diff --git a/lib/private/Server.php b/lib/private/Server.php
index b4fde5ec75207..57907706a8d7f 100644
--- a/lib/private/Server.php
+++ b/lib/private/Server.php
@@ -1107,7 +1107,7 @@ public function __construct($webRoot, \OC\Config $config) {
 		/** @deprecated 19.0.0 */
 		$this->registerDeprecatedAlias('LockingProvider', ILockingProvider::class);
 
-		$this->registerService(ILockManager::class, function (Server $c) {
+		$this->registerService(ILockManager::class, function (Server $c): LockManager {
 			return new LockManager();
 		});