/lib/private/Remote/Api/NotFoundException.php
@@ -1,5 +1,7 @@
 <?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/private/Remote/Credentials.php b/lib/private/Remote/Credentials.php
index 763e420c8c931..607c403b4bf8b 100644
--- a/lib/private/Remote/Credentials.php
+++ b/lib/private/Remote/Credentials.php
@@ -1,5 +1,7 @@
 <?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/private/Remote/User.php b/lib/private/Remote/User.php
index 18a4d8b30b829..a8f665154ad25 100644
--- a/lib/private/Remote/User.php
+++ b/lib/private/Remote/User.php
@@ -1,5 +1,7 @@
 <?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/private/Repair/AddCleanupUpdaterBackupsJob.php b/lib/private/Repair/AddCleanupUpdaterBackupsJob.php
index 55d703422ff24..731bf4537c710 100644
--- a/lib/private/Repair/AddCleanupUpdaterBackupsJob.php
+++ b/lib/private/Repair/AddCleanupUpdaterBackupsJob.php
@@ -1,5 +1,7 @@
 <?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/private/Repair/AddMetadataGenerationJob.php b/lib/private/Repair/AddMetadataGenerationJob.php
index ad5fb129ab1fb..f907144dc7d71 100644
--- a/lib/private/Repair/AddMetadataGenerationJob.php
+++ b/lib/private/Repair/AddMetadataGenerationJob.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Repair/AddMovePreviewJob.php b/lib/private/Repair/AddMovePreviewJob.php
index 1fe265fa1b668..84d32887f2841 100644
--- a/lib/private/Repair/AddMovePreviewJob.php
+++ b/lib/private/Repair/AddMovePreviewJob.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Repair/ClearFrontendCaches.php b/lib/private/Repair/ClearFrontendCaches.php
index 60be83efe631b..b5631b660cb2e 100644
--- a/lib/private/Repair/ClearFrontendCaches.php
+++ b/lib/private/Repair/ClearFrontendCaches.php
@@ -1,5 +1,7 @@
 <?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/private/Repair/ClearGeneratedAvatarCache.php b/lib/private/Repair/ClearGeneratedAvatarCache.php
index d48683dfb1e3b..cc71a5dc6e4a9 100644
--- a/lib/private/Repair/ClearGeneratedAvatarCache.php
+++ b/lib/private/Repair/ClearGeneratedAvatarCache.php
@@ -1,5 +1,7 @@
 <?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/private/Repair/ClearGeneratedAvatarCacheJob.php b/lib/private/Repair/ClearGeneratedAvatarCacheJob.php
index ff6a67480cd58..6637becd4a108 100644
--- a/lib/private/Repair/ClearGeneratedAvatarCacheJob.php
+++ b/lib/private/Repair/ClearGeneratedAvatarCacheJob.php
@@ -1,5 +1,7 @@
 <?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/private/Repair/Collation.php b/lib/private/Repair/Collation.php
index 346a5abc8153b..450b132ef47fc 100644
--- a/lib/private/Repair/Collation.php
+++ b/lib/private/Repair/Collation.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Repair/MoveUpdaterStepFile.php b/lib/private/Repair/MoveUpdaterStepFile.php
index 7155eed5689b4..28fe0db131403 100644
--- a/lib/private/Repair/MoveUpdaterStepFile.php
+++ b/lib/private/Repair/MoveUpdaterStepFile.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Repair/NC13/AddLogRotateJob.php b/lib/private/Repair/NC13/AddLogRotateJob.php
index 7ad9b3445b3c6..a44610dd07a78 100644
--- a/lib/private/Repair/NC13/AddLogRotateJob.php
+++ b/lib/private/Repair/NC13/AddLogRotateJob.php
@@ -1,5 +1,7 @@
 <?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/private/Repair/NC21/AddCheckForUserCertificatesJob.php b/lib/private/Repair/NC21/AddCheckForUserCertificatesJob.php
index e55dce7814d26..1890df81cf19c 100644
--- a/lib/private/Repair/NC21/AddCheckForUserCertificatesJob.php
+++ b/lib/private/Repair/NC21/AddCheckForUserCertificatesJob.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2020 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Repair/Owncloud/DropAccountTermsTable.php b/lib/private/Repair/Owncloud/DropAccountTermsTable.php
index 2420327a0372d..f848a99af57f9 100644
--- a/lib/private/Repair/Owncloud/DropAccountTermsTable.php
+++ b/lib/private/Repair/Owncloud/DropAccountTermsTable.php
@@ -1,5 +1,7 @@
 <?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/private/Repair/Owncloud/MoveAvatars.php b/lib/private/Repair/Owncloud/MoveAvatars.php
index f4ee9d751f25e..fd38fc79d6438 100644
--- a/lib/private/Repair/Owncloud/MoveAvatars.php
+++ b/lib/private/Repair/Owncloud/MoveAvatars.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/RepairException.php b/lib/private/RepairException.php
index bd6d4600bfbfb..9f57c2fabebc3 100644
--- a/lib/private/RepairException.php
+++ b/lib/private/RepairException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/ServerNotAvailableException.php b/lib/private/ServerNotAvailableException.php
index d24f16f30a03a..979032938aafe 100644
--- a/lib/private/ServerNotAvailableException.php
+++ b/lib/private/ServerNotAvailableException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/ServiceUnavailableException.php b/lib/private/ServiceUnavailableException.php
index f0fe3b48dbe74..f73f8bbc80a48 100644
--- a/lib/private/ServiceUnavailableException.php
+++ b/lib/private/ServiceUnavailableException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Settings/AuthorizedGroup.php b/lib/private/Settings/AuthorizedGroup.php
index a6039a66530fe..6949c0649aa7f 100644
--- a/lib/private/Settings/AuthorizedGroup.php
+++ b/lib/private/Settings/AuthorizedGroup.php
@@ -1,5 +1,7 @@
 <?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/private/Settings/Section.php b/lib/private/Settings/Section.php
index c67c4c07708df..8fb30165bcf62 100644
--- a/lib/private/Settings/Section.php
+++ b/lib/private/Settings/Section.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/Share/Constants.php b/lib/private/Share/Constants.php
index c55caee6f0a48..c816807f2807b 100644
--- a/lib/private/Share/Constants.php
+++ b/lib/private/Share/Constants.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Share20/Exception/BackendError.php b/lib/private/Share20/Exception/BackendError.php
index b2585367727a4..056629ee677d5 100644
--- a/lib/private/Share20/Exception/BackendError.php
+++ b/lib/private/Share20/Exception/BackendError.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Share20/Exception/InvalidShare.php b/lib/private/Share20/Exception/InvalidShare.php
index 8756455f9d227..eba781fa934f5 100644
--- a/lib/private/Share20/Exception/InvalidShare.php
+++ b/lib/private/Share20/Exception/InvalidShare.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/Share20/Exception/ProviderException.php b/lib/private/Share20/Exception/ProviderException.php
index cb79ab884b459..1c2dcae89aa5e 100644
--- a/lib/private/Share20/Exception/ProviderException.php
+++ b/lib/private/Share20/Exception/ProviderException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/StreamImage.php b/lib/private/StreamImage.php
index 00f14212c57a1..f4c444a2f0d3f 100644
--- a/lib/private/StreamImage.php
+++ b/lib/private/StreamImage.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2021 Nextcloud GmbH and Nextcloud contributors
diff --git a/lib/private/TaskProcessing/RemoveOldTasksBackgroundJob.php b/lib/private/TaskProcessing/RemoveOldTasksBackgroundJob.php
index 48a2cd256a895..1d10450e7bcf1 100644
--- a/lib/private/TaskProcessing/RemoveOldTasksBackgroundJob.php
+++ b/lib/private/TaskProcessing/RemoveOldTasksBackgroundJob.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/lib/private/User/DisabledUserException.php b/lib/private/User/DisabledUserException.php
index db8a23d202752..a126fee40d37f 100644
--- a/lib/private/User/DisabledUserException.php
+++ b/lib/private/User/DisabledUserException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-only
diff --git a/lib/private/User/LoginException.php b/lib/private/User/LoginException.php
index 6f0e98513ddea..e94b3b79b0e86 100644
--- a/lib/private/User/LoginException.php
+++ b/lib/private/User/LoginException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/lib/private/User/NoUserException.php b/lib/private/User/NoUserException.php
index c0a5c51b08da1..3df468211845f 100644
--- a/lib/private/User/NoUserException.php
+++ b/lib/private/User/NoUserException.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/ocs/v2.php b/ocs/v2.php
index c83d3c1b0d228..d2cc9cb6185ad 100644
--- a/ocs/v2.php
+++ b/ocs/v2.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/tests/databases-all-config.php b/tests/databases-all-config.php
index 210e75d3ab904..dd466610e258b 100644
--- a/tests/databases-all-config.php
+++ b/tests/databases-all-config.php
@@ -1,10 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 $CONFIG = [
 	'supportedDatabases' => [
 		'sqlite',
diff --git a/tests/lib/Comments/FakeManager.php b/tests/lib/Comments/FakeManager.php
index 518e4801d0b93..eadaee13054d3 100644
--- a/tests/lib/Comments/FakeManager.php
+++ b/tests/lib/Comments/FakeManager.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
diff --git a/tests/lib/Files/Cache/MoveFromCacheTraitTest.php b/tests/lib/Files/Cache/MoveFromCacheTraitTest.php
index c7e20f55fbef0..c929ac7ab679b 100644
--- a/tests/lib/Files/Cache/MoveFromCacheTraitTest.php
+++ b/tests/lib/Files/Cache/MoveFromCacheTraitTest.php
@@ -1,11 +1,12 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace Test\Files\Cache;
 
 use OC\Files\Cache\Cache;
diff --git a/tests/lib/Files/ObjectStore/LocalTest.php b/tests/lib/Files/ObjectStore/LocalTest.php
index d3e9ad5616451..f66114966a0d7 100644
--- a/tests/lib/Files/ObjectStore/LocalTest.php
+++ b/tests/lib/Files/ObjectStore/LocalTest.php
@@ -1,10 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace Test\Files\ObjectStore;
 
 use OC\Files\ObjectStore\StorageObjectStore;
diff --git a/tests/lib/Files/ObjectStore/ObjectStoreStoragesDifferentBucketTest.php b/tests/lib/Files/ObjectStore/ObjectStoreStoragesDifferentBucketTest.php
index d84df898a12a2..37cb8f47f2f7e 100644
--- a/tests/lib/Files/ObjectStore/ObjectStoreStoragesDifferentBucketTest.php
+++ b/tests/lib/Files/ObjectStore/ObjectStoreStoragesDifferentBucketTest.php
@@ -1,11 +1,12 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace Test\Files\ObjectStore;
 
 use OC\Files\ObjectStore\StorageObjectStore;
diff --git a/tests/lib/Files/ObjectStore/ObjectStoreStoragesSameBucketTest.php b/tests/lib/Files/ObjectStore/ObjectStoreStoragesSameBucketTest.php
index 5779c0c433626..b1a8de107161c 100644
--- a/tests/lib/Files/ObjectStore/ObjectStoreStoragesSameBucketTest.php
+++ b/tests/lib/Files/ObjectStore/ObjectStoreStoragesSameBucketTest.php
@@ -1,11 +1,12 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace Test\Files\ObjectStore;
 
 use OC\Files\ObjectStore\StorageObjectStore;
diff --git a/tests/lib/Files/Storage/CopyDirectoryTest.php b/tests/lib/Files/Storage/CopyDirectoryTest.php
index 141f6532a3d47..f542cc20e4a45 100644
--- a/tests/lib/Files/Storage/CopyDirectoryTest.php
+++ b/tests/lib/Files/Storage/CopyDirectoryTest.php
@@ -1,11 +1,12 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-
 namespace Test\Files\Storage;
 
 use OC\Files\Storage\PolyFill\CopyDirectory;
diff --git a/tests/lib/Files/Stream/DummyEncryptionWrapper.php b/tests/lib/Files/Stream/DummyEncryptionWrapper.php
index 89904e6de73e1..694ac3a25030f 100644
--- a/tests/lib/Files/Stream/DummyEncryptionWrapper.php
+++ b/tests/lib/Files/Stream/DummyEncryptionWrapper.php
@@ -1,11 +1,12 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2019-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-only
  */
-
 namespace Test\Files\Stream;
 
 use OC\Files\Stream\Encryption;
diff --git a/tests/lib/HookHelper.php b/tests/lib/HookHelper.php
index 19eca59ac80de..321d69aa9963e 100644
--- a/tests/lib/HookHelper.php
+++ b/tests/lib/HookHelper.php
@@ -1,11 +1,12 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace Test;
 
 use OC\Files\Filesystem;
diff --git a/tests/lib/Memcache/ArrayCacheTest.php b/tests/lib/Memcache/ArrayCacheTest.php
index 2e27994d12889..d652b51480c6c 100644
--- a/tests/lib/Memcache/ArrayCacheTest.php
+++ b/tests/lib/Memcache/ArrayCacheTest.php
@@ -1,11 +1,12 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace Test\Memcache;
 
 use OC\Memcache\ArrayCache;
diff --git a/tests/lib/Memcache/CasTraitTestClass.php b/tests/lib/Memcache/CasTraitTestClass.php
index f3dbd863b4084..b4c49c7886d2c 100644
--- a/tests/lib/Memcache/CasTraitTestClass.php
+++ b/tests/lib/Memcache/CasTraitTestClass.php
@@ -1,10 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace Test\Memcache;
 
 use OC\Memcache\CASTrait;
diff --git a/tests/lib/User/AvatarUserDummy.php b/tests/lib/User/AvatarUserDummy.php
index 001dabd24c6d9..77ca868da4bf1 100644
--- a/tests/lib/User/AvatarUserDummy.php
+++ b/tests/lib/User/AvatarUserDummy.php
@@ -1,11 +1,12 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2020-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-
 namespace Test\User;
 
 class AvatarUserDummy extends \Test\Util\User\Dummy {
diff --git a/tests/preseed-config.php b/tests/preseed-config.php
index f24c2a23ce140..1fc98a4226ac0 100644
--- a/tests/preseed-config.php
+++ b/tests/preseed-config.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2012-2016 ownCloud, Inc.
diff --git a/tests/redis-cluster.config.php b/tests/redis-cluster.config.php
index f749ebc81dc22..cbcdefc0f2334 100644
--- a/tests/redis-cluster.config.php
+++ b/tests/redis-cluster.config.php
@@ -1,5 +1,7 @@
 <?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/redis.config.php b/tests/redis.config.php
index dd135345abd47..7986b81773965 100644
--- a/tests/redis.config.php
+++ b/tests/redis.config.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
diff --git a/version.php b/version.php
index 598aa0fb50861..e9b4ce3677dc8 100644
--- a/version.php
+++ b/version.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.