diff --git a/build/psalm-baseline.xml b/build/psalm-baseline.xml
index 9d4ef09a30b5d..eacdc6318b6d6 100644
--- a/build/psalm-baseline.xml
+++ b/build/psalm-baseline.xml
@@ -1301,11 +1301,6 @@
       <code>$i</code>
     </UndefinedInterfaceMethod>
   </file>
-  <file src="apps/files/lib/Listener/LegacyLoadAdditionalScriptsAdapter.php">
-    <InvalidArgument occurrences="1">
-      <code>$legacyEvent</code>
-    </InvalidArgument>
-  </file>
   <file src="apps/files/lib/Service/DirectEditingService.php">
     <UndefinedInterfaceMethod occurrences="1">
       <code>getEditors</code>
@@ -1639,8 +1634,7 @@
     <InvalidArgument occurrences="1">
       <code>$files_list</code>
     </InvalidArgument>
-    <InvalidScalarArgument occurrences="3">
-      <code>$freeSpace</code>
+    <InvalidScalarArgument occurrences="1">
       <code>$maxUploadFilesize</code>
       <code>$maxUploadFilesize</code>
     </InvalidScalarArgument>
@@ -1681,11 +1675,6 @@
       <code>isSharable</code>
     </InvalidReturnType>
   </file>
-  <file src="apps/files_sharing/lib/Listener/LegacyBeforeTemplateRenderedListener.php">
-    <InvalidArgument occurrences="1">
-      <code>$legacyEvent</code>
-    </InvalidArgument>
-  </file>
   <file src="apps/files_sharing/lib/Middleware/SharingCheckMiddleware.php">
     <InvalidArgument occurrences="1">
       <code>$exception-&gt;getMessage()</code>
@@ -1967,10 +1956,8 @@
     </InvalidScalarArgument>
   </file>
   <file src="apps/sharebymail/lib/ShareByMailProvider.php">
-    <InvalidScalarArgument occurrences="4">
+    <InvalidScalarArgument occurrences="2">
       <code>$share-&gt;getId()</code>
-      <code>$shareId</code>
-      <code>$shareId</code>
       <code>(int)$data['id']</code>
     </InvalidScalarArgument>
   </file>
diff --git a/lib/private/AppFramework/Utility/SimpleContainer.php b/lib/private/AppFramework/Utility/SimpleContainer.php
index 598c66b6aba74..95693eddac220 100644
--- a/lib/private/AppFramework/Utility/SimpleContainer.php
+++ b/lib/private/AppFramework/Utility/SimpleContainer.php
@@ -52,6 +52,12 @@ public function __construct() {
 		$this->container = new Container();
 	}
 
+	/**
+	 * @psalm-suppress MoreSpecificImplementedParamType
+	 * @psalm-template T
+	 * @psalm-param class-string<T> $id
+	 * @psalm-return T
+	 */
 	public function get(string $id) {
 		return $this->query($id);
 	}
diff --git a/lib/private/EventDispatcher/SymfonyAdapter.php b/lib/private/EventDispatcher/SymfonyAdapter.php
index 6cd636afc55dd..0e33c8455d2c4 100644
--- a/lib/private/EventDispatcher/SymfonyAdapter.php
+++ b/lib/private/EventDispatcher/SymfonyAdapter.php
@@ -82,8 +82,8 @@ private static function detectEventAndName($a, $b) {
 	 * @param string $eventName The name of the event to dispatch. The name of
 	 *                              the event is the name of the method that is
 	 *                              invoked on listeners.
-	 * @param Event|null $event The event to pass to the event handlers/listeners
-	 *                              If not supplied, an empty Event instance is created
+	 * @param Event|GenericEvent|null $event The event to pass to the event handlers/listeners
+	 *                                       If not supplied, an empty Event instance is created
 	 *
 	 * @return object the emitted event
 	 * @deprecated 20.0.0
diff --git a/lib/private/Server.php b/lib/private/Server.php
index 13bbf972abb0a..a7bb3eb562596 100644
--- a/lib/private/Server.php
+++ b/lib/private/Server.php
@@ -982,7 +982,10 @@ public function __construct($webRoot, \OC\Config $config) {
 		$this->registerAlias(ITrustedDomainHelper::class, TrustedDomainHelper::class);
 		/** @deprecated 19.0.0 */
 		$this->registerDeprecatedAlias('Throttler', Throttler::class);
-		$this->registerService('IntegrityCodeChecker', function (ContainerInterface $c) {
+
+		/** @deprecated 24.0.0 */
+		$this->registerDeprecatedAlias('IntegrityCodeChecker', Checker::class);
+		$this->registerService(Checker::class, function (ContainerInterface $c) {
 			// IConfig and IAppManager requires a working database. This code
 			// might however be called when ownCloud is not yet setup.
 			if (\OC::$server->get(SystemConfig::class)->getValue('installed', false)) {
@@ -1156,8 +1159,10 @@ public function __construct($webRoot, \OC\Config $config) {
 		/** @deprecated 19.0.0 */
 		$this->registerDeprecatedAlias('CommentsManager', ICommentsManager::class);
 
-		$this->registerAlias(\OC_Defaults::class, 'ThemingDefaults');
-		$this->registerService('ThemingDefaults', function (Server $c) {
+		$this->registerAlias(\OC_Defaults::class, ThemingDefaults::class);
+		/** @deprecated 24.0.0 */
+		$this->registerDeprecatedAlias('ThemingDefaults', ThemingDefaults::class);
+		$this->registerService(ThemingDefaults::class, function (Server $c) {
 			/*
 			 * Dark magic for autoloader.
 			 * If we do a class_exists it will try to load the class which will
@@ -1206,7 +1211,9 @@ public function __construct($webRoot, \OC\Config $config) {
 		$this->registerDeprecatedAlias('EventDispatcher', \OC\EventDispatcher\SymfonyAdapter::class);
 		$this->registerAlias(EventDispatcherInterface::class, \OC\EventDispatcher\SymfonyAdapter::class);
 
-		$this->registerService('CryptoWrapper', function (ContainerInterface $c) {
+		/** @deprecated 24.0.0 */
+		$this->registerDeprecatedAlias('CryptoWrapper', CryptoWrapper::class);
+		$this->registerService(CryptoWrapper::class, function (ContainerInterface $c) {
 			// FIXME: Instantiiated here due to cyclic dependency
 			$request = new Request(
 				[
@@ -1261,7 +1268,7 @@ public function __construct($webRoot, \OC\Config $config) {
 				$c->get(SymfonyAdapter::class),
 				$c->get(IMailer::class),
 				$c->get(IURLGenerator::class),
-				$c->get('ThemingDefaults'),
+				$c->get(ThemingDefaults::class),
 				$c->get(IEventDispatcher::class),
 				$c->get(IUserSession::class),
 				$c->get(KnownUserService::class)
@@ -1302,7 +1309,9 @@ public function __construct($webRoot, \OC\Config $config) {
 			);
 		});
 
-		$this->registerService('LockdownManager', function (ContainerInterface $c) {
+		/** @deprecated 24.0.0 */
+		$this->registerDeprecatedAlias('LockdownManager', LockdownManager::class);
+		$this->registerService(LockdownManager::class, function (ContainerInterface $c): LockdownManager {
 			return new LockdownManager(function () use ($c) {
 				return $c->get(ISession::class);
 			});
@@ -1645,6 +1654,7 @@ public function getUserSession() {
 	 * @deprecated 20.0.0
 	 */
 	public function getSession() {
+		/** @psalm-suppress UndefinedInterfaceMethod */
 		return $this->get(IUserSession::class)->getSession();
 	}
 
@@ -1653,6 +1663,7 @@ public function getSession() {
 	 */
 	public function setSession(\OCP\ISession $session) {
 		$this->get(SessionStorage::class)->setSession($session);
+		/** @psalm-suppress UndefinedInterfaceMethod */
 		$this->get(IUserSession::class)->setSession($session);
 		$this->get(Store::class)->setSession($session);
 	}
@@ -1763,7 +1774,7 @@ public function getMemCacheFactory() {
 	 * @deprecated 20.0.0
 	 */
 	public function getGetRedisFactory() {
-		return $this->get('RedisFactory');
+		return $this->get(RedisFactory::class);
 	}
 
 
@@ -1974,6 +1985,7 @@ public function getWebRoot() {
 	 * @deprecated 20.0.0
 	 */
 	public function getOcsClient() {
+		/** @psalm-suppress UndefinedClass */
 		return $this->get('OcsClient');
 	}
 
@@ -2117,11 +2129,11 @@ public function getCommentsManager() {
 	}
 
 	/**
-	 * @return \OCA\Theming\ThemingDefaults
+	 * @return ThemingDefaults
 	 * @deprecated 20.0.0
 	 */
 	public function getThemingDefaults() {
-		return $this->get('ThemingDefaults');
+		return $this->get(ThemingDefaults::class);
 	}
 
 	/**
@@ -2129,15 +2141,15 @@ public function getThemingDefaults() {
 	 * @deprecated 20.0.0
 	 */
 	public function getIntegrityCodeChecker() {
-		return $this->get('IntegrityCodeChecker');
+		return $this->get(Checker::class);
 	}
 
 	/**
-	 * @return \OC\Session\CryptoWrapper
+	 * @return CryptoWrapper
 	 * @deprecated 20.0.0
 	 */
 	public function getSessionCryptoWrapper() {
-		return $this->get('CryptoWrapper');
+		return $this->get(CryptoWrapper::class);
 	}
 
 	/**
@@ -2243,7 +2255,7 @@ public function getAutoCompleteManager() {
 	 * @deprecated 20.0.0
 	 */
 	public function getLDAPProvider() {
-		return $this->get('LDAPProvider');
+		return $this->get(ILDAPProvider::class);
 	}
 
 	/**
@@ -2269,7 +2281,7 @@ public function getAppDataDir($app) {
 	 * @deprecated 20.0.0
 	 */
 	public function getLockdownManager() {
-		return $this->get('LockdownManager');
+		return $this->get(LockdownManager::class);
 	}
 
 	/**
diff --git a/lib/private/Template/Base.php b/lib/private/Template/Base.php
index 2de8c7ad5b18c..66f51a6e9d88d 100644
--- a/lib/private/Template/Base.php
+++ b/lib/private/Template/Base.php
@@ -30,7 +30,6 @@
 namespace OC\Template;
 
 use OCP\Defaults;
-use Throwable;
 
 class Base {
 	private $template; // The template
@@ -92,7 +91,7 @@ protected function getCoreTemplateDirs($theme, $serverRoot) {
 	/**
 	 * Assign variables
 	 * @param string $key key
-	 * @param array|bool|integer|string|Throwable $value value
+	 * @param mixed $value value
 	 * @return bool
 	 *
 	 * This function assigns a variable. It can be accessed via $_[$key] in