diff --git a/lib/AppInfo/Application.php b/lib/AppInfo/Application.php
index ccce228..fb1acb8 100644
--- a/lib/AppInfo/Application.php
+++ b/lib/AppInfo/Application.php
@@ -19,7 +19,7 @@
 use OCP\IRequest;
 use Psr\Log\LoggerInterface;
 
-class Application extends App implements IBootstrap {
+final class Application extends App implements IBootstrap {
 	public function __construct() {
 		parent::__construct('admin_audit_http_client');
 	}
diff --git a/lib/Http/Client/LoggingClientService.php b/lib/Http/Client/LoggingClientService.php
index 150e15e..cf1116a 100644
--- a/lib/Http/Client/LoggingClientService.php
+++ b/lib/Http/Client/LoggingClientService.php
@@ -16,7 +16,7 @@
 use OCP\IRequest;
 use Psr\Log\LoggerInterface;
 
-class LoggingClientService implements IClientService {
+final class LoggingClientService implements IClientService {
 	public function __construct(
 		private IClientService $inner,
 		private LoggerInterface $logger,
diff --git a/lib/Http/Client/Middleware/CountingStream.php b/lib/Http/Client/Middleware/CountingStream.php
index 1133f9c..716e204 100644
--- a/lib/Http/Client/Middleware/CountingStream.php
+++ b/lib/Http/Client/Middleware/CountingStream.php
@@ -17,7 +17,7 @@
  * entry once the body has been fully consumed (close) or garbage collected
  * (__destruct fallback for streams that are never explicitly closed).
  */
-class CountingStream implements StreamInterface {
+final class CountingStream implements StreamInterface {
 	private int $bytesRead = 0;
 	private bool $logged = false;
 
diff --git a/lib/Http/Client/Middleware/HttpClientLoggerMiddleware.php b/lib/Http/Client/Middleware/HttpClientLoggerMiddleware.php
index 5fb29de..ce3db81 100644
--- a/lib/Http/Client/Middleware/HttpClientLoggerMiddleware.php
+++ b/lib/Http/Client/Middleware/HttpClientLoggerMiddleware.php
@@ -16,7 +16,7 @@
 use Psr\Http\Message\ResponseInterface;
 use Psr\Log\LoggerInterface;
 
-class HttpClientLoggerMiddleware {
+final class HttpClientLoggerMiddleware {
 	/**
 	 * Same placeholder the server itself uses when it strips sensitive
 	 * values from config output.
diff --git a/lib/Http/Client/Middleware/LogPathHelper.php b/lib/Http/Client/Middleware/LogPathHelper.php
index 543a11f..f82e488 100644
--- a/lib/Http/Client/Middleware/LogPathHelper.php
+++ b/lib/Http/Client/Middleware/LogPathHelper.php
@@ -9,7 +9,7 @@
 
 namespace OCA\AdminAuditHttpClient\Http\Client\Middleware;
 
-class LogPathHelper {
+final class LogPathHelper {
 	/**
 	 * Derives per-host log file paths from request meta info.
 	 *
diff --git a/lib/Http/Client/Middleware/LogWriter.php b/lib/Http/Client/Middleware/LogWriter.php
index fe5a7b5..082b8ba 100644
--- a/lib/Http/Client/Middleware/LogWriter.php
+++ b/lib/Http/Client/Middleware/LogWriter.php
@@ -16,7 +16,7 @@
  * reports the first failed write per process as a warning — without that, a
  * full or unwritable log directory would go entirely unnoticed.
  */
-class LogWriter {
+final class LogWriter {
 	private static bool $failureLogged = false;
 
 	public static function write(
diff --git a/lib/Http/Client/Middleware/TransferStatsStore.php b/lib/Http/Client/Middleware/TransferStatsStore.php
index a2a5416..658f63d 100644
--- a/lib/Http/Client/Middleware/TransferStatsStore.php
+++ b/lib/Http/Client/Middleware/TransferStatsStore.php
@@ -15,7 +15,7 @@
  * a static array is sufficient; entries are removed as soon as the request's
  * log entry has been written or logging is skipped.
  */
-class TransferStatsStore {
+final class TransferStatsStore {
 	/** @var array<string, array> */
 	private static array $stats = [];