diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 000000000..c7f81110f
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,13 @@
+# SPDX-FileCopyrightText: 2019 Nextcloud GmbH and Nextcloud contributors
+# SPDX-License-Identifier: AGPL-3.0-or-later
+
+[*]
+charset = utf-8
+indent_style = tab
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[{package.json,webpack.config.js}]
+indent_style = space
+indent_size = 2
diff --git a/appinfo/routes.php b/appinfo/routes.php
index b0e56b99f..d59500c69 100644
--- a/appinfo/routes.php
+++ b/appinfo/routes.php
@@ -88,7 +88,7 @@
 		['name' => 'Icon#getLocalIconList', 'url' => '/api/v2/icon/list', 'verb' => 'GET'],
 
 		//
-		['name' => 'Vault#preflighted_cors', 'url' => '/api/v2/{path}', 'verb' => 'OPTIONS', 'requirements' => array('path' => '.+')],
+		['name' => 'Vault#preflighted_cors', 'url' => '/api/v2/{path}', 'verb' => 'OPTIONS', 'requirements' => ['path' => '.+']],
 		//Internal API
 		['name' => 'Internal#remind', 'url' => '/api/internal/notifications/remind/{credential_id}', 'verb' => 'POST'],
 		['name' => 'Internal#read', 'url' => '/api/internal/notifications/read/{credential_id}', 'verb' => 'DELETE'],
diff --git a/composer.json b/composer.json
index fe3f573dc..c86410a7e 100644
--- a/composer.json
+++ b/composer.json
@@ -6,5 +6,12 @@
             "email": "brantje@gmail.com"
         }
     ],
-    "require": {}
+    "license": "AGPL-3.0-or-later",
+    "scripts": {
+        "rector:check": "rector --dry-run --clear-cache",
+        "rector:fix": "rector"
+    },
+    "require-dev": {
+        "rector/rector": "^2.1"
+    }
 }
diff --git a/lib/Activity.php b/lib/Activity.php
index 73adae07b..c9c8c1ccf 100644
--- a/lib/Activity.php
+++ b/lib/Activity.php
@@ -227,18 +227,15 @@ public function getSpecialParameterList($app, $text) {
 	 * @param string $type
 	 * @return string|false
 	 */
-	public function getTypeIcon($type) {
-		switch ($type) {
-			case self::TYPE_ITEM_ACTION:
-			case self::TYPE_ITEM_EXPIRED:
-				return 'icon-password';
-			case self::TYPE_ITEM_SHARED:
-				return 'icon-share';
-			case self::TYPE_ITEM_RENAMED:
-				return 'icon-rename';
-		}
-		return false;
-	}
+	public function getTypeIcon($type)
+    {
+        return match ($type) {
+            self::TYPE_ITEM_ACTION, self::TYPE_ITEM_EXPIRED => 'icon-password',
+            self::TYPE_ITEM_SHARED => 'icon-share',
+            self::TYPE_ITEM_RENAMED => 'icon-rename',
+            default => false,
+        };
+    }
 
 	/**
 	 * The extension can define the parameter grouping by returning the index as integer.
diff --git a/lib/AppInfo/Application.php b/lib/AppInfo/Application.php
index ce0697dd3..df6cd4d7c 100644
--- a/lib/AppInfo/Application.php
+++ b/lib/AppInfo/Application.php
@@ -69,13 +69,9 @@ public function register(IRegistrationContext $context): void {
 
 		$context->registerSearchProvider(Provider::class);
 
-		$context->registerService(View::class, function () {
-			return new View('');
-		}, false);
+		$context->registerService(View::class, fn() => new View(''), false);
 
-		$context->registerService('isCLI', function () {
-			return \OC::$CLI;
-		});
+		$context->registerService('isCLI', fn() => \OC::$CLI);
 
 		$context->registerMiddleware(ShareMiddleware::class);
 		$context->registerMiddleware(APIMiddleware::class);
@@ -106,20 +102,16 @@ public function register(IRegistrationContext $context): void {
 		});
 
 
-		$context->registerService('CronService', function (ContainerInterface $c) {
-			return new CronService(
+		$context->registerService('CronService', fn(ContainerInterface $c) => new CronService(
 				$c->get(CredentialService::class),
 				$c->get(LoggerInterface::class),
 				$c->get(Utils::class),
 				$c->get(NotificationService::class),
 				$c->get(ActivityService::class),
 				$c->get(IDBConnection::class)
-			);
-		});
+			));
 
-		$context->registerService('Logger', function (ContainerInterface $c) {
-			return $c->get(ServerContainer::class)->getLogger();
-		});
+		$context->registerService('Logger', fn(ContainerInterface $c) => $c->get(ServerContainer::class)->getLogger());
 	}
 
 	public function boot(IBootContext $context): void {
diff --git a/lib/BackgroundJob/ExpireCredentials.php b/lib/BackgroundJob/ExpireCredentials.php
index a0b431445..89dbd633a 100644
--- a/lib/BackgroundJob/ExpireCredentials.php
+++ b/lib/BackgroundJob/ExpireCredentials.php
@@ -45,7 +45,7 @@ class ExpireCredentials extends TimedJob {
 	public function __construct(
 		ITimeFactory $timeFactory,
 		protected IConfig $config,
-		private CronService $cronService,
+		private readonly CronService $cronService,
 	) {
         parent::__construct($timeFactory);
 
diff --git a/lib/Controller/AdminController.php b/lib/Controller/AdminController.php
index 6ea16b0db..7c8028479 100644
--- a/lib/Controller/AdminController.php
+++ b/lib/Controller/AdminController.php
@@ -28,19 +28,17 @@
 
 
 class AdminController extends ApiController {
-	private $userId;
-
 	public function __construct(
 		$AppName,
 		IRequest $request,
-		$UserId,
-		private VaultService $vaultService,
-		private CredentialService $credentialService,
-		private FileService $fileService,
-		private CredentialRevisionService $revisionService,
-		private DeleteVaultRequestService $deleteVaultRequestService,
-		private IConfig $config,
-		private IUserManager $userManager,
+		private $userId,
+		private readonly VaultService $vaultService,
+		private readonly CredentialService $credentialService,
+		private readonly FileService $fileService,
+		private readonly CredentialRevisionService $revisionService,
+		private readonly DeleteVaultRequestService $deleteVaultRequestService,
+		private readonly IConfig $config,
+		private readonly IUserManager $userManager,
 	) {
 		parent::__construct(
 			$AppName,
@@ -48,7 +46,6 @@ public function __construct(
 			'GET, POST, DELETE, PUT, PATCH, OPTIONS',
 			'Authorization, Content-Type, Accept',
 			86400);
-		$this->userId = $UserId;
 
 	}
 
@@ -121,7 +118,7 @@ public function acceptRequestDeletion($vault_guid, $requested_by){
 		$req = $this->deleteVaultRequestService->getDeleteRequestForVault($vault_guid);
 		try{
 			$vault = $this->vaultService->getByGuid($vault_guid, $requested_by);
-		} catch (\Exception $e){
+		} catch (\Exception){
 			//Ignore
 		}
 
@@ -175,7 +172,7 @@ public function deleteRequestDeletion($vault_guid) {
 		$result = false;
 		try {
 			$delete_request = $this->deleteVaultRequestService->getDeleteRequestForVault($vault_guid);
-		} catch (\Exception $exception){
+		} catch (\Exception){
 			// Ignore it
 		}
 
diff --git a/lib/Controller/CredentialController.php b/lib/Controller/CredentialController.php
index 75f442e51..accffb568 100644
--- a/lib/Controller/CredentialController.php
+++ b/lib/Controller/CredentialController.php
@@ -28,17 +28,15 @@
 
 
 class CredentialController extends ApiController {
-	private $userId;
-
 	public function __construct(
 		$AppName,
 		IRequest $request,
-		$userId,
-		private CredentialService $credentialService,
-		private ActivityService $activityService,
-		private CredentialRevisionService $credentialRevisionService,
-		private ShareService $sharingService,
-		private SettingsService $settings,
+		private $userId,
+		private readonly CredentialService $credentialService,
+		private readonly ActivityService $activityService,
+		private readonly CredentialRevisionService $credentialRevisionService,
+		private readonly ShareService $sharingService,
+		private readonly SettingsService $settings,
 	) {
 		parent::__construct(
 			$AppName,
@@ -46,7 +44,6 @@ public function __construct(
 			'GET, POST, DELETE, PUT, PATCH, OPTIONS',
 			'Authorization, Content-Type, Accept',
 			86400);
-		$this->userId = $userId;
 	}
 
 
@@ -199,7 +196,7 @@ public function updateCredential($changed, $created,
 
 		try {
 			$acl_list = $this->sharingService->getCredentialAclList($storedCredential->getGuid());
-		} catch (\Exception $exception) {
+		} catch (\Exception) {
 			// Just check if we have an acl list
 		}
 		if (!empty($acl_list)) {
@@ -264,7 +261,7 @@ public function updateCredential($changed, $created,
 	public function deleteCredential($credential_guid) {
 		try {
 			$credential = $this->credentialService->getCredentialByGUID($credential_guid, $this->userId);
-		} catch (\Exception $e) {
+		} catch (\Exception) {
 			return new NotFoundJSONResponse();
 		}
 		if ($credential instanceof Credential) {
@@ -285,7 +282,7 @@ public function deleteCredential($credential_guid) {
 	public function getRevision($credential_guid) {
 		try {
 			$credential = $this->credentialService->getCredentialByGUID($credential_guid);
-		} catch (\Exception $ex) {
+		} catch (\Exception) {
 			return new NotFoundJSONResponse();
 		}
 		// If the request was made by the owner of the credential
@@ -320,7 +317,7 @@ public function updateRevision($revision_id, $credential_data) {
 		$revision = null;
 		try {
 			$revision = $this->credentialRevisionService->getRevision($revision_id);
-		} catch (\Exception $exception) {
+		} catch (\Exception) {
 			return new JSONResponse([]);
 		}
 
diff --git a/lib/Controller/FileController.php b/lib/Controller/FileController.php
index 8655fba01..38ad70eb3 100644
--- a/lib/Controller/FileController.php
+++ b/lib/Controller/FileController.php
@@ -18,14 +18,12 @@
 use Psr\Log\LoggerInterface;
 
 class FileController extends ApiController {
-	private $userId;
-
 	public function __construct(
 		$AppName,
 		IRequest $request,
-		$UserId,
-		private FileService $fileService,
-		private LoggerInterface $logger,
+		private $userId,
+		private readonly FileService $fileService,
+		private readonly LoggerInterface $logger,
 	) {
 		parent::__construct(
 			$AppName,
@@ -33,7 +31,6 @@ public function __construct(
 			'GET, POST, DELETE, PUT, PATCH, OPTIONS',
 			'Authorization, Content-Type, Accept',
 			86400);
-		$this->userId = $UserId;
 	}
 
 
@@ -72,9 +69,9 @@ public function deleteFile($file_id) {
 	 * @NoAdminRequired
 	 * @NoCSRFRequired
 	 */
-	public function deleteFiles($file_ids) {
+	public function deleteFiles(string $file_ids) {
 		$failed_file_ids = [];
-		if ($file_ids != null && !empty($file_ids)) {
+		if (!empty($file_ids)) {
 			$decoded_file_ids = json_decode($file_ids);
 			foreach ($decoded_file_ids as $file_id) {
 				try {
@@ -97,7 +94,7 @@ public function deleteFiles($file_ids) {
 	public function updateFile($file_id, $file_data, $filename) {
 		try {
 			$file = $this->fileService->getFile($file_id, $this->userId);
-		} catch (\Exception $doesNotExistException) {
+		} catch (\Exception) {
 
 		}
 		if ($file) {
diff --git a/lib/Controller/IconController.php b/lib/Controller/IconController.php
index 0a9c23e5d..1fab0b34d 100644
--- a/lib/Controller/IconController.php
+++ b/lib/Controller/IconController.php
@@ -24,16 +24,15 @@
 use OCP\IURLGenerator;
 
 class IconController extends ApiController {
-	private $userId;
 	const ICON_CACHE_OFFSET = 2592000;  // 3600 * 24 * 30
 
 	public function __construct(
 		$AppName,
 		IRequest $request,
-		$UserId,
-		private CredentialService $credentialService,
-		private AppManager $am,
-		private IURLGenerator $urlGenerator,
+		private $userId,
+		private readonly CredentialService $credentialService,
+		private readonly AppManager $am,
+		private readonly IURLGenerator $urlGenerator,
 	) {
 		parent::__construct(
 			$AppName,
@@ -41,8 +40,6 @@ public function __construct(
 			'GET, POST, DELETE, PUT, PATCH, OPTIONS',
 			'Authorization, Content-Type, Accept',
 			86400);
-		$this->userId = $UserId;
-
 	}
 
 	/**
@@ -78,7 +75,7 @@ public function getIcon($base64Url, $credentialId) {
 			try {
 				$credential = $this->credentialService->getCredentialById($credentialId, $this->userId);
 				$credential = $credential->jsonSerialize();
-			} catch (DoesNotExistException $e) {
+			} catch (DoesNotExistException) {
 				// Credential is not found, continue
 				$credential = false;
 			}
@@ -97,14 +94,14 @@ public function getIcon($base64Url, $credentialId) {
 				$data = $icon->icoData;
 				$type = $icon->icoType;
 			}
-		} catch (\InvalidArgumentException $e) {
+		} catch (\InvalidArgumentException) {
 			//no need to do stuff in catch
 			//if IconService fails the predefined $data and $type are used
 		}
 
 		if (isset($credential) && $credential['user_id'] == $this->userId) {
 			$iconData = [
-				'type' => ($type) ? $type : 'x-icon',
+				'type' => $type ?: 'x-icon',
 				'content' => base64_encode($data)
 			];
 			$credential['icon'] = json_encode($iconData);
@@ -112,7 +109,7 @@ public function getIcon($base64Url, $credentialId) {
 				if ($credential) {
 					$this->credentialService->updateCredential($credential);
 				}
-			} catch (DriverException $exception) {
+			} catch (DriverException) {
 				/**
 				 * @FIXME Syntax error or access violation: 1118 Row size too large
 				 * This happens when favicons are quite big.
@@ -146,7 +143,7 @@ public function getLocalIconList() {
 		$icons = [];
 		foreach ($result as $icon) {
 			$iconPath = $icon;
-			$path = explode('passman/', $iconPath);
+			$path = explode('passman/', (string) $iconPath);
 			$pack = explode('/', $path[1])[2];
 			$mime = mime_content_type($iconPath);
 			if ($mime !== 'directory') {
diff --git a/lib/Controller/InternalController.php b/lib/Controller/InternalController.php
index 6a7614525..6e63209b1 100644
--- a/lib/Controller/InternalController.php
+++ b/lib/Controller/InternalController.php
@@ -21,16 +21,14 @@
 use OCP\IRequest;
 
 class InternalController extends ApiController {
-	private $userId;
-
 	public function __construct(
 		$AppName,
 		IRequest $request,
-		$UserId,
-		private CredentialService $credentialService,
-		private NotificationService $notificationService,
-		private IConfig $config,
-		private IAppManager $appManager,
+		private $userId,
+		private readonly CredentialService $credentialService,
+		private readonly NotificationService $notificationService,
+		private readonly IConfig $config,
+		private readonly IAppManager $appManager,
 	) {
 		parent::__construct(
 			$AppName,
@@ -38,7 +36,6 @@ public function __construct(
 			'GET, POST, DELETE, PUT, PATCH, OPTIONS',
 			'Authorization, Content-Type, Accept',
 			86400);
-		$this->userId = $UserId;
 	}
 
 	/**
@@ -48,7 +45,7 @@ public function remind($credential_id) {
 		$credential = $this->credentialService->getCredentialById($credential_id, $this->userId);
 		if ($credential) {
 			$credential->setExpireTime(time() + (24 * 60 * 60));
-			$this->credentialService->upd($credential);
+			$this->credentialService->updateCredentialEntity($credential);
 
 			$this->notificationService->markNotificationOfCredentialAsProcessed($credential_id, $this->userId);
 		}
@@ -72,7 +69,7 @@ public function read($credential_id) {
 		$credential = $this->credentialService->getCredentialById($credential_id, $this->userId);
 		if ($credential) {
 			$credential->setExpireTime(0);
-			$this->credentialService->upd($credential);
+			$this->credentialService->updateCredentialEntity($credential);
 
 			$this->notificationService->markNotificationOfCredentialAsProcessed($credential_id, $this->userId);
 		}
diff --git a/lib/Controller/SettingsController.php b/lib/Controller/SettingsController.php
index 1c97b882e..ab5e21cba 100644
--- a/lib/Controller/SettingsController.php
+++ b/lib/Controller/SettingsController.php
@@ -24,8 +24,8 @@ public function __construct(
 		$AppName,
 		IRequest $request,
 		private $userId,
-		private SettingsService $settings,
-		private IL10N $l,
+		private readonly SettingsService $settings,
+		private readonly IL10N $l,
 	) {
 		parent::__construct(
 			$AppName,
diff --git a/lib/Controller/ShareController.php b/lib/Controller/ShareController.php
index 91883249c..02eb203e5 100644
--- a/lib/Controller/ShareController.php
+++ b/lib/Controller/ShareController.php
@@ -35,25 +35,23 @@
 
 
 class ShareController extends ApiController {
-	private $userId;
-
 	private $limit = 50;
 	private $offset = 0;
 
 	public function __construct(
 		$AppName,
 		IRequest $request,
-		$UserId,
-		private IGroupManager $groupManager,
-		private IUserManager $userManager,
-		private ActivityService $activityService,
-		private VaultService $vaultService,
-		private ShareService $shareService,
-		private CredentialService $credentialService,
-		private NotificationService $notificationService,
-		private FileService $fileService,
-		private SettingsService $settings,
-		private IManager $manager,
+		private $userId,
+		private readonly IGroupManager $groupManager,
+		private readonly IUserManager $userManager,
+		private readonly ActivityService $activityService,
+		private readonly VaultService $vaultService,
+		private readonly ShareService $shareService,
+		private readonly CredentialService $credentialService,
+		private readonly NotificationService $notificationService,
+		private readonly FileService $fileService,
+		private readonly SettingsService $settings,
+		private readonly IManager $manager,
 	) {
 		parent::__construct(
 			$AppName,
@@ -61,8 +59,6 @@ public function __construct(
 			'GET, POST, DELETE, PUT, PATCH, OPTIONS',
 			'Authorization, Content-Type, Accept',
 			86400);
-
-		$this->userId = $UserId;
 	}
 
 
@@ -77,13 +73,13 @@ public function __construct(
 	public function createPublicShare($item_id, $item_guid, $permissions, $expire_timestamp, $expire_views) {
 		try {
 			$credential = $this->credentialService->getCredentialByGUID($item_guid);
-		} catch (\Exception $exception) {
+		} catch (\Exception) {
 			return new NotFoundResponse();
 		}
 
 		try {
 			$acl = $this->shareService->getACL(null, $item_guid);
-		} catch (\Exception $exception) {
+		} catch (\Exception) {
 			$acl = new SharingACL();
 		}
 
@@ -125,14 +121,14 @@ public function applyIntermediateShare($item_id, $item_guid, $vaults, $permissio
 			if (count($shareRequests) > 0) {
 				return new JSONResponse(['error' => 'User got already pending requests']);
 			}
-		} catch (\Exception $exception) {
+		} catch (\Exception) {
 			// no need to catch this
 		}
 
 		$acl = null;
 		try {
 			$acl = $this->shareService->getCredentialAclForUser($first_vault['user_id'], $item_guid);
-		} catch (\Exception $exception) {
+		} catch (\Exception) {
 			// no need to catch this
 		}
 
@@ -147,7 +143,7 @@ public function applyIntermediateShare($item_id, $item_guid, $vaults, $permissio
 				if (!in_array($vault->getTargetUserId(), $processed_users)) {
 					$target_user = $vault->getTargetUserId();
 					$notification = [
-						'from_user' => ucfirst($this->userId->getDisplayName()),
+						'from_user' => ucfirst((string) $this->userId->getDisplayName()),
 						'credential_label' => $credential->getLabel(),
 						'credential_id' => $credential->getId(),
 						'item_id' => $credential->getId(),
@@ -216,14 +212,14 @@ public function unshareCredentialFromUser($item_guid, $user_id) {
 		$sr = null;
 		try {
 			$acl = $this->shareService->getCredentialAclForUser($user_id, $item_guid);
-		} catch (\Exception $e) {
-
+		} catch (\Exception) {
+			// no need to handle this
 		}
 		try {
 			$shareRequests = $this->shareService->getPendingShareRequestsForCredential($item_guid, $user_id);
 			$sr = array_pop($shareRequests);
-		} catch (\Exception $e) {
-			// no need to catch this
+		} catch (\Exception) {
+			// no need to handle this
 		}
 
 		if ($sr) {
@@ -275,7 +271,7 @@ public function getVaultsByUser($user_id) {
 	public function savePendingRequest($item_guid, $target_vault_guid, $final_shared_key) {
 		try {
 			$sr = $this->shareService->getRequestByGuid($item_guid, $target_vault_guid);
-		} catch (\Exception $ex) {
+		} catch (\Exception) {
 			return new NotFoundResponse();
 		}
 
@@ -286,7 +282,7 @@ public function savePendingRequest($item_guid, $target_vault_guid, $final_shared
 		$this->manager->markProcessed($notification);
 
 		$notification = [
-			'from_user' => ucfirst($this->userId->getDisplayName()),
+			'from_user' => ucfirst((string) $this->userId->getDisplayName()),
 			'credential_label' => $this->credentialService->getCredentialLabelById($sr->getItemId())->getLabel(),
 			'target_user' => $sr->getFromUserId(),
 			'req_id' => $sr->getId()
@@ -315,7 +311,7 @@ public function getPendingRequests() {
 				$results[] = $result;
 			}
 			return new JSONResponse($results);
-		} catch (\Exception $ex) {
+		} catch (\Exception) {
 			return new NotFoundResponse();
 		}
 	}
@@ -329,7 +325,7 @@ public function getPendingRequests() {
 	public function getRevisions($item_guid) {
 		try {
 			return new JSONResponse($this->shareService->getItemHistory($this->userId, $item_guid));
-		} catch (\Exception $ex) {
+		} catch (\Exception) {
 			return new NotFoundJSONResponse();
 		}
 	}
@@ -343,7 +339,7 @@ public function getRevisions($item_guid) {
 	public function getVaultItems($vault_guid) {
 		try {
 			return new JSONResponse($this->shareService->getSharedItems($this->userId->getUID(), $vault_guid));
-		} catch (\Exception $ex) {
+		} catch (\Exception) {
 			return new NotFoundResponse();
 		}
 	}
@@ -357,7 +353,7 @@ public function getVaultItems($vault_guid) {
 	public function getVaultAclEntries($vault_guid) {
 		try {
 			return new JSONResponse($this->shareService->getVaultAclList($this->userId->getUID(), $vault_guid));
-		} catch (\Exception $ex) {
+		} catch (\Exception) {
 			return new NotFoundResponse();
 		}
 	}
@@ -373,7 +369,7 @@ public function deleteShareRequest($share_request_id) {
 
 			$sr = $this->shareService->getShareRequestById($share_request_id);
 			$notification = [
-				'from_user' => ucfirst($this->userId->getDisplayName()),
+				'from_user' => ucfirst((string) $this->userId->getDisplayName()),
 				'credential_label' => $this->credentialService->getCredentialLabelById($sr->getItemId())->getLabel(),
 				'target_user' => $sr->getFromUserId(),
 				'req_id' => $sr->getId()
@@ -391,7 +387,7 @@ public function deleteShareRequest($share_request_id) {
 
 			$this->shareService->cleanItemRequestsForUser($sr);
 			return new JSONResponse(['result' => true]);
-		} catch (\Exception $ex) {
+		} catch (\Exception) {
 			return new NotFoundJSONResponse();
 		}
 	}
@@ -424,7 +420,7 @@ public function getPublicCredentialData($credential_guid) {
 		try {
 			$credential = $this->shareService->getSharedItem(null, $credential_guid);
 			return new JSONResponse($credential);
-		} catch (\Exception $ex) {
+		} catch (\Exception) {
 			return new NotFoundJSONResponse();
 		}
 	}
@@ -450,7 +446,7 @@ public function getItemAcl($item_guid) {
 			} else {
 				return new NotFoundResponse();
 			}
-		} catch (\Exception $ex) {
+		} catch (\Exception) {
 			return new JSONResponse([]);
 		}
 	}
@@ -467,7 +463,7 @@ public function getItemAcl($item_guid) {
 	public function getFile($item_guid, $file_guid) {
 		try {
 			$credential = $this->credentialService->getCredentialByGUID($item_guid);
-		} catch (\Exception $e) {
+		} catch (\Exception) {
 			return new NotFoundJSONResponse();
 		}
 
@@ -497,7 +493,7 @@ public function getFile($item_guid, $file_guid) {
 	public function uploadFile($item_guid, $data, $filename, $mimetype, $size) {
 		try {
 			$credential = $this->credentialService->getCredentialByGUID($item_guid);
-		} catch (\Exception $e) {
+		} catch (\Exception) {
 			return new NotFoundJSONResponse();
 		}
 
@@ -532,7 +528,7 @@ public function uploadFile($item_guid, $data, $filename, $mimetype, $size) {
 	public function updateSharedCredentialACL($item_guid, $user_id, $permission) {
 		try {
 			$credential = $this->credentialService->getCredentialByGUID($item_guid);
-		} catch (\Exception $exception) {
+		} catch (\Exception) {
 			return new NotFoundJSONResponse();
 		}
 		if ($this->userId->getUID() === $credential->getUserId()) {
@@ -541,7 +537,7 @@ public function updateSharedCredentialACL($item_guid, $user_id, $permission) {
 				$acl = $this->shareService->getACL($user_id, $item_guid);
 				$acl->setPermissions($permission);
 				return $this->shareService->updateCredentialACL($acl);
-			} catch (\Exception $exception) {
+			} catch (\Exception) {
 
 			}
 
diff --git a/lib/Controller/TranslationController.php b/lib/Controller/TranslationController.php
index 40533bd46..10d35d401 100644
--- a/lib/Controller/TranslationController.php
+++ b/lib/Controller/TranslationController.php
@@ -21,7 +21,7 @@ class TranslationController extends ApiController {
 	public function __construct(
 		$AppName,
 		IRequest $request,
-		private IL10N $trans,
+		private readonly IL10N $trans,
 	) {
 		parent::__construct(
 			$AppName,
diff --git a/lib/Controller/VaultController.php b/lib/Controller/VaultController.php
index f29e49149..23a9991b9 100644
--- a/lib/Controller/VaultController.php
+++ b/lib/Controller/VaultController.php
@@ -25,18 +25,16 @@
 
 
 class VaultController extends ApiController {
-	private $userId;
-
 	public function __construct(
 		$AppName,
 		IRequest $request,
-		$UserId,
-		private VaultService $vaultService,
-		private CredentialService $credentialService,
-		private DeleteVaultRequestService $deleteVaultRequestService,
-		private SettingsService $settings,
-		private FileService $fileService,
-		private LoggerInterface $logger,
+		private $userId,
+		private readonly VaultService $vaultService,
+		private readonly CredentialService $credentialService,
+		private readonly DeleteVaultRequestService $deleteVaultRequestService,
+		private readonly SettingsService $settings,
+		private readonly FileService $fileService,
+		private readonly LoggerInterface $logger,
 	) {
 		parent::__construct(
 			$AppName,
@@ -44,7 +42,6 @@ public function __construct(
 			'GET, POST, DELETE, PUT, PATCH, OPTIONS',
 			'Authorization, Content-Type, Accept',
 			86400);
-		$this->userId = $UserId;
 	}
 
 	/**
@@ -95,7 +92,7 @@ public function get($vault_guid) {
 		$vault = null;
 		try {
 			$vault = $this->vaultService->getByGuid($vault_guid, $this->userId);
-		} catch (\Exception $e) {
+		} catch (\Exception) {
 			return new NotFoundJSONResponse();
 		}
 		$result = [];
@@ -146,8 +143,8 @@ public function updateSharingKeys($vault_guid, $private_sharing_key, $public_sha
 		$vault = null;
 		try {
 			$vault = $this->vaultService->getByGuid($vault_guid, $this->userId);
-		} catch (\Exception $e) {
-			// No need to catch the execption
+		} catch (\Exception) {
+			// No need to catch the exception
 		}
 
 		if ($vault) {
@@ -181,7 +178,7 @@ public function delete($vault_guid) {
 					}
 				}
 			}
-		} catch (\Exception $e) {
+		} catch (\Exception) {
 			return new NotFoundJSONResponse();
 		}
 
diff --git a/lib/Db/CredentialMapper.php b/lib/Db/CredentialMapper.php
index 257874195..43a9100fb 100644
--- a/lib/Db/CredentialMapper.php
+++ b/lib/Db/CredentialMapper.php
@@ -25,18 +25,21 @@
 
 use OCA\Passman\Utility\Utils;
 use OCP\AppFramework\Db\DoesNotExistException;
-use OCP\AppFramework\Db\Entity;
 use OCP\AppFramework\Db\MultipleObjectsReturnedException;
 use OCP\AppFramework\Db\QBMapper;
+use OCP\DB\Exception;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\IDBConnection;
 
+/**
+ * @template-extends QBMapper<Credential>
+ */
 class CredentialMapper extends QBMapper {
 	const TABLE_NAME = 'passman_credentials';
 
 	public function __construct(
 		IDBConnection $db,
-		private Utils $utils,
+		private readonly Utils $utils,
 	) {
 		parent::__construct($db, self::TABLE_NAME);
 	}
@@ -47,9 +50,9 @@ public function __construct(
 	 *
 	 * @param string $vault_id
 	 * @param string $user_id
-	 * @return Entity[]
+	 * @return Credential[]
 	 */
-	public function getCredentialsByVaultId(string $vault_id, string $user_id) {
+	public function getCredentialsByVaultId(string $vault_id, string $user_id): array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -64,9 +67,10 @@ public function getCredentialsByVaultId(string $vault_id, string $user_id) {
 	 *
 	 * @param string $vault_id
 	 * @param string $user_id
-	 * @return Credential[]
+	 * @return Credential
+	 * @throws Exception
 	 */
-	public function getRandomCredentialByVaultId(string $vault_id, string $user_id) {
+	public function getRandomCredentialByVaultId(string $vault_id, string $user_id): Credential {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -76,20 +80,18 @@ public function getRandomCredentialByVaultId(string $vault_id, string $user_id)
 			->setMaxResults(20);
 
 		$entities = $this->findEntities($qb);
-		$count = count($entities) - 1;
+		$maxEntitiesIndex = count($entities) - 1;
 
-		/** @var Credential[] $entity */
-		$entity = array_splice($entities, rand(0, $count), 1);
-		return $entity;
+		return $entities[rand(0, $maxEntitiesIndex)];
 	}
 
 	/**
 	 * Get expired credentials
 	 *
 	 * @param int $timestamp
-	 * @return Entity[]
+	 * @return Credential[]
 	 */
-	public function getExpiredCredentials(int $timestamp) {
+	public function getExpiredCredentials(int $timestamp): array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -100,16 +102,16 @@ public function getExpiredCredentials(int $timestamp) {
 	}
 
 	/**
-	 * Get an credential by id.
+	 * Get a credential by id.
 	 * Optional user id
 	 *
 	 * @param int $credential_id
 	 * @param string|null $user_id
-	 * @return Entity
+	 * @return Credential
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getCredentialById(int $credential_id, string $user_id = null) {
+	public function getCredentialById(int $credential_id, ?string $user_id = null): Credential {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -126,11 +128,11 @@ public function getCredentialById(int $credential_id, string $user_id = null) {
 	 * Get credential label by id
 	 *
 	 * @param int $credential_id
-	 * @return Entity
+	 * @return Credential partial Credential, containing only 'id' and 'label'
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getCredentialLabelById(int $credential_id) {
+	public function getCredentialLabelById(int $credential_id): Credential {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select(['id', 'label'])
 			->from(self::TABLE_NAME)
@@ -145,7 +147,7 @@ public function getCredentialLabelById(int $credential_id) {
 	 * @param $raw_credential
 	 * @return Credential
 	 */
-	public function create($raw_credential) {
+	public function create($raw_credential): Credential {
 		$credential = new Credential();
 
 		$credential->setGuid($this->utils->GUID());
@@ -176,13 +178,13 @@ public function create($raw_credential) {
 	}
 
 	/**
-	 * @param $raw_credential array An array containing all the credential fields
-	 * @param $useRawUser bool
-	 * @return Credential|Entity The updated credential
+	 * @param array $raw_credential An array containing all the credential fields
+	 * @param bool $useRawUser
+	 * @return Credential The updated credential
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function updateCredential($raw_credential, bool $useRawUser) {
+	public function updateCredential(array $raw_credential, bool $useRawUser): Credential {
 		$original = $this->getCredentialByGUID($raw_credential['guid']);
 		$uid = ($useRawUser) ? $raw_credential['user_id'] : $original->getUserId();
 
@@ -216,11 +218,11 @@ public function updateCredential($raw_credential, bool $useRawUser) {
 		return parent::update($credential);
 	}
 
-	public function deleteCredential(Credential $credential) {
+	public function deleteCredential(Credential $credential): Credential {
 		return $this->delete($credential);
 	}
 
-	public function upd(Credential $credential) {
+	public function upd(Credential $credential): void {
 		$this->update($credential);
 	}
 
@@ -229,11 +231,11 @@ public function upd(Credential $credential) {
 	 *
 	 * @param string $credential_guid
 	 * @param string|null $user_id
-	 * @return Entity
+	 * @return Credential
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getCredentialByGUID(string $credential_guid, string $user_id = null) {
+	public function getCredentialByGUID(string $credential_guid, ?string $user_id = null): Credential {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
diff --git a/lib/Db/CredentialRevisionMapper.php b/lib/Db/CredentialRevisionMapper.php
index 001e43742..4550e6eda 100644
--- a/lib/Db/CredentialRevisionMapper.php
+++ b/lib/Db/CredentialRevisionMapper.php
@@ -25,19 +25,19 @@
 
 use OCA\Passman\Utility\Utils;
 use OCP\AppFramework\Db\DoesNotExistException;
-use OCP\AppFramework\Db\Entity;
 use OCP\AppFramework\Db\MultipleObjectsReturnedException;
 use OCP\AppFramework\Db\QBMapper;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\IDBConnection;
 
+/**
+ * @template-extends QBMapper<CredentialRevision>
+ */
 class CredentialRevisionMapper extends QBMapper {
 	const TABLE_NAME = 'passman_revisions';
-	private Utils $utils;
 
-	public function __construct(IDBConnection $db, Utils $utils) {
+	public function __construct(IDBConnection $db, private readonly Utils $utils) {
 		parent::__construct($db, self::TABLE_NAME);
-		$this->utils = $utils;
 	}
 
 
@@ -46,9 +46,9 @@ public function __construct(IDBConnection $db, Utils $utils) {
 	 *
 	 * @param int $credential_id
 	 * @param string|null $user_id
-	 * @return Entity[]
+	 * @return CredentialRevision[]
 	 */
-	public function getRevisions(int $credential_id, string $user_id = null) {
+	public function getRevisions(int $credential_id, ?string $user_id = null): array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -64,11 +64,11 @@ public function getRevisions(int $credential_id, string $user_id = null) {
 	/**
 	 * @param int $revision_id
 	 * @param string|null $user_id
-	 * @return Entity
+	 * @return CredentialRevision
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getRevision(int $revision_id, string $user_id = null) {
+	public function getRevision(int $revision_id, ?string $user_id = null): CredentialRevision {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -83,13 +83,13 @@ public function getRevision(int $revision_id, string $user_id = null) {
 
 	/**
 	 * Create a revision
-	 * @param $credential
-	 * @param $userId
-	 * @param $credential_id
-	 * @param $edited_by
+	 * @param mixed $credential
+	 * @param string $userId
+	 * @param int $credential_id
+	 * @param string $edited_by
 	 * @return CredentialRevision
 	 */
-	public function create($credential, $userId, $credential_id, $edited_by) {
+	public function create(mixed $credential, string $userId, int $credential_id, string $edited_by): CredentialRevision {
 		$revision = new CredentialRevision();
 		$revision->setGuid($this->utils->GUID());
 		$revision->setUserId($userId);
@@ -103,11 +103,11 @@ public function create($credential, $userId, $credential_id, $edited_by) {
 
 	/**
 	 * Delete a revision
-	 * @param $revision_id
-	 * @param $user_id
+	 * @param int $revision_id
+	 * @param string $user_id
 	 * @return CredentialRevision
 	 */
-	public function deleteRevision($revision_id, $user_id) {
+	public function deleteRevision(int $revision_id, string $user_id): CredentialRevision {
 		$revision = new CredentialRevision();
 		$revision->setId($revision_id);
 		$revision->setUserId($user_id);
diff --git a/lib/Db/DeleteVaultRequestMapper.php b/lib/Db/DeleteVaultRequestMapper.php
index 585780d4e..b863e751a 100644
--- a/lib/Db/DeleteVaultRequestMapper.php
+++ b/lib/Db/DeleteVaultRequestMapper.php
@@ -25,12 +25,14 @@
 
 
 use OCP\AppFramework\Db\DoesNotExistException;
-use OCP\AppFramework\Db\Entity;
 use OCP\AppFramework\Db\MultipleObjectsReturnedException;
 use OCP\AppFramework\Db\QBMapper;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\IDBConnection;
 
+/**
+ * @template-extends QBMapper<DeleteVaultRequest>
+ */
 class DeleteVaultRequestMapper extends QBMapper {
 	const TABLE_NAME = 'passman_delete_vault_request';
 
@@ -41,17 +43,17 @@ public function __construct(IDBConnection $db) {
 	/**
 	 * Create a new enty in the db
 	 * @param DeleteVaultRequest $request
-	 * @return Entity
+	 * @return DeleteVaultRequest
 	 */
-	public function createRequest(DeleteVaultRequest $request) {
+	public function createRequest(DeleteVaultRequest $request): DeleteVaultRequest {
 		return $this->insert($request);
 	}
 
 	/**
 	 * Get all delete requests
-	 * @return Entity[]
+	 * @return DeleteVaultRequest[]
 	 */
-	public function getDeleteRequests() {
+	public function getDeleteRequests(): array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME);
@@ -62,11 +64,11 @@ public function getDeleteRequests() {
 	/**
 	 * Get request for a vault guid
 	 * @param string $vault_guid
-	 * @return Entity
+	 * @return DeleteVaultRequest
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getDeleteRequestsForVault(string $vault_guid) {
+	public function getDeleteRequestsForVault(string $vault_guid): DeleteVaultRequest {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -80,8 +82,7 @@ public function getDeleteRequestsForVault(string $vault_guid) {
 	 * @param DeleteVaultRequest $request Request to delete
 	 * @return DeleteVaultRequest         The deleted request
 	 */
-	public function removeDeleteVaultRequest(DeleteVaultRequest $request) {
+	public function removeDeleteVaultRequest(DeleteVaultRequest $request): DeleteVaultRequest {
 		return $this->delete($request);
 	}
-
 }
diff --git a/lib/Db/FileMapper.php b/lib/Db/FileMapper.php
index 6e33a3edc..c0ca1353e 100644
--- a/lib/Db/FileMapper.php
+++ b/lib/Db/FileMapper.php
@@ -26,18 +26,20 @@
 
 use OCA\Passman\Utility\Utils;
 use OCP\AppFramework\Db\DoesNotExistException;
-use OCP\AppFramework\Db\Entity;
 use OCP\AppFramework\Db\MultipleObjectsReturnedException;
 use OCP\AppFramework\Db\QBMapper;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\IDBConnection;
 
+/**
+ * @template-extends QBMapper<File>
+ */
 class FileMapper extends QBMapper {
 	const TABLE_NAME = 'passman_files';
 
 	public function __construct(
 		IDBConnection $db,
-		private Utils $utils,
+		private readonly Utils $utils,
 	) {
 		parent::__construct($db, self::TABLE_NAME);
 	}
@@ -46,11 +48,11 @@ public function __construct(
 	/**
 	 * @param int $file_id
 	 * @param string|null $user_id
-	 * @return Entity
+	 * @return File
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getFile(int $file_id, string $user_id = null) {
+	public function getFile(int $file_id, ?string $user_id = null): File {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -66,11 +68,11 @@ public function getFile(int $file_id, string $user_id = null) {
 	/**
 	 * @param string $file_guid
 	 * @param string|null $user_id
-	 * @return Entity
+	 * @return File
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getFileByGuid(string $file_guid, string $user_id = null) {
+	public function getFileByGuid(string $file_guid, ?string $user_id = null): File {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -84,11 +86,11 @@ public function getFileByGuid(string $file_guid, string $user_id = null) {
 	}
 
 	/**
-	 * @param $file_raw
-	 * @param $userId
+	 * @param array|File $file_raw
+	 * @param string $userId
 	 * @return File
 	 */
-	public function create($file_raw, $userId) {
+	public function create(array|File $file_raw, string $userId): File {
 		$file = new File();
 		$file->setGuid($this->utils->GUID());
 		$file->setUserId($userId);
@@ -106,9 +108,9 @@ public function create($file_raw, $userId) {
 	 *
 	 * @param int $file_id
 	 * @param string $userId
-	 * @return File|Entity
+	 * @return File
 	 */
-	public function deleteFile(int $file_id, string $userId) {
+	public function deleteFile(int $file_id, string $userId): File {
 		$file = new File();
 		$file->setId($file_id);
 		$file->setUserId($userId);
@@ -116,19 +118,19 @@ public function deleteFile(int $file_id, string $userId) {
 	}
 
 	/**
-	 * Uodate file
+	 * Update file
 	 * @param File $file
 	 * @return File
 	 */
-	public function updateFile(File $file) {
+	public function updateFile(File $file): File {
 		return $this->update($file);
 	}
 
 	/**
 	 * @param string $user_id
-	 * @return Entity[]
+	 * @return File[] array of incomplete File objects, containing only the guid
 	 */
-	public function getFileGuidsFromUser(string $user_id) {
+	public function getFileGuidsFromUser(string $user_id): array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('guid')
 			->from(self::TABLE_NAME)
diff --git a/lib/Db/ShareRequestMapper.php b/lib/Db/ShareRequestMapper.php
index 3b12a3ba4..f6d088c30 100644
--- a/lib/Db/ShareRequestMapper.php
+++ b/lib/Db/ShareRequestMapper.php
@@ -25,14 +25,15 @@
 
 
 use OCP\AppFramework\Db\DoesNotExistException;
-use OCP\AppFramework\Db\Entity;
 use OCP\AppFramework\Db\MultipleObjectsReturnedException;
 use OCP\AppFramework\Db\QBMapper;
 use OCP\DB\Exception;
-use OCP\DB\IResult;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\IDBConnection;
 
+/**
+ * @template-extends QBMapper<ShareRequest>
+ */
 class ShareRequestMapper extends QBMapper {
 	const TABLE_NAME = 'passman_share_request';
 
@@ -42,9 +43,9 @@ public function __construct(IDBConnection $db) {
 
 	/**
 	 * @param ShareRequest $request
-	 * @return ShareRequest|Entity
+	 * @return ShareRequest
 	 */
-	public function createRequest(ShareRequest $request) {
+	public function createRequest(ShareRequest $request): ShareRequest {
 		return $this->insert($request);
 	}
 
@@ -53,11 +54,11 @@ public function createRequest(ShareRequest $request) {
 	 *
 	 * @param string $item_guid
 	 * @param string $target_vault_guid
-	 * @return Entity
+	 * @return ShareRequest
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getRequestByItemAndVaultGuid(string $item_guid, string $target_vault_guid) {
+	public function getRequestByItemAndVaultGuid(string $item_guid, string $target_vault_guid): ShareRequest {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -71,11 +72,11 @@ public function getRequestByItemAndVaultGuid(string $item_guid, string $target_v
 	 * Get shared items for the given item_guid
 	 *
 	 * @param string $item_guid
-	 * @return Entity[]
+	 * @return ShareRequest[]
 	 * @throws Exception
 	 */
-	public function getRequestsByItemGuid(string $item_guid) {
-		if (strtolower($this->db->getDatabasePlatform()->getName()) === 'mysql') {
+	public function getRequestsByItemGuid(string $item_guid): array {
+		if ($this->db->getDatabaseProvider() === IDBConnection::PLATFORM_MYSQL) {
 			$this->db->executeQuery("SET sql_mode = '';");
 		}
 		$qb = $this->db->getQueryBuilder();
@@ -91,10 +92,10 @@ public function getRequestsByItemGuid(string $item_guid) {
 	 *
 	 * @param int $item_id
 	 * @param string $target_user_id
-	 * @return int|IResult
+	 * @return int
 	 * @throws Exception
 	 */
-	public function cleanItemRequestsForUser(int $item_id, string $target_user_id) {
+	public function cleanItemRequestsForUser(int $item_id, string $target_user_id): int {
 		$qb = $this->db->getQueryBuilder();
 		return $qb->delete(self::TABLE_NAME)
 			->where($qb->expr()->eq('item_id', $qb->createNamedParameter($item_id, IQueryBuilder::PARAM_INT)))
@@ -106,9 +107,9 @@ public function cleanItemRequestsForUser(int $item_id, string $target_user_id) {
 	 * Obtains all pending share requests for the given user ID
 	 *
 	 * @param string $user_id
-	 * @return Entity[]
+	 * @return ShareRequest[]
 	 */
-	public function getUserPendingRequests(string $user_id) {
+	public function getUserPendingRequests(string $user_id): array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -122,19 +123,19 @@ public function getUserPendingRequests(string $user_id) {
 	 * @param ShareRequest $shareRequest Request to delete
 	 * @return ShareRequest                 The deleted request
 	 */
-	public function deleteShareRequest(ShareRequest $shareRequest) {
+	public function deleteShareRequest(ShareRequest $shareRequest): ShareRequest {
 		return $this->delete($shareRequest);
 	}
 
 	/**
-	 * Gets a share request by it's unique incremental id
+	 * Gets a share request by its unique incremental id
 	 *
 	 * @param int $id
-	 * @return Entity
+	 * @return ShareRequest
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getShareRequestById(int $id) {
+	public function getShareRequestById(int $id): ShareRequest {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -147,9 +148,9 @@ public function getShareRequestById(int $id) {
 	 * Gets all share requests by a given item GUID
 	 *
 	 * @param string $item_guid
-	 * @return Entity[]
+	 * @return ShareRequest[]
 	 */
-	public function getShareRequestsByItemGuid(string $item_guid) {
+	public function getShareRequestsByItemGuid(string $item_guid): array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -163,7 +164,7 @@ public function getShareRequestsByItemGuid(string $item_guid) {
 	 * @param ShareRequest $shareRequest
 	 * @return ShareRequest
 	 */
-	public function updateShareRequest(ShareRequest $shareRequest) {
+	public function updateShareRequest(ShareRequest $shareRequest): ShareRequest {
 		return $this->update($shareRequest);
 	}
 
@@ -172,9 +173,9 @@ public function updateShareRequest(ShareRequest $shareRequest) {
 	 *
 	 * @param string $item_guid
 	 * @param string $user_id
-	 * @return Entity[]
+	 * @return ShareRequest[]
 	 */
-	public function getPendingShareRequests(string $item_guid, string $user_id) {
+	public function getPendingShareRequests(string $item_guid, string $user_id): array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -190,10 +191,10 @@ public function getPendingShareRequests(string $item_guid, string $user_id) {
 	 * @param string $item_guid The item for which to update the requests
 	 * @param string $user_id The user for which to update the requests
 	 * @param int $permissions The new permissions to apply
-	 * @return int|IResult
+	 * @return int
 	 * @throws Exception
 	 */
-	public function updatePendingRequestPermissions(string $item_guid, string $user_id, int $permissions) {
+	public function updatePendingRequestPermissions(string $item_guid, string $user_id, int $permissions): int {
 		$qb = $this->db->getQueryBuilder();
 		return $qb->update(self::TABLE_NAME)
 			->set('permissions', $qb->createNamedParameter($permissions, IQueryBuilder::PARAM_INT))
diff --git a/lib/Db/SharingACLMapper.php b/lib/Db/SharingACLMapper.php
index cf525efaf..28bcd8103 100644
--- a/lib/Db/SharingACLMapper.php
+++ b/lib/Db/SharingACLMapper.php
@@ -25,12 +25,14 @@
 
 
 use OCP\AppFramework\Db\DoesNotExistException;
-use OCP\AppFramework\Db\Entity;
 use OCP\AppFramework\Db\MultipleObjectsReturnedException;
 use OCP\AppFramework\Db\QBMapper;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\IDBConnection;
 
+/**
+ * @template-extends QBMapper<SharingACL>
+ */
 class SharingACLMapper extends QBMapper {
 	const TABLE_NAME = 'passman_sharing_acl';
 
@@ -39,11 +41,11 @@ public function __construct(IDBConnection $db) {
 	}
 
 	/**
-	 * @param SharingACL $acl
-	 * @return SharingACL|Entity
+	 * @param SharingACL $sharingACL
+	 * @return SharingACL
 	 */
-	public function createACLEntry(SharingACL $acl) {
-		return $this->insert($acl);
+	public function createACLEntry(SharingACL $sharingACL): SharingACL {
+		return $this->insert($sharingACL);
 	}
 
 	/**
@@ -51,9 +53,9 @@ public function createACLEntry(SharingACL $acl) {
 	 *
 	 * @param string $user_id
 	 * @param string $vault_guid
-	 * @return Entity[]
+	 * @return SharingACL[]
 	 */
-	public function getVaultEntries(string $user_id, string $vault_guid) {
+	public function getVaultEntries(string $user_id, string $vault_guid): array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -66,13 +68,13 @@ public function getVaultEntries(string $user_id, string $vault_guid) {
 	/**
 	 * Gets the acl for a given item guid
 	 *
-	 * @param string $user_id
+	 * @param string|null $user_id
 	 * @param string $item_guid
-	 * @return Entity
+	 * @return SharingACL
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getItemACL(?string $user_id, string $item_guid) {
+	public function getItemACL(?string $user_id, string $item_guid): SharingACL {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -91,9 +93,9 @@ public function getItemACL(?string $user_id, string $item_guid) {
 	 * Update an acl
 	 *
 	 * @param SharingACL $sharingACL
-	 * @return SharingACL|Entity
+	 * @return SharingACL
 	 */
-	public function updateCredentialACL(SharingACL $sharingACL) {
+	public function updateCredentialACL(SharingACL $sharingACL): SharingACL {
 		return $this->update($sharingACL);
 	}
 
@@ -101,9 +103,9 @@ public function updateCredentialACL(SharingACL $sharingACL) {
 	 * Gets the currently accepted share requests from the given user for the given vault guid
 	 *
 	 * @param string $item_guid
-	 * @return Entity[]
+	 * @return SharingACL[]
 	 */
-	public function getCredentialAclList(string $item_guid) {
+	public function getCredentialAclList(string $item_guid): array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -113,10 +115,10 @@ public function getCredentialAclList(string $item_guid) {
 	}
 
 	/**
-	 * @param SharingACL $ACL
-	 * @return SharingACL|Entity
+	 * @param SharingACL $sharingACL
+	 * @return SharingACL
 	 */
-	public function deleteShareACL(SharingACL $ACL) {
-		return $this->delete($ACL);
+	public function deleteShareACL(SharingACL $sharingACL): SharingACL {
+		return $this->delete($sharingACL);
 	}
 }
diff --git a/lib/Db/VaultMapper.php b/lib/Db/VaultMapper.php
index e35356d41..2f822dc3b 100644
--- a/lib/Db/VaultMapper.php
+++ b/lib/Db/VaultMapper.php
@@ -25,18 +25,20 @@
 
 use OCA\Passman\Utility\Utils;
 use OCP\AppFramework\Db\DoesNotExistException;
-use OCP\AppFramework\Db\Entity;
 use OCP\AppFramework\Db\MultipleObjectsReturnedException;
 use OCP\AppFramework\Db\QBMapper;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\IDBConnection;
 
+/**
+ * @template-extends QBMapper<Vault>
+ */
 class VaultMapper extends QBMapper {
 	const TABLE_NAME = 'passman_vaults';
 
 	public function __construct(
 		IDBConnection $db,
-		private Utils $utils,
+		private readonly Utils $utils,
 	) {
 		parent::__construct($db, self::TABLE_NAME);
 	}
@@ -45,26 +47,26 @@ public function __construct(
 	/**
 	 * @param int $vault_id
 	 * @param string $user_id
-	 * @return Entity[]
+	 * @return Vault
 	 */
-	public function find(int $vault_id, string $user_id) {
+	public function findById(int $vault_id, string $user_id): Vault {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
 			->where($qb->expr()->eq('id', $qb->createNamedParameter($vault_id, IQueryBuilder::PARAM_INT)))
 			->andWhere($qb->expr()->eq('user_id', $qb->createNamedParameter($user_id, IQueryBuilder::PARAM_STR)));
 
-		return $this->findEntities($qb);
+		return $this->findEntity($qb);
 	}
 
 	/**
 	 * @param string $vault_guid
 	 * @param string $user_id
-	 * @return Entity
+	 * @return Vault
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function findByGuid(string $vault_guid, string $user_id) {
+	public function findByGuid(string $vault_guid, string $user_id): Vault {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -77,9 +79,9 @@ public function findByGuid(string $vault_guid, string $user_id) {
 
 	/**
 	 * @param string $user_id
-	 * @return Entity[]
+	 * @return Vault[]
 	 */
-	public function findVaultsFromUser(string $user_id) {
+	public function findVaultsFromUser(string $user_id): array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from(self::TABLE_NAME)
@@ -93,9 +95,9 @@ public function findVaultsFromUser(string $user_id) {
 	 *
 	 * @param string $vault_name
 	 * @param string $user_id
-	 * @return Vault|Entity
+	 * @return Vault
 	 */
-	public function create(string $vault_name, string $user_id) {
+	public function create(string $vault_name, string $user_id): Vault {
 		$vault = new Vault();
 		$vault->setName($vault_name);
 		$vault->setUserId($user_id);
@@ -110,9 +112,9 @@ public function create(string $vault_name, string $user_id) {
 	 *
 	 * @param int $vault_id
 	 * @param string $user_id
-	 * @return Vault|Entity
+	 * @return Vault
 	 */
-	public function setLastAccess(int $vault_id, string $user_id) {
+	public function setLastAccess(int $vault_id, string $user_id): Vault {
 		$vault = new Vault();
 		$vault->setId($vault_id);
 		$vault->setUserId($user_id);
@@ -124,9 +126,9 @@ public function setLastAccess(int $vault_id, string $user_id) {
 	 * Update vault
 	 *
 	 * @param Vault $vault
-	 * @return Vault|Entity
+	 * @return Vault
 	 */
-	public function updateVault(Vault $vault) {
+	public function updateVault(Vault $vault): Vault {
 		return $this->update($vault);
 	}
 
@@ -136,9 +138,9 @@ public function updateVault(Vault $vault) {
 	 * @param int $vault_id
 	 * @param string $privateKey
 	 * @param string $publicKey
-	 * @return Vault|Entity
+	 * @return Vault
 	 */
-	public function updateSharingKeys(int $vault_id, string $privateKey, string $publicKey) {
+	public function updateSharingKeys(int $vault_id, string $privateKey, string $publicKey): Vault {
 		$vault = new Vault();
 		$vault->setId($vault_id);
 		$vault->setPrivateSharingKey($privateKey);
@@ -152,7 +154,7 @@ public function updateSharingKeys(int $vault_id, string $privateKey, string $pub
 	 *
 	 * @param Vault $vault
 	 */
-	public function deleteVault(Vault $vault) {
+	public function deleteVault(Vault $vault): void {
 		$this->delete($vault);
 	}
 }
diff --git a/lib/Middleware/APIMiddleware.php b/lib/Middleware/APIMiddleware.php
index 92f3cc176..21c076df1 100644
--- a/lib/Middleware/APIMiddleware.php
+++ b/lib/Middleware/APIMiddleware.php
@@ -10,7 +10,7 @@
 class APIMiddleware extends Middleware {
 
 	public function __construct(
-		private IRequest $request,
+		private readonly IRequest $request,
 	) {
 	}
 
diff --git a/lib/Middleware/ShareMiddleware.php b/lib/Middleware/ShareMiddleware.php
index 75aa138f0..699e83928 100644
--- a/lib/Middleware/ShareMiddleware.php
+++ b/lib/Middleware/ShareMiddleware.php
@@ -10,11 +10,9 @@
 
 class ShareMiddleware extends Middleware {
 
-	private $settings;
-
-	public function __construct(SettingsService $config) {
-		$this->settings = $config;
-	}
+	public function __construct(private readonly SettingsService $settings)
+    {
+    }
 
 
 	public function beforeController($controller, $methodName) {
diff --git a/lib/Migration/ServerSideEncryption.php b/lib/Migration/ServerSideEncryption.php
index 3726ec3f8..414b01ad9 100644
--- a/lib/Migration/ServerSideEncryption.php
+++ b/lib/Migration/ServerSideEncryption.php
@@ -43,12 +43,12 @@ class ServerSideEncryption implements IRepairStep {
 	private $installedVersion;
 
 	public function __construct(
-		private EncryptService $encryptService,
-		private IDBConnection $db,
-		private LoggerInterface $logger,
-		private CredentialService $credentialService,
-		private CredentialRevisionService $revisionService,
-		private FileService $fileService,
+		private readonly EncryptService $encryptService,
+		private readonly IDBConnection $db,
+		private readonly LoggerInterface $logger,
+		private readonly CredentialService $credentialService,
+		private readonly CredentialRevisionService $revisionService,
+		private readonly FileService $fileService,
 		IConfig $config,
 	) {
 		$this->installedVersion = $config->getAppValue('passman', 'installed_version');
diff --git a/lib/Search/Provider.php b/lib/Search/Provider.php
index cac452e32..8385fd05e 100644
--- a/lib/Search/Provider.php
+++ b/lib/Search/Provider.php
@@ -43,10 +43,10 @@
 class Provider implements IProvider {
 
 	public function __construct(
-		private IL10N $l10n,
-		private IURLGenerator $urlGenerator,
-		private IDBConnection $db,
-		private SettingsService $settings,
+		private readonly IL10N $l10n,
+		private readonly IURLGenerator $urlGenerator,
+		private readonly IDBConnection $db,
+		private readonly SettingsService $settings,
 	) {
 
 	}
@@ -60,7 +60,7 @@ public function getName(): string {
 	}
 
 	public function getOrder(string $route, array $routeParameters): int {
-		if (strpos($route, Application::APP_ID . '.') === 0) {
+		if (str_starts_with($route, Application::APP_ID . '.')) {
 			// Active app, prefer my results
 			return -1;
 		}
@@ -72,29 +72,28 @@ public function search(IUser $user, ISearchQuery $query): SearchResult {
 		$searchResultEntries = [];
 
 		if ($this->settings->getAppSetting('enable_global_search', 0) === 1) {
-			$VaultService = new VaultService(new VaultMapper($this->db, new Utils()));
-			$Vaults = $VaultService->getByUser($user->getUID());
-			$CredentialMapper = new CredentialMapper($this->db, new Utils());
+			$vaultService = new VaultService(new VaultMapper($this->db, new Utils()));
+			$vaults = $vaultService->getByUser($user->getUID());
+			$credentialMapper = new CredentialMapper($this->db, new Utils());
 
-			foreach ($Vaults as $Vault) {
+			foreach ($vaults as $vault) {
 				try {
-					$Credentials = $CredentialMapper->getCredentialsByVaultId($Vault->getId(), $Vault->getUserId());
+					$credentials = $credentialMapper->getCredentialsByVaultId($vault->getId(), $vault->getUserId());
 
-					foreach ($Credentials as $Credential) {
-						if (strpos($Credential->getLabel(), $query->getTerm()) !== false) {
+					foreach ($credentials as $credential) {
+						if (str_contains($credential->getLabel(), $query->getTerm())) {
 							try {
 								$searchResultEntries[] = new SearchResultEntry(
 									$this->urlGenerator->imagePath(Application::APP_ID, 'app.svg'),
-									$Credential->getLabel(),
-									\sprintf("Part of Passman vault %s", $Vault->getName()),
-									$this->urlGenerator->linkToRoute('passman.Page.index') . "#/vault/" . $Vault->getGuid() . "?show=" . $Credential->getGuid()
+									$credential->getLabel(),
+									\sprintf("Part of Passman vault %s", $vault->getName()),
+									$this->urlGenerator->linkToRoute('passman.Page.index') . "#/vault/" . $vault->getGuid() . "?show=" . $credential->getGuid()
 								);
-							} catch (\Exception $e) {
+							} catch (\Exception) {
 							}
 						}
 					}
-				} catch (DoesNotExistException $e) {
-				} catch (MultipleObjectsReturnedException $e) {
+				} catch (DoesNotExistException|MultipleObjectsReturnedException) {
 				}
 			}
 		}
diff --git a/lib/Service/CredentialRevisionService.php b/lib/Service/CredentialRevisionService.php
index 83072bb6e..45453f447 100644
--- a/lib/Service/CredentialRevisionService.php
+++ b/lib/Service/CredentialRevisionService.php
@@ -26,7 +26,6 @@
 use OCA\Passman\Db\CredentialRevision;
 use OCA\Passman\Db\CredentialRevisionMapper;
 use OCP\AppFramework\Db\DoesNotExistException;
-use OCP\AppFramework\Db\Entity;
 use OCP\AppFramework\Db\MultipleObjectsReturnedException;
 use OCP\IConfig;
 
@@ -36,8 +35,8 @@ class CredentialRevisionService {
 	private $server_key;
 
 	public function __construct(
-		private CredentialRevisionMapper $credentialRevisionMapper,
-		private EncryptService $encryptService,
+		private readonly CredentialRevisionMapper $credentialRevisionMapper,
+		private readonly EncryptService $encryptService,
 		IConfig $config,
 	) {
 		$this->server_key = $config->getSystemValue('passwordsalt', '');
@@ -53,7 +52,7 @@ public function __construct(
 	 * @return CredentialRevision
 	 * @throws \Exception
 	 */
-	public function createRevision($credential, $userId, $credential_id, $edited_by) {
+	public function createRevision($credential, $userId, $credential_id, $edited_by): CredentialRevision {
 		$credential = $this->encryptService->encryptCredential($credential);
 		return $this->credentialRevisionMapper->create($credential, $userId, $credential_id, $edited_by);
 	}
@@ -63,15 +62,17 @@ public function createRevision($credential, $userId, $credential_id, $edited_by)
 	 *
 	 * @param int $credential_id
 	 * @param string|null $user_id
-	 * @return Entity[]
+	 * @return CredentialRevision[] array with the json optimized ("serialized") versions of CredentialRevision
 	 * @throws \Exception
 	 */
-	public function getRevisions(int $credential_id, string $user_id = null) {
-		$result = $this->credentialRevisionMapper->getRevisions($credential_id, $user_id);
-		foreach ($result as $index => $revision) {
+	public function getRevisions(int $credential_id, ?string $user_id = null): array {
+		$result = [];
+		$revisions = $this->credentialRevisionMapper->getRevisions($credential_id, $user_id);
+		foreach ($revisions as $revision) {
 			$c = json_decode(base64_decode($revision->getCredentialData()), true);
-			$result[$index] = $revision->jsonSerialize();
-			$result[$index]['credential_data'] = $this->encryptService->decryptCredential($c);
+			$serializedRevision = $revision->jsonSerialize();
+			$serializedRevision['credential_data'] = $this->encryptService->decryptCredential($c);
+			$result[] = $serializedRevision;
 		}
 		return $result;
 	}
@@ -79,12 +80,12 @@ public function getRevisions(int $credential_id, string $user_id = null) {
 	/**
 	 * @param int $credential_id
 	 * @param string|null $user_id
-	 * @return Entity
+	 * @return CredentialRevision
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 * @throws \Exception
 	 */
-	public function getRevision(int $credential_id, string $user_id = null) {
+	public function getRevision(int $credential_id, ?string $user_id = null): CredentialRevision {
 		$revision = $this->credentialRevisionMapper->getRevision($credential_id, $user_id);
 		$c = json_decode(base64_decode($revision->getCredentialData()), true);
 		$revision->setCredentialData($this->encryptService->decryptCredential($c));
@@ -98,7 +99,7 @@ public function getRevision(int $credential_id, string $user_id = null) {
 	 * @param string $user_id
 	 * @return CredentialRevision
 	 */
-	public function deleteRevision(int $revision_id, string $user_id) {
+	public function deleteRevision(int $revision_id, string $user_id): CredentialRevision {
 		return $this->credentialRevisionMapper->deleteRevision($revision_id, $user_id);
 	}
 
@@ -106,10 +107,10 @@ public function deleteRevision(int $revision_id, string $user_id) {
 	 * Update revision
 	 *
 	 * @param CredentialRevision $credentialRevision
-	 * @return CredentialRevision|Entity
+	 * @return CredentialRevision
 	 * @throws \Exception
 	 */
-	public function updateRevision(CredentialRevision $credentialRevision) {
+	public function updateRevision(CredentialRevision $credentialRevision): CredentialRevision {
 		$credential_data = $credentialRevision->getCredentialData();
 		$credential_data = json_decode(base64_decode($credential_data), true);
 		$credential_data = base64_encode(json_encode($this->encryptService->encryptCredential($credential_data)));
diff --git a/lib/Service/CredentialService.php b/lib/Service/CredentialService.php
index fe66949e6..700048d7d 100644
--- a/lib/Service/CredentialService.php
+++ b/lib/Service/CredentialService.php
@@ -29,8 +29,8 @@
 use OCA\Passman\Db\SharingACL;
 use OCA\Passman\Db\SharingACLMapper;
 use OCP\AppFramework\Db\DoesNotExistException;
-use OCP\AppFramework\Db\Entity;
 use OCP\AppFramework\Db\MultipleObjectsReturnedException;
+use OCP\DB\Exception;
 use OCP\IConfig;
 use OCP\IURLGenerator;
 
@@ -40,15 +40,15 @@ class CredentialService {
 	private $server_key;
 
 	public function __construct(
-		private CredentialMapper          $credentialMapper,
-		private SharingACLMapper          $sharingACL,
-		private ActivityService           $activityService,
-		private ShareService              $shareService,
-		private EncryptService            $encryptService,
-		private CredentialRevisionService $credentialRevisionService,
-		private IURLGenerator             $urlGenerator,
-		private VaultService              $vaultService,
-		private NotificationService       $notificationService,
+		private readonly CredentialMapper          $credentialMapper,
+		private readonly SharingACLMapper          $sharingACL,
+		private readonly ActivityService           $activityService,
+		private readonly ShareService              $shareService,
+		private readonly EncryptService            $encryptService,
+		private readonly CredentialRevisionService $credentialRevisionService,
+		private readonly IURLGenerator             $urlGenerator,
+		private readonly VaultService              $vaultService,
+		private readonly NotificationService       $notificationService,
 		IConfig                           $config,
 	) {
 		$this->server_key = $config->getSystemValue('passwordsalt', '');
@@ -61,7 +61,7 @@ public function __construct(
 	 * @return Credential
 	 * @throws \Exception
 	 */
-	public function createCredential(array $credential) {
+	public function createCredential(array $credential): Credential {
 		$credential = $this->encryptService->encryptCredential($credential);
 		return $this->credentialMapper->create($credential);
 	}
@@ -70,25 +70,26 @@ public function createCredential(array $credential) {
 	 * Update credential
 	 *
 	 * @param array $credential
-	 * @param false $useRawUser
-	 * @return Credential|Entity
+	 * @param bool $useRawUser
+	 * @return Credential
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function updateCredential(array $credential, $useRawUser = false) {
-		$credential = $this->encryptService->encryptCredential($credential);
-		return $this->credentialMapper->updateCredential($credential, $useRawUser);
+	public function updateCredential(array $credential, bool $useRawUser = false): Credential {
+		$encryptedCredentialData = $this->encryptService->encryptCredential($credential);
+		return $this->credentialMapper->updateCredential((array) $encryptedCredentialData, $useRawUser);
 	}
 
 	/**
-	 * Update credential
+	 * Update credential based on its model/entity.
+	 * Usually only for internal processing.
 	 *
 	 * @param Credential $credential
-	 * @return Credential|Entity
+	 * @return Credential
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function upd(Credential $credential) {
+	public function updateCredentialEntity(Credential $credential): Credential {
 		$credential = $this->encryptService->encryptCredential($credential);
 		return $this->credentialMapper->updateCredential($credential->jsonSerialize(), false);
 	}
@@ -97,19 +98,21 @@ public function upd(Credential $credential) {
 	 * Delete credential
 	 *
 	 * @param Credential $credential
-	 * @return Entity
+	 * @return Credential
 	 */
-	public function deleteCredential(Credential $credential) {
+	public function deleteCredential(Credential $credential): Credential {
 		$this->shareService->unshareCredential($credential->getGuid());
 		return $this->credentialMapper->deleteCredential($credential);
 	}
 
 	/**
 	 * Delete leftovers from a credential
+	 *
 	 * @param Credential $credential
+	 * @param string $userId
 	 * @throws \Exception
 	 */
-	public function deleteCredentialParts(Credential $credential, $userId) {
+	public function deleteCredentialParts(Credential $credential, string $userId): void {
 		$this->activityService->add(
 			'item_destroyed_self', [$credential->getLabel()],
 			'', [],
@@ -129,10 +132,10 @@ public function deleteCredentialParts(Credential $credential, $userId) {
 	 *
 	 * @param int $vault_id
 	 * @param string $user_id
-	 * @return Entity[]
+	 * @return Credential[]
 	 * @throws \Exception
 	 */
-	public function getCredentialsByVaultId(int $vault_id, string $user_id) {
+	public function getCredentialsByVaultId(int $vault_id, string $user_id): array {
 		$credentials = $this->credentialMapper->getCredentialsByVaultId($vault_id, $user_id);
 		foreach ($credentials as $index => $credential) {
 			$credentials[$index] = $this->encryptService->decryptCredential($credential);
@@ -145,24 +148,22 @@ public function getCredentialsByVaultId(int $vault_id, string $user_id) {
 	 *
 	 * @param int $vault_id
 	 * @param string $user_id
-	 * @return mixed
+	 * @return Credential
+	 * @throws Exception
 	 */
-	public function getRandomCredentialByVaultId(int $vault_id, string $user_id) {
-		$credentials = $this->credentialMapper->getRandomCredentialByVaultId($vault_id, $user_id);
-		foreach ($credentials as $index => $credential) {
-			$credentials[$index] = $this->encryptService->decryptCredential($credential);
-		}
-		return array_pop($credentials);
+	public function getRandomCredentialByVaultId(int $vault_id, string $user_id): Credential {
+		$credential = $this->credentialMapper->getRandomCredentialByVaultId($vault_id, $user_id);
+		return $this->encryptService->decryptCredential($credential);
 	}
 
 	/**
 	 * Get expired credentials.
 	 *
 	 * @param int $timestamp
-	 * @return Entity[]
+	 * @return Credential[]
 	 * @throws \Exception
 	 */
-	public function getExpiredCredentials(int $timestamp) {
+	public function getExpiredCredentials(int $timestamp): array {
 		$credentials = $this->credentialMapper->getExpiredCredentials($timestamp);
 		foreach ($credentials as $index => $credential) {
 			$credentials[$index] = $this->encryptService->decryptCredential($credential);
@@ -174,12 +175,12 @@ public function getExpiredCredentials(int $timestamp) {
 	 * Get a single credential.
 	 *
 	 * @param int $credential_id
-	 * @param string $user_id
-	 * @return array|Credential
+	 * @param string|null $user_id
+	 * @return Credential
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getCredentialById(int $credential_id, ?string $user_id) {
+	public function getCredentialById(int $credential_id, ?string $user_id): Credential {
 		$credential = $this->credentialMapper->getCredentialById($credential_id);
 		if ($credential->getUserId() === $user_id) {
 			return $this->encryptService->decryptCredential($credential);
@@ -209,13 +210,13 @@ public function credentialExistsById(int $credential_id): bool {
 	 * Get credential label by credential id.
 	 *
 	 * @param int $credential_id
-	 * @return array|Credential
+	 * @return Credential partial Credential, containing only 'id' and 'label'
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getCredentialLabelById(int $credential_id) {
-		$credential = $this->credentialMapper->getCredentialLabelById($credential_id);
-		return $this->encryptService->decryptCredential($credential);
+	public function getCredentialLabelById(int $credential_id): Credential {
+		$partialCredential = $this->credentialMapper->getCredentialLabelById($credential_id);
+		return $this->encryptService->decryptCredential($partialCredential);
 	}
 
 	/**
@@ -223,21 +224,21 @@ public function getCredentialLabelById(int $credential_id) {
 	 *
 	 * @param string $credential_guid
 	 * @param string|null $user_id
-	 * @return array|Credential
+	 * @return Credential
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getCredentialByGUID(string $credential_guid, string $user_id = null) {
+	public function getCredentialByGUID(string $credential_guid, ?string $user_id = null): Credential {
 		$credential = $this->credentialMapper->getCredentialByGUID($credential_guid, $user_id);
 		return $this->encryptService->decryptCredential($credential);
 	}
 
 	public function getDirectEditLink(Credential $credential): string {
-		$vaults = $this->vaultService->getById($credential->getVaultId(), $credential->getUserId());
+		$vault = $this->vaultService->getById($credential->getVaultId(), $credential->getUserId());
 		return $this->urlGenerator->getAbsoluteURL(
 			$this->urlGenerator->linkTo(
 				'',
-				'index.php/apps/passman/#/vault/' . $vaults[0]->getGuid() . '/edit/' . $credential->getGuid()
+				'index.php/apps/passman/#/vault/' . $vault->getGuid() . '/edit/' . $credential->getGuid()
 			)
 		);
 	}
diff --git a/lib/Service/CronService.php b/lib/Service/CronService.php
index de39670df..c68b62642 100644
--- a/lib/Service/CronService.php
+++ b/lib/Service/CronService.php
@@ -32,11 +32,11 @@
 class CronService {
 
 	public function __construct(
-		private CredentialService   $credentialService,
-		private LoggerInterface     $logger,
-		private Utils               $utils,
-		private NotificationService $notificationService,
-		private ActivityService     $activityService,
+		private readonly CredentialService   $credentialService,
+		private readonly LoggerInterface     $logger,
+		private readonly Utils               $utils,
+		private readonly NotificationService $notificationService,
+		private readonly ActivityService     $activityService,
 	) {
 	}
 
diff --git a/lib/Service/DeleteVaultRequestService.php b/lib/Service/DeleteVaultRequestService.php
index 2e98c6f06..0df2be102 100644
--- a/lib/Service/DeleteVaultRequestService.php
+++ b/lib/Service/DeleteVaultRequestService.php
@@ -25,55 +25,54 @@
 
 use OCA\Passman\Db\DeleteVaultRequest;
 use OCA\Passman\Db\DeleteVaultRequestMapper;
-use OCP\AppFramework\Db\Entity;
 
 
 class DeleteVaultRequestService {
 
 	public function __construct(
-		private DeleteVaultRequestMapper $deleteVaultRequestMapper,
+		private readonly DeleteVaultRequestMapper $deleteVaultRequestMapper,
 	) {
 	}
 
 	/**
-	 *  Create a new DeleteVaultRequest
+	 * Create a new DeleteVaultRequest
 	 *
 	 * @param $request DeleteVaultRequest
 	 * @return DeleteVaultRequest
 	 */
-	public function createRequest(DeleteVaultRequest $request) {
+	public function createRequest(DeleteVaultRequest $request): DeleteVaultRequest {
 		return $this->deleteVaultRequestMapper->insert($request);
 	}
 
 	/**
-	 * Create a new DeleteVaultRequest
+	 * Get all delete requests
 	 *
-	 * @return Entity[]
+	 * @return DeleteVaultRequest[]
 	 */
-	public function getDeleteRequests() {
+	public function getDeleteRequests(): array {
 		return $this->deleteVaultRequestMapper->getDeleteRequests();
 	}
 
 	/**
-	 *  Create a new DeleteVaultRequest
+	 * Get DeleteVaultRequest for a specific vault by its guid
 	 *
 	 * @param $vault_guid string The vault guid
-	 * @return bool | Entity
+	 * @return bool | DeleteVaultRequest
 	 */
-	public function getDeleteRequestForVault(string $vault_guid) {
+	public function getDeleteRequestForVault(string $vault_guid): DeleteVaultRequest|bool {
 		try {
 			return $this->deleteVaultRequestMapper->getDeleteRequestsForVault($vault_guid);
-		} catch (\Exception $e) {
+		} catch (\Exception) {
 			return false;
 		}
 	}
 
 	/**
-	 *  Create a new DeleteVaultRequest
+	 *  Deletes the given DeleteVaultRequest
 	 *
 	 * @param $req DeleteVaultRequest
 	 */
-	public function removeDeleteRequestForVault(DeleteVaultRequest $req) {
+	public function removeDeleteRequestForVault(DeleteVaultRequest $req): void {
 		$this->deleteVaultRequestMapper->removeDeleteVaultRequest($req);
 	}
 }
diff --git a/lib/Service/EncryptService.php b/lib/Service/EncryptService.php
index 82fb46328..3110c87e9 100644
--- a/lib/Service/EncryptService.php
+++ b/lib/Service/EncryptService.php
@@ -28,7 +28,6 @@
 // Upgraded to use openssl
 use OCA\Passman\Db\Credential;
 use OCA\Passman\Db\File;
-use OCP\AppFramework\Db\Entity;
 use OCP\IConfig;
 
 /**
@@ -68,7 +67,16 @@ class EncryptService {
 
 	// The fields of a credential which are encrypted
 	public $encrypted_credential_fields = [
-		'description', 'username', 'password', 'files', 'custom_fields', 'otp', 'email', 'tags', 'url', 'icon'
+		'description',
+		'username',
+		'password',
+		'files',
+		'custom_fields',
+		'otp',
+		'email',
+		'tags',
+		'url',
+		'icon'
 	];
 
 	// Contains the server key
@@ -124,16 +132,15 @@ public function getKeySize() {
 	/**
 	 * Decrypt the data with the provided key
 	 *
-	 * @param string $data_hex The encrypted datat to decrypt
+	 * @param string|null $data_hex The encrypted data to decrypt. Accept null for dynamic caller compatibility, but always return false then.
 	 * @param string $key The key to use for decryption
 	 *
 	 * @returns string|false The returned string if decryption is successful
 	 *                           false if it is not
 	 */
-	public function decrypt($data_hex, $key) {
-
+	public function decrypt(?string $data_hex, string $key): bool|string {
 		if (!function_exists('hex2bin')) {
-			function hex2bin($str) {
+			function hex2bin(string $str): string {
 				$sbin = "";
 				$len = strlen($str);
 				for ($i = 0; $i < $len; $i += 2) {
@@ -143,6 +150,9 @@ function hex2bin($str) {
 				return $sbin;
 			}
 		}
+		if ($data_hex === null) {
+			return false;
+		}
 
 		$data = hex2bin($data_hex);
 
@@ -150,13 +160,11 @@ function hex2bin($str) {
 		$enc = substr($data, 128, -64);
 		$mac = substr($data, -64);
 
-		list ($cipherKey, $macKey, $iv) = $this->getKeys($salt, $key);
+		[$cipherKey, $macKey, $iv] = $this->getKeys($salt, $key);
 
-		if (hash_equals(hash_hmac('sha512', $enc, $macKey, true), $mac)) {
+		if (hash_equals(hash_hmac('sha512', $enc, (string)$macKey, true), $mac)) {
 			$dec = openssl_decrypt($enc, $this->cipher, $cipherKey, true, $iv);
-			$data = $this->unpad($dec);
-
-			return $data;
+			return $this->unpad($dec);
 		}
 
 		return false;
@@ -170,19 +178,17 @@ function hex2bin($str) {
 	 *
 	 * @returns string The encrypted data
 	 */
-	public function encrypt($data, $key) {
+	public function encrypt(string $data, string $key): string {
 		if (function_exists('random_bytes')) {
 			$salt = random_bytes(128);
 		} else {
 			$salt = openssl_random_pseudo_bytes(128);
 		}
-		list ($cipherKey, $macKey, $iv) = $this->getKeys($salt, $key);
+		[$cipherKey, $macKey, $iv] = $this->getKeys($salt, $key);
 		$data = $this->pad($data);
 		$enc = openssl_encrypt($data, $this->cipher, $cipherKey, true, $iv);
-		$mac = hash_hmac('sha512', $enc, $macKey, true);
-		$data = bin2hex($salt . $enc . $mac);
-		return $data;
-
+		$mac = hash_hmac('sha512', $enc, (string)$macKey, true);
+		return bin2hex($salt . $enc . $mac);
 	}
 
 	/**
@@ -193,7 +199,7 @@ public function encrypt($data, $key) {
 	 *
 	 * @returns array An array of keys (a cipher key, a mac key, and a IV)
 	 */
-	protected function getKeys($salt, $key) {
+	protected function getKeys(string $salt, string $key): array {
 		$ivSize = openssl_cipher_iv_length($this->cipher);
 		$keySize = openssl_cipher_iv_length($this->cipher);
 		$length = 2 * $keySize + $ivSize;
@@ -219,7 +225,7 @@ protected function getKeys($salt, $key) {
 	 *
 	 * @returns string The derived key.
 	 */
-	protected function pbkdf2($algo, $key, $salt, $rounds, $length) {
+	protected function pbkdf2(string $algo, string $key, string $salt, int $rounds, int $length): string {
 		$size = strlen(hash($algo, '', true));
 		$len = ceil($length / $size);
 		$result = '';
@@ -238,10 +244,10 @@ protected function pbkdf2($algo, $key, $salt, $rounds, $length) {
 	/**
 	 * Pad the data with a random char chosen by the pad amount.
 	 *
-	 * @param $data
+	 * @param string $data
 	 * @return string
 	 */
-	protected function pad($data) {
+	protected function pad(string $data): string {
 		$length = $this->getKeySize();
 		$padAmount = $length - strlen($data) % $length;
 		if ($padAmount === 0) {
@@ -252,15 +258,20 @@ protected function pad($data) {
 
 
 	/**
-	 * Unpad the the data
+	 * Unpad the data
 	 *
-	 * @param $data
+	 * @param false|string $data
 	 * @return bool|string
 	 */
-	protected function unpad($data) {
+	protected function unpad(false|string $data): bool|string {
+		if ($data === false) {
+			return false;
+		}
 		$length = $this->getKeySize();
 		$last = ord($data[strlen($data) - 1]);
-		if ($last > $length) return false;
+		if ($last > $length) {
+			return false;
+		}
 		if (substr($data, -1 * $last) !== str_repeat(chr($last), $last)) {
 			return false;
 		}
@@ -269,24 +280,24 @@ protected function unpad($data) {
 
 
 	/**
-	 * Encrypt a credential
+	 * Decrypt a credential
 	 *
-	 * @param Credential|Entity|array $credential the credential to decrypt
-	 * @return Credential|array
+	 * @param Credential|array $credential the credential to decrypt
+	 * @return Credential|array modified $credential input object of the same type
 	 * @throws \Exception
 	 */
-	public function decryptCredential($credential) {
+	public function decryptCredential(Credential|array $credential): Credential|array {
 		return $this->handleCredential($credential, EncryptService::OP_DECRYPT);
 	}
 
 	/**
 	 * Encrypt a credential
 	 *
-	 * @param Credential|array $credential the credential to encrypt
-	 * @return Credential|array
+	 * @param array|Credential $credential the credential to encrypt
+	 * @return Credential|array modified $credential input object of the same type
 	 * @throws \Exception
 	 */
-	public function encryptCredential($credential) {
+	public function encryptCredential(Credential|array $credential): Credential|array {
 		return $this->handleCredential($credential, EncryptService::OP_ENCRYPT);
 	}
 
@@ -297,29 +308,30 @@ private function extractKeysFromCredential($credential) {
 		if ($credential instanceof Credential) {
 			$userSuppliedKey = $credential->getLabel();
 			$sk = $credential->getSharedKey();
-			$userKey = (isset($sk)) ? $sk : $credential->getUserId();
+			$userKey = $sk ?? $credential->getUserId();
 		}
 		if (is_array($credential)) {
 			$userSuppliedKey = $credential['label'];
-			$userKey = (isset($credential['shared_key'])) ? $credential['shared_key'] : $credential['user_id'];
+			$userKey = $credential['shared_key'] ?? $credential['user_id'];
 		}
 		return [$userKey, $userSuppliedKey];
 	}
 
 	/**
-	 * Handles the encryption / decryption of a credential
+	 * Handles the encryption / decryption of a credential.
+	 * This modifies the $credential parameter object, slightly different based on the passed parameter type.
 	 *
 	 * @param Credential|array $credential the credential to encrypt
-	 * @return Credential|array
+	 * @return Credential|array modified $credential input object of the same type
 	 * @throws \Exception
 	 */
-	private function handleCredential($credential, $service_function) {
-		list($userKey, $userSuppliedKey) = $this->extractKeysFromCredential($credential);
+	private function handleCredential(Credential|array $credential, $service_function): Credential|array {
+		[$userKey, $userSuppliedKey] = $this->extractKeysFromCredential($credential);
 
-		$key = $this->makeKey($userKey, $this->server_key, $userSuppliedKey);
+		$key = static::makeKey($userKey, $this->server_key, $userSuppliedKey);
 		foreach ($this->encrypted_credential_fields as $field) {
 			if ($credential instanceof Credential) {
-				$field = str_replace(' ', '', str_replace('_', ' ', ucwords($field, '_')));
+				$field = str_replace(' ', '', str_replace('_', ' ', ucwords((string)$field, '_')));
 				$set = 'set' . $field;
 				$get = 'get' . $field;
 				$credential->{$set}($this->{$service_function}($credential->{$get}(), $key));
@@ -335,33 +347,34 @@ private function handleCredential($credential, $service_function) {
 	/**
 	 * Encrypt a file
 	 *
-	 * @param File|array $file
-	 * @return File|array
+	 * @param array|File $file
+	 * @return array|File modified $file input object of the same type
 	 * @throws \Exception
 	 */
-	public function encryptFile($file) {
+	public function encryptFile(array|File $file): array|File {
 		return $this->handleFile($file, EncryptService::OP_ENCRYPT);
 	}
 
 	/**
 	 * Decrypt a file
 	 *
-	 * @param File|Entity|array $file
-	 * @return array|File
+	 * @param array|File $file
+	 * @return array|File modified $file input object of the same type
 	 * @throws \Exception
 	 */
-	public function decryptFile($file) {
+	public function decryptFile(array|File $file): array|File {
 		return $this->handleFile($file, EncryptService::OP_DECRYPT);
 	}
 
 	/**
-	 * Handles the encryption / decryption of a File
+	 * Handles the encryption / decryption of a File.
+	 * This modifies the $file parameter object, slightly different based on the passed parameter type.
 	 *
-	 * @param File|array $file the credential to encrypt
-	 * @return File|array
+	 * @param array|File $file the file to encrypt/decrypt
+	 * @return array|File modified $file input object of the same type
 	 * @throws \Exception
 	 */
-	private function handleFile($file, $service_function) {
+	private function handleFile(array|File $file, $service_function): array|File {
 		$userKey = '';
 		$userSuppliedKey = '';
 		if ($file instanceof File) {
@@ -371,10 +384,10 @@ private function handleFile($file, $service_function) {
 
 		if (is_array($file)) {
 			$userSuppliedKey = $file['size'];
-			$userKey = md5($file['mimetype']);
+			$userKey = md5((string)$file['mimetype']);
 		}
 
-		$key = $this->makeKey($userKey, $this->server_key, $userSuppliedKey);
+		$key = static::makeKey($userKey, $this->server_key, $userSuppliedKey);
 
 
 		if ($file instanceof File) {
diff --git a/lib/Service/FileService.php b/lib/Service/FileService.php
index 5a8e4bb76..f522513e2 100644
--- a/lib/Service/FileService.php
+++ b/lib/Service/FileService.php
@@ -27,7 +27,6 @@
 use OCA\Passman\Db\File;
 use OCA\Passman\Db\FileMapper;
 use OCP\AppFramework\Db\DoesNotExistException;
-use OCP\AppFramework\Db\Entity;
 use OCP\AppFramework\Db\MultipleObjectsReturnedException;
 use OCP\IConfig;
 
@@ -37,8 +36,8 @@ class FileService {
 	private $server_key;
 
 	public function __construct(
-		private FileMapper $fileMapper,
-		private EncryptService $encryptService,
+		private readonly FileMapper $fileMapper,
+		private readonly EncryptService $encryptService,
 		IConfig $config,
 	) {
 		$this->server_key = $config->getSystemValue('passwordsalt', '');
@@ -49,12 +48,12 @@ public function __construct(
 	 *
 	 * @param int $fileId
 	 * @param string|null $userId
-	 * @return array|File
+	 * @return File
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 * @throws Exception
 	 */
-	public function getFile(int $fileId, string $userId = null) {
+	public function getFile(int $fileId, ?string $userId = null): File {
 		$file = $this->fileMapper->getFile($fileId, $userId);
 		return $this->encryptService->decryptFile($file);
 	}
@@ -64,30 +63,30 @@ public function getFile(int $fileId, string $userId = null) {
 	 *
 	 * @param string $file_guid
 	 * @param string|null $userId
-	 * @return array|File
+	 * @return File
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 * @throws Exception
 	 */
-	public function getFileByGuid(string $file_guid, string $userId = null) {
+	public function getFileByGuid(string $file_guid, ?string $userId = null): File {
 		$file = $this->fileMapper->getFileByGuid($file_guid, $userId);
 		return $this->encryptService->decryptFile($file);
 	}
 
 	/**
-	 * Upload a new file,
+	 * Upload a new file
 	 *
 	 * @param array $file
 	 * @param string $userId
-	 * @return array|File
+	 * @return File
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 * @throws Exception
 	 */
-	public function createFile(array $file, string $userId) {
+	public function createFile(array $file, string $userId): File {
 		$file = $this->encryptService->encryptFile($file);
-		$file = $this->fileMapper->create($file, $userId);
-		return $this->getFile($file->getId());
+		$fileEntity = $this->fileMapper->create($file, $userId);
+		return $this->getFile($fileEntity->getId());
 	}
 
 	/**
@@ -95,9 +94,9 @@ public function createFile(array $file, string $userId) {
 	 *
 	 * @param int $file_id
 	 * @param string $userId
-	 * @return File|Entity
+	 * @return File
 	 */
-	public function deleteFile(int $file_id, string $userId) {
+	public function deleteFile(int $file_id, string $userId): File {
 		return $this->fileMapper->deleteFile($file_id, $userId);
 	}
 
@@ -108,7 +107,7 @@ public function deleteFile(int $file_id, string $userId) {
 	 * @return File
 	 * @throws Exception
 	 */
-	public function updateFile(File $file) {
+	public function updateFile(File $file): File {
 		$file = $this->encryptService->encryptFile($file);
 		return $this->fileMapper->updateFile($file);
 	}
@@ -120,11 +119,11 @@ public function updateFile(File $file) {
 	 * @return string[]
 	 * @throws Exception
 	 */
-	public function getFileGuidsFromUser(string $userId) {
-		$files = $this->fileMapper->getFileGuidsFromUser($userId);
+	public function getFileGuidsFromUser(string $userId): array {
+		$partialFiles = $this->fileMapper->getFileGuidsFromUser($userId);
 		$results = [];
-		foreach ($files as $fileGuid) {
-			$results[] = $fileGuid->getGuid();
+		foreach ($partialFiles as $partialFile) {
+			$results[] = $partialFile->getGuid();
 		}
 		return $results;
 	}
diff --git a/lib/Service/IconService.php b/lib/Service/IconService.php
index 4867854bf..fcb92f6f2 100644
--- a/lib/Service/IconService.php
+++ b/lib/Service/IconService.php
@@ -35,84 +35,84 @@ class IconService {
 	/**
 	 * @var string Page URL
 	 */
-	public $url;
+	public string $url;
 
 	/**
 	 * @var string Page URL, after prospective redirects
 	 */
-	public $pageUrl;
+	public string $pageUrl;
 
 	/**
 	 * @var string Site root URL (homepage), based on $pageUrl
 	 */
-	public $siteUrl;
+	public string $siteUrl;
 
 	/**
 	 * @var string full URI to favicon
 	 */
-	public $icoUrl;
+	public string $icoUrl;
 
 	/**
 	 * @var string favicon type (file extension, ex: ico|gif|png)
 	 */
-	public $icoType;
+	public string $icoType;
 
 	/**
 	 * @var string favicon url determination method (default /favicon.ico or found in head>link tag)
 	 */
-	public $findMethod;
+	public string $findMethod;
 
 	/**
 	 * @var string details, in case of failure
 	 */
-	public $error;
+	public string $error;
 
 	/**
 	 * @var bool tell if the favicon exists (set after calling IconService)
 	 */
-	public $icoExists;
+	public bool $icoExists;
 
 	/**
 	 * @var string md5 of $icoData
 	 */
-	public $icoMd5;
+	public string $icoMd5;
 
 	/**
 	 * @var string favicon binary data
 	 */
-	public $icoData;
+	public string $icoData;
 
 	/**
 	 * @var array Additional debug info
 	 */
-	public $debugInfo;
+	public array $debugInfo;
 
 	/**
-	 * @var string HTTP proxy (ex: localhost:8888)
+	 * @var string|null HTTP proxy (ex: localhost:8888)
 	 */
-	protected $httpProxy;
+	protected mixed $httpProxy;
 
 	/**
 	 * @var bool SSL verify peer (default: true)
 	 */
-	protected $sslVerify;
+	protected bool $sslVerify;
 
 	/**
 	 * Create a new IconService object, search & download favicon if $auto is true
 	 *
 	 * @param string $url Page URL
-	 * @param array $options Optional settings
+	 * @param array|null $options Optional settings
 	 * @param bool $auto Search & download favicon on instantiation
 	 */
-	public function __construct($url, $options = null, $auto = true) {
-		if (!$url) {
+	public function __construct(string $url, ?array $options = null, bool $auto = true) {
+		if (empty($url)) {
 			throw new \InvalidArgumentException("url is empty");
 		}
 		if (self::urlType($url) != self::URL_TYPE_ABSOLUTE) {
 			throw new \InvalidArgumentException("'" . $url . "' is not an absolute url");
 		}
 		$this->url = $url;
-		$this->httpProxy = isset($options['httpProxy']) ? $options['httpProxy'] : null;
+		$this->httpProxy = $options['httpProxy'] ?? null;
 		$this->sslVerify = isset($options['sslVerify']) && $options['sslVerify'] === false ? false : true;
 		if ($auto) {
 			$this->getFaviconUrl();
@@ -164,12 +164,12 @@ public function getFaviconUrl() {
 		$this->findMethod = 'default';
 
 		// HTML <head> tag extraction
-		preg_match('#^(.*)<\s*body#isU', $html, $matches);
-		$htmlHead = isset($matches[1]) ? $matches[1] : $html;
+		preg_match('#^(.*)<\s*body#isU', (string) $html, $matches);
+		$htmlHead = $matches[1] ?? $html;
 
 		// HTML <base> tag href extraction
 		$base_href = null;
-		if (preg_match('#<base[^>]+href=(["\'])([^>]+)\1#i', $htmlHead, $matches)) {
+		if (preg_match('#<base[^>]+href=(["\'])([^>]+)\1#i', (string) $htmlHead, $matches)) {
 			$base_href = rtrim($matches[2], '/') . '/';
 			$this->debugInfo['base_href'] = $base_href;
 		}
@@ -182,7 +182,7 @@ public function getFaviconUrl() {
 
 
 	private function parseLinkElement($htmlHead, $pageUrlInfo, $base_href){
-		if (preg_match('#<\s*link[^>]*(rel=(["\'])[^>\2]*icon[^>\2]*\2)[^>]*>#i', $htmlHead, $matches)) {
+		if (preg_match('#<\s*link[^>]*(rel=(["\'])[^>\2]*icon[^>\2]*\2)[^>]*>#i', (string) $htmlHead, $matches)) {
 			$link_tag = $matches[0];
 			$this->debugInfo['link_tag'] = $link_tag;
 
@@ -224,7 +224,7 @@ private function parseLinkElement($htmlHead, $pageUrlInfo, $base_href){
 						break;
 					case self::URL_TYPE_RELATIVE:
 						$this->findMethod .= ' relative';
-						$path = preg_replace('#/[^/]+?$#i', '/', $pageUrlInfo['path']);
+						$path = preg_replace('#/[^/]+?$#i', '/', (string) $pageUrlInfo['path']);
 						$this->icoUrl = $pageUrlInfo['scheme'] . '://' . $pageUrlInfo['host'] . $path . $ico_href;
 						$this->findMethod .= ' without base href';
 						if (isset($base_href)) {
@@ -297,19 +297,19 @@ public function downloadFavicon() {
 		}
 
 		// Check favicon content
-		if (strlen($content) == 0) {
+		if (strlen((string) $content) == 0) {
 			$this->error = "Empty content";
 			return false;
 		}
 		$textTypes = ['text/html', 'text/plain'];
-		if (in_array($info['content_type'], $textTypes) || preg_match('#(</html>|</b>)#i', $content)) {
+		if (in_array($info['content_type'], $textTypes) || preg_match('#(</html>|</b>)#i', (string) $content)) {
 			$this->error = "Seems to be a text document";
 			return false;
 		}
 
 		// All right baby !
 		$this->icoData = $content;
-		$this->icoMd5 = md5($content);
+		$this->icoMd5 = md5((string) $content);
 		$this->icoExists = true;
 		return true;
 	}
@@ -350,7 +350,7 @@ public function downloadAs($url, &$info = null) {
 		$info['content_type'] = curl_getinfo($ch, CURLINFO_CONTENT_TYPE);
 		curl_close($ch);
 
-		if ($info['curl_errno'] !== CURLE_OK || in_array($info['http_code'], array(403, 404, 500, 503))) {
+		if ($info['curl_errno'] !== CURLE_OK || in_array($info['http_code'], [403, 404, 500, 503])) {
 			return false;
 		}
 		return $content;
@@ -400,9 +400,10 @@ public static function getExtensionFromMimeType($mimeType) {
 	 * - URL_TYPE_RELATIVE        ex: ../images/fav.ico
 	 * - URL_TYPE_EMBED_BASE64    ex: data:image/x-icon;base64,AAABAA...
 	 *
-	 * @return int
+	 * @param string $url
+	 * @return false|int
 	 */
-	public static function urlType($url) {
+	public static function urlType(string $url): false|int {
 		if (empty($url)) {
 			return false;
 		}
diff --git a/lib/Service/NotificationService.php b/lib/Service/NotificationService.php
index 03ba6e714..df07b9bd4 100644
--- a/lib/Service/NotificationService.php
+++ b/lib/Service/NotificationService.php
@@ -31,9 +31,9 @@
 
 class NotificationService {
 	public function __construct(
-		private IManager $manager,
-		private IURLGenerator $urlGenerator,
-		private IDBConnection $db,
+		private readonly IManager $manager,
+		private readonly IURLGenerator $urlGenerator,
+		private readonly IDBConnection $db,
 	) {
 	}
 
diff --git a/lib/Service/SettingsService.php b/lib/Service/SettingsService.php
index fa20d20ca..f7da1f94a 100644
--- a/lib/Service/SettingsService.php
+++ b/lib/Service/SettingsService.php
@@ -28,8 +28,6 @@
 
 class SettingsService {
 
-	private $userId;
-	private $appName;
 	public $settings;
 
 	private $numeric_settings = [
@@ -44,12 +42,10 @@ class SettingsService {
 	];
 
 	public function __construct(
-		$UserId,
-		private IConfig $config,
-		$AppName,
+		private $userId,
+		private readonly IConfig $config,
+		private $appName,
 	) {
-		$this->userId = $UserId;
-		$this->appName = $AppName;
 		$this->settings = [
 			'link_sharing_enabled' => intval($this->config->getAppValue('passman', 'link_sharing_enabled', 1)),
 			'user_sharing_enabled' => intval($this->config->getAppValue('passman', 'user_sharing_enabled', 1)),
@@ -82,7 +78,7 @@ public function getAppSettings() {
 	 * @return mixed
 	 */
 	public function getAppSetting($key, $default_value = null) {
-		$value = ($this->settings[$key]) ? $this->settings[$key] : $this->config->getAppValue('passman', $key, $default_value);
+		$value = $this->settings[$key] ?: $this->config->getAppValue('passman', $key, $default_value);
 		if (in_array($key, $this->numeric_settings)) {
 			$value = intval($value);
 		}
diff --git a/lib/Service/ShareService.php b/lib/Service/ShareService.php
index 4db20777d..299257ce7 100644
--- a/lib/Service/ShareService.php
+++ b/lib/Service/ShareService.php
@@ -25,26 +25,25 @@
 
 
 use OCA\Passman\Db\CredentialMapper;
+use OCA\Passman\Db\CredentialRevision;
 use OCA\Passman\Db\ShareRequest;
 use OCA\Passman\Db\ShareRequestMapper;
 use OCA\Passman\Db\SharingACL;
 use OCA\Passman\Db\SharingACLMapper;
 use OCA\Passman\Utility\Utils;
 use OCP\AppFramework\Db\DoesNotExistException;
-use OCP\AppFramework\Db\Entity;
 use OCP\AppFramework\Db\MultipleObjectsReturnedException;
 use OCP\DB\Exception;
-use OCP\DB\IResult;
 use OCP\Notification\IManager;
 
 class ShareService {
 	public function __construct(
-		private SharingACLMapper $sharingACL,
-		private ShareRequestMapper $shareRequest,
-		private CredentialMapper $credential,
-		private CredentialRevisionService $revisions,
-		private EncryptService $encryptService,
-		private IManager $IManager,
+		private readonly SharingACLMapper $sharingACL,
+		private readonly ShareRequestMapper $shareRequest,
+		private readonly CredentialMapper $credential,
+		private readonly CredentialRevisionService $revisions,
+		private readonly EncryptService $encryptService,
+		private readonly IManager $IManager,
 	) {
 	}
 
@@ -83,10 +82,12 @@ public function createBulkRequests($target_item_id, $target_item_guid, $request_
 
 	/**
 	 * @param SharingACL $acl
-	 * @return Entity
+	 * @return SharingACL
 	 */
-	public function createACLEntry(SharingACL $acl) {
-		if ($acl->getCreated() === null) $acl->setCreated((new \DateTime())->getTimestamp());
+	public function createACLEntry(SharingACL $acl): SharingACL {
+		if ($acl->getCreated() === null) {
+			$acl->setCreated((new \DateTime())->getTimestamp());
+		}
 		return $this->sharingACL->createACLEntry($acl);
 	}
 
@@ -100,7 +101,7 @@ public function createACLEntry(SharingACL $acl) {
 	 * @throws Exception
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function applyShare(string $item_guid, string $target_vault_guid, string $final_shared_key) {
+	public function applyShare(string $item_guid, string $target_vault_guid, string $final_shared_key): void {
 		$request = $this->shareRequest->getRequestByItemAndVaultGuid($item_guid, $target_vault_guid);
 		$permissions = $request->getPermissions();
 
@@ -123,9 +124,9 @@ public function applyShare(string $item_guid, string $target_vault_guid, string
 	 * Obtains pending requests for the given user ID
 	 *
 	 * @param string $user_id
-	 * @return Entity[]
+	 * @return SharingACL[]
 	 */
-	public function getUserPendingRequests(string $user_id) {
+	public function getUserPendingRequests(string $user_id): array {
 		return $this->shareRequest->getUserPendingRequests($user_id);
 	}
 
@@ -138,114 +139,126 @@ public function getUserPendingRequests(string $user_id) {
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getSharedItems(string $user_id, string $vault_guid) {
-		$entries = $this->sharingACL->getVaultEntries($user_id, $vault_guid);
+	public function getSharedItems(string $user_id, string $vault_guid): array {
+		$acceptedVaultShareRequests = $this->sharingACL->getVaultEntries($user_id, $vault_guid);
 
 		$return = [];
-		foreach ($entries as $entry) {
-			// Check if the user can read the credential, probably unnecesary, but just to be sure
-			if (!$entry->hasPermission(SharingACL::READ)) continue;
-			$tmp = $entry->jsonSerialize();
-			$credential = $this->credential->getCredentialById($entry->getItemId());
-			$credential = $this->encryptService->decryptCredential($credential);
-			$tmp['credential_data'] = $credential->jsonSerialize();
-
-			if (!$entry->hasPermission(SharingACL::FILES)) unset($tmp['credential_data']['files']);
-			unset($tmp['credential_data']['shared_key']);
-			$return[] = $tmp;
+		foreach ($acceptedVaultShareRequests as $acceptedVaultShareRequest) {
+			$serializableVaultShareRequest = $this->prepareSharedItemForResponse($acceptedVaultShareRequest);
+			if (!empty($serializableVaultShareRequest)) {
+				$return[] = $serializableVaultShareRequest;
+			}
 		}
 		return $return;
 	}
 
 	/**
-	 * Gets the acl for a given item guid
+	 * Get shared credential (from a user)
 	 *
-	 * @param string $user_id
+	 * @param string|null $user_id
 	 * @param string $item_guid
-	 * @return Entity
+	 * @return array
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getACL(?string $user_id, string $item_guid) {
-		return $this->sharingACL->getItemACL($user_id, $item_guid);
+	public function getSharedItem(?string $user_id, string $item_guid): array {
+		$acl = $this->sharingACL->getItemACL($user_id, $item_guid);
+
+		$serializableItemACL = $this->prepareSharedItemForResponse($acl);
+		if (empty($serializableItemACL)) {
+			throw new DoesNotExistException("Item not found or wrong access level");
+		}
+		return $serializableItemACL;
 	}
 
 	/**
-	 * @param string $user_id
-	 * @param string $item_guid
-	 * @return array|mixed
-	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
+	 * @throws DoesNotExistException
 	 */
-	public function getSharedItem(?string $user_id, string $item_guid) {
-		$acl = $this->sharingACL->getItemACL($user_id, $item_guid);
-
-		// Check if the user can read the credential, probably unnecesary, but just to be sure
-		if (!$acl->hasPermission(SharingACL::READ)) throw new DoesNotExistException("Item not found or wrong access level");
+	private function prepareSharedItemForResponse(SharingACL $sharingACL): array|null {
+		// Check if the user can read the credential, probably unnecessary, but just to be sure
+		if (!$sharingACL->hasPermission(SharingACL::READ)) {
+			return null;
+		}
 
-		$tmp = $acl->jsonSerialize();
-		$credential = $this->credential->getCredentialById($acl->getItemId());
+		$credential = $this->credential->getCredentialById($sharingACL->getItemId());
 		$credential = $this->encryptService->decryptCredential($credential);
 
-		$tmp['credential_data'] = $credential->jsonSerialize();
+		$serializableSharingACL = $sharingACL->jsonSerialize();
+		$serializableSharingACL['credential_data'] = $credential->jsonSerialize();
 
-		if (!$acl->hasPermission(SharingACL::FILES)) unset($tmp['credential_data']['files']);
-		unset($tmp['credential_data']['shared_key']);
+		if (!$sharingACL->hasPermission(SharingACL::FILES)) {
+			unset($serializableSharingACL['credential_data']['files']);
+		}
+		unset($serializableSharingACL['credential_data']['shared_key']);
+		return $serializableSharingACL;
+	}
 
-		return $tmp;
+	/**
+	 * Gets the acl for a given item guid
+	 *
+	 * @param string|null $user_id
+	 * @param string $item_guid
+	 * @return SharingACL
+	 * @throws DoesNotExistException
+	 * @throws MultipleObjectsReturnedException
+	 */
+	public function getACL(?string $user_id, string $item_guid): SharingACL {
+		return $this->sharingACL->getItemACL($user_id, $item_guid);
 	}
 
 	/**
 	 * Gets history from the given item checking the user's permissions to access it
 	 *
-	 * @param string $user_id
+	 * @param string|null $user_id
 	 * @param string $item_guid
-	 * @return array|Entity[]
+	 * @return array|CredentialRevision[]
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
-	 * @throws \Exception
 	 */
-	public function getItemHistory(?string $user_id, string $item_guid) {
+	public function getItemHistory(?string $user_id, string $item_guid): array {
 		$acl = $this->sharingACL->getItemACL($user_id, $item_guid);
-		if (!$acl->hasPermission(SharingACL::READ | SharingACL::HISTORY)) return [];
+		if (!$acl->hasPermission(SharingACL::READ | SharingACL::HISTORY)) {
+			return [];
+		}
 
 		return $this->revisions->getRevisions($acl->getItemId());
 	}
 
 
 	/**
-	 * Deletes a share request by the item ID
+	 * Deletes a share request by the item id
 	 *
 	 * @param ShareRequest $request
-	 * @return int|IResult
+	 * @return int
 	 * @throws Exception
 	 */
-	public function cleanItemRequestsForUser(ShareRequest $request) {
+	public function cleanItemRequestsForUser(ShareRequest $request): int {
 		return $this->shareRequest->cleanItemRequestsForUser($request->getItemId(), $request->getTargetUserId());
 	}
 
 	/**
-	 * Get an share request by id
+	 * Get a share request by id
 	 *
 	 * @param int $id
-	 * @return Entity
+	 * @return ShareRequest
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getShareRequestById(int $id) {
+	public function getShareRequestById(int $id): ShareRequest {
 		return $this->shareRequest->getShareRequestById($id);
 	}
 
 	/**
-	 * Get an share request by $item_guid and $target_vault_guid
+	 * Get a share request by $item_guid and $target_vault_guid
 	 *
 	 * @param string $item_guid
 	 * @param string $target_vault_guid
-	 * @return Entity
+	 * @return ShareRequest
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getRequestByGuid(string $item_guid, string $target_vault_guid) {
+	public function getRequestByGuid(string $item_guid, string $target_vault_guid): ShareRequest {
 		return $this->shareRequest->getRequestByItemAndVaultGuid($item_guid, $target_vault_guid);
 	}
 
@@ -253,9 +266,9 @@ public function getRequestByGuid(string $item_guid, string $target_vault_guid) {
 	 * Get the access control list by item guid
 	 *
 	 * @param string $item_guid
-	 * @return Entity[]
+	 * @return SharingACL[]
 	 */
-	public function getCredentialAclList(string $item_guid) {
+	public function getCredentialAclList(string $item_guid): array {
 		return $this->sharingACL->getCredentialAclList($item_guid);
 	}
 
@@ -264,31 +277,31 @@ public function getCredentialAclList(string $item_guid) {
 	 *
 	 * @param string $user_id
 	 * @param string $vault_guid
-	 * @return Entity[]
+	 * @return SharingACL[]
 	 */
-	public function getVaultAclList(string $user_id, string $vault_guid) {
+	public function getVaultAclList(string $user_id, string $vault_guid): array {
 		return $this->sharingACL->getVaultEntries($user_id, $vault_guid);
 	}
 
 	/**
 	 * @param string $item_guid
-	 * @return Entity[]
+	 * @return ShareRequest[]
 	 * @throws Exception
 	 */
-	public function getCredentialPendingAclList(string $item_guid) {
+	public function getCredentialPendingAclList(string $item_guid): array {
 		return $this->shareRequest->getRequestsByItemGuid($item_guid);
 	}
 
 	/**
 	 * Gets the ACL on the credential for the user
 	 *
-	 * @param string $user_id
+	 * @param string|null $user_id
 	 * @param string $item_guid
-	 * @return Entity
+	 * @return SharingACL
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getCredentialAclForUser(?string $user_id, string $item_guid) {
+	public function getCredentialAclForUser(?string $user_id, string $item_guid): SharingACL {
 		return $this->sharingACL->getItemACL($user_id, $item_guid);
 	}
 
@@ -296,9 +309,9 @@ public function getCredentialAclForUser(?string $user_id, string $item_guid) {
 	 * Get pending share requests by guid
 	 *
 	 * @param string $item_guid
-	 * @return Entity[]
+	 * @return ShareRequest[]
 	 */
-	public function getShareRequestsByGuid(string $item_guid) {
+	public function getShareRequestsByGuid(string $item_guid): array {
 		return $this->shareRequest->getShareRequestsByItemGuid($item_guid);
 	}
 
@@ -308,27 +321,27 @@ public function getShareRequestsByGuid(string $item_guid) {
 	 * @param ShareRequest $request
 	 * @return ShareRequest
 	 */
-	public function deleteShareRequest(ShareRequest $request) {
+	public function deleteShareRequest(ShareRequest $request): ShareRequest {
 		return $this->shareRequest->deleteShareRequest($request);
 	}
 
 	/**
 	 * Delete ACL
 	 *
-	 * @param SharingACL|Entity $ACL
-	 * @return SharingACL|Entity
+	 * @param SharingACL $sharingACL
+	 * @return SharingACL
 	 */
-	public function deleteShareACL(SharingACL $ACL) {
-		return $this->sharingACL->deleteShareACL($ACL);
+	public function deleteShareACL(SharingACL $sharingACL): SharingACL {
+		return $this->sharingACL->deleteShareACL($sharingACL);
 	}
 
 	/**
 	 * Updates the given ACL entry
 	 *
 	 * @param SharingACL $sharingACL
-	 * @return SharingACL|Entity
+	 * @return SharingACL
 	 */
-	public function updateCredentialACL(SharingACL $sharingACL) {
+	public function updateCredentialACL(SharingACL $sharingACL): SharingACL {
 		return $this->sharingACL->updateCredentialACL($sharingACL);
 	}
 
@@ -336,7 +349,7 @@ public function updateCredentialACL(SharingACL $sharingACL) {
 	 * @param ShareRequest $shareRequest
 	 * @return ShareRequest
 	 */
-	public function updateCredentialShareRequest(ShareRequest $shareRequest) {
+	public function updateCredentialShareRequest(ShareRequest $shareRequest): ShareRequest {
 		return $this->shareRequest->updateShareRequest($shareRequest);
 	}
 
@@ -346,9 +359,9 @@ public function updateCredentialShareRequest(ShareRequest $shareRequest) {
 	 *
 	 * @param string $item_guid
 	 * @param string $user_id
-	 * @return Entity[]
+	 * @return ShareRequest[]
 	 */
-	public function getPendingShareRequestsForCredential(string $item_guid, string $user_id) {
+	public function getPendingShareRequestsForCredential(string $item_guid, string $user_id): array {
 		return $this->shareRequest->getPendingShareRequests($item_guid, $user_id);
 	}
 
@@ -356,10 +369,10 @@ public function getPendingShareRequestsForCredential(string $item_guid, string $
 	 * @param string $item_guid
 	 * @param string $user_id
 	 * @param int $permissions
-	 * @return int|IResult
+	 * @return int
 	 * @throws Exception
 	 */
-	public function updatePendingShareRequestsForCredential(string $item_guid, string $user_id, int $permissions) {
+	public function updatePendingShareRequestsForCredential(string $item_guid, string $user_id, int $permissions): int {
 		return $this->shareRequest->updatePendingRequestPermissions($item_guid, $user_id, $permissions);
 	}
 
@@ -368,7 +381,7 @@ public function updatePendingShareRequestsForCredential(string $item_guid, strin
 	 * This will delete all ACL's and share requests.
 	 * @param string $item_guid
 	 */
-	public function unshareCredential(string $item_guid) {
+	public function unshareCredential(string $item_guid): void {
 		$acl_list = $this->getCredentialAclList($item_guid);
 		$request_list = $this->getShareRequestsByGuid($item_guid);
 		foreach ($acl_list as $ACL) {
diff --git a/lib/Service/VaultService.php b/lib/Service/VaultService.php
index 7687d1997..f7a1a899b 100644
--- a/lib/Service/VaultService.php
+++ b/lib/Service/VaultService.php
@@ -26,14 +26,13 @@
 use OCA\Passman\Db\Vault;
 use OCA\Passman\Db\VaultMapper;
 use OCP\AppFramework\Db\DoesNotExistException;
-use OCP\AppFramework\Db\Entity;
 use OCP\AppFramework\Db\MultipleObjectsReturnedException;
 
 
 class VaultService {
 
 	public function __construct(
-		private VaultMapper $vaultMapper,
+		private readonly VaultMapper $vaultMapper,
 	) {
 
 	}
@@ -41,9 +40,9 @@ public function __construct(
 	/**
 	 * Get vaults from a user.
 	 * @param $userId
-	 * @return Entity[]
+	 * @return Vault[]
 	 */
-	public function getByUser($userId) {
+	public function getByUser($userId): array {
 		return $this->vaultMapper->findVaultsFromUser($userId);
 	}
 
@@ -51,21 +50,21 @@ public function getByUser($userId) {
 	 * Get a single vault
 	 * @param $vault_id
 	 * @param $user_id
-	 * @return Entity[]
+	 * @return Vault
 	 */
-	public function getById($vault_id, $user_id) {
-		return $this->vaultMapper->find($vault_id, $user_id);
+	public function getById($vault_id, $user_id): Vault {
+		return $this->vaultMapper->findById($vault_id, $user_id);
 	}
 
 	/**
 	 * Get a single vault.
 	 * @param $vault_guid
 	 * @param $user_id
-	 * @return Entity
+	 * @return Vault
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function getByGuid($vault_guid, $user_id) {
+	public function getByGuid($vault_guid, $user_id): Vault {
 		return $this->vaultMapper->findByGuid($vault_guid, $user_id);
 	}
 
@@ -75,16 +74,16 @@ public function getByGuid($vault_guid, $user_id) {
 	 * @param $userId
 	 * @return Vault
 	 */
-	public function createVault($vault_name, $userId) {
+	public function createVault($vault_name, $userId): Vault {
 		return $this->vaultMapper->create($vault_name, $userId);
 	}
 
 	/**
 	 * Update vault
 	 * @param $vault
-	 * @return Vault|Entity
+	 * @return Vault
 	 */
-	public function updateVault($vault) {
+	public function updateVault($vault): Vault {
 		return $this->vaultMapper->updateVault($vault);
 	}
 
@@ -92,9 +91,9 @@ public function updateVault($vault) {
 	 * Update last access time of a vault.
 	 * @param $vault_id
 	 * @param $user_id
-	 * @return Vault|Entity
+	 * @return Vault
 	 */
-	public function setLastAccess($vault_id, $user_id) {
+	public function setLastAccess($vault_id, $user_id): Vault {
 		return $this->vaultMapper->setLastAccess($vault_id, $user_id);
 	}
 
@@ -103,9 +102,9 @@ public function setLastAccess($vault_id, $user_id) {
 	 * @param $vault_id
 	 * @param $privateKey
 	 * @param $publicKey
-	 * @return Vault|Entity
+	 * @return Vault
 	 */
-	public function updateSharingKeys($vault_id, $privateKey, $publicKey) {
+	public function updateSharingKeys($vault_id, $privateKey, $publicKey): Vault {
 		return $this->vaultMapper->updateSharingKeys($vault_id, $privateKey, $publicKey);
 	}
 
@@ -116,10 +115,8 @@ public function updateSharingKeys($vault_id, $privateKey, $publicKey) {
 	 * @throws DoesNotExistException
 	 * @throws MultipleObjectsReturnedException
 	 */
-	public function deleteVault($vault_guid, $user_id) {
+	public function deleteVault($vault_guid, $user_id): void {
 		$vault = $this->getByGuid($vault_guid, $user_id);
-		if ($vault instanceof Vault) {
-			$this->vaultMapper->deleteVault($vault);
-		}
+		$this->vaultMapper->deleteVault($vault);
 	}
 }
diff --git a/lib/Settings/Admin.php b/lib/Settings/Admin.php
index ec7cb60ad..928d2406c 100644
--- a/lib/Settings/Admin.php
+++ b/lib/Settings/Admin.php
@@ -24,6 +24,7 @@
 namespace OCA\Passman\Settings;
 
 use GuzzleHttp\Client;
+use GuzzleHttp\Exception\GuzzleException;
 use OCP\App\IAppManager;
 use OCP\AppFramework\Http\TemplateResponse;
 use OCP\IConfig;
@@ -41,9 +42,9 @@ class Admin implements ISettings {
 	 */
 	public function __construct(
 		protected IConfig $config,
-		private IL10N $l,
-		private IAppManager $appManager,
-		private LoggerInterface $logger,
+		private readonly IL10N $l,
+		private readonly IAppManager $appManager,
+		private readonly LoggerInterface $logger,
 	) {
 	}
 
@@ -66,8 +67,8 @@ public function getForm(): TemplateResponse {
 				$response = $httpClient->request('get', $url);
 				$json = $response->getBody()->getContents();
 
-				if ($json) {
-					$data = json_decode($json);
+				if (!empty($json)) {
+					$data = json_decode((string) $json);
 					if (isset($data->tag_name) && is_string($data->tag_name)) {
 						$githubVersion = $data->tag_name;
 
@@ -76,7 +77,7 @@ public function getForm(): TemplateResponse {
 						}
 					}
 				}
-			} catch (\Exception $e) {
+			} catch (\Exception|GuzzleException $e) {
 				$this->logger->error('Error fetching latest GitHub release version in lib/Admin:getForm()',
 					['exception' => $e->getTrace(), 'message' => $e->getMessage()]);
 			}
diff --git a/rector.php b/rector.php
new file mode 100644
index 000000000..426341255
--- /dev/null
+++ b/rector.php
@@ -0,0 +1,29 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+use Rector\Config\RectorConfig;
+
+return RectorConfig::configure()
+	->withPaths([
+		__DIR__ . '/appinfo',
+		__DIR__ . '/lib',
+		__DIR__ . '/templates',
+		__DIR__ . '/tests',
+	])
+	->withPhpSets(php84: true)
+	->withTypeCoverageLevel(0)
+	->withSkip([
+		// skip rule since it marks code that's intended, as it is
+		\Rector\Php70\Rector\FuncCall\RandomFunctionRector::class,
+
+		// skip rule since it's introduced with php8.4 and not compatible to php8.1
+		\Rector\Php84\Rector\MethodCall\NewMethodCallWithoutParenthesesRector::class,
+		// skip rule since it's introduced with php8.3 and not compatible to php8.1
+		\Rector\Php83\Rector\ClassMethod\AddOverrideAttributeToOverriddenMethodsRector::class
+	]);
diff --git a/tests/db/DatabaseHelperTest.php b/tests/db/DatabaseHelperTest.php
index cd5fe26b8..554eafaf3 100644
--- a/tests/db/DatabaseHelperTest.php
+++ b/tests/db/DatabaseHelperTest.php
@@ -80,12 +80,12 @@ public function truncateTable($table_name) {
 		$this->db->executeQuery($this->db->getDatabasePlatform()->getTruncateTableSQL($table_name));
 	}
 
-	/**
-	 * Initializes the table with the corresponding dataset on the dumps dir
-	 *
-	 * @param $table_name
-	 */
-	public function setUpTable($table_name){
+    /**
+     * Initializes the table with the corresponding dataset on the dumps dir
+     *
+     * @param string $table_name
+     */
+	public function setUpTable(string $table_name){
 		$table = $this->getTableDataset($table_name);
 		$table_no_prefix = substr($table_name, 3);
 
diff --git a/tests/unit/controller/InternalControllerTest.php b/tests/unit/controller/InternalControllerTest.php
index 7f5ad49ba..b69f53738 100644
--- a/tests/unit/controller/InternalControllerTest.php
+++ b/tests/unit/controller/InternalControllerTest.php
@@ -41,7 +41,7 @@ class InternalControllerTest extends PHPUnit_Framework_TestCase {
 	public function setUp() {
 		$request = $this->getMockBuilder('OCP\IRequest')->getMock();
 		$config = $this->getMockBuilder('OCP\IConfig')->getMock();
-		$this->credentialService = $this->getMockBuilder('OCA\Passman\Service\CredentialService')
+		$this->credentialService = $this->getMockBuilder(\OCA\Passman\Service\CredentialService::class)
 			->disableOriginalConstructor()
 			->getMock();
 		$this->controller = new InternalController(
diff --git a/tests/unit/lib/BackgroundJob/ExpireCredentialsTest.php b/tests/unit/lib/BackgroundJob/ExpireCredentialsTest.php
index 836a3b091..ef2da6036 100644
--- a/tests/unit/lib/BackgroundJob/ExpireCredentialsTest.php
+++ b/tests/unit/lib/BackgroundJob/ExpireCredentialsTest.php
@@ -46,7 +46,7 @@ public function testRun() {
 		try {
 		    $backgroundJob->execute($jobList);
 		}
-		catch (Exception $ex) {
+		catch (Exception) {
 		    $this->assertTrue(false);
 		}
 	}
diff --git a/tests/unit/lib/Db/CredentialMapperTest.php b/tests/unit/lib/Db/CredentialMapperTest.php
index 525d29612..9fdb3c973 100644
--- a/tests/unit/lib/Db/CredentialMapperTest.php
+++ b/tests/unit/lib/Db/CredentialMapperTest.php
@@ -106,8 +106,7 @@ public function testGetRandomCredentialByVaultId() {
 		$tmp = $this->filterDataset($tmp, 'id', $data[0]->getId());
 		$this->assertCount(count($tmp), $data);
 
-		$tmp[0] = Credential::fromRow($tmp[0]);
-		$this->assertEquals($tmp, $data);
+		$this->assertEquals(Credential::fromRow($tmp[0]), $data);
 	}
 
 	/**
@@ -286,4 +285,4 @@ public function testUpd() {
 			$this->mapper->getCredentialById($cred->getId())->jsonSerialize()
 		);
 	}
-}
\ No newline at end of file
+}
diff --git a/tests/unit/lib/Service/IconServiceTest.php b/tests/unit/lib/Service/IconServiceTest.php
index 4f4f2657c..0c7a7ac46 100644
--- a/tests/unit/lib/Service/IconServiceTest.php
+++ b/tests/unit/lib/Service/IconServiceTest.php
@@ -39,9 +39,9 @@ class IconServiceTest extends PHPUnit_Framework_TestCase {
 	private $testKey;
 
 	public function setUp() {
-		$this->options = array(
+		$this->options = [
 			'sslVerify' => false,
-		);
+		];
 
 	}