diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6e24837..e8700f7 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -25,6 +25,7 @@ jobs:
           - '8.0'
           - '8.1'
           - '8.2'
+          - '8.3'
         symfony:
           - '3.*'
           - '4.*'
@@ -38,6 +39,7 @@ jobs:
           - { php: '8.0', symfony: '3.*' }
           - { php: '8.1', symfony: '3.*' }
           - { php: '8.2', symfony: '3.*' }
+          - { php: '8.3', symfony: '3.*' }
           - { php: '7.1', symfony: '5.*' }
           - { php: '7.1', symfony: '6.*' }
           - { php: '7.2', symfony: '6.*' }
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5f5ed61..7f051b5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,13 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [1.8.1]
+### Added
+- `void` typehint to `PayseraApiBundle::build` method to fix the deprecation message
+- PHP 8.3 to CI
+### Fixed
+- `Call to a member function getClassAnnotations() on null` error in `RoutingAttributeLoader` on Symfony 6
+
 ## [1.8.0]
 ### Added
 - Support for PHP 8 attributes
diff --git a/src/Listener/RestResponseListener.php b/src/Listener/RestResponseListener.php
index 9aca71e..bd5239e 100644
--- a/src/Listener/RestResponseListener.php
+++ b/src/Listener/RestResponseListener.php
@@ -65,7 +65,7 @@ private function normalizeResult(Request $request, RestRequestOptions $options,
     {
         $includedFields = [];
         $fields = $request->query->get('fields');
-        if ($fields !== null && is_string($fields) && $fields !== '') {
+        if (is_string($fields) && $fields !== '') {
             $includedFields = explode(',', $fields);
         }
 
diff --git a/src/PayseraApiBundle.php b/src/PayseraApiBundle.php
index 551138e..7be4b1e 100644
--- a/src/PayseraApiBundle.php
+++ b/src/PayseraApiBundle.php
@@ -9,7 +9,7 @@
 
 class PayseraApiBundle extends Bundle
 {
-    public function build(ContainerBuilder $container)
+    public function build(ContainerBuilder $container): void
     {
         parent::build($container);
 
diff --git a/src/Service/RoutingLoader/RoutingAttributeLoader.php b/src/Service/RoutingLoader/RoutingAttributeLoader.php
index 87eaae8..955f27d 100644
--- a/src/Service/RoutingLoader/RoutingAttributeLoader.php
+++ b/src/Service/RoutingLoader/RoutingAttributeLoader.php
@@ -61,6 +61,10 @@ protected function configureRoute(
 
     private function loadAnnotations(Route $route, ReflectionClass $class, ReflectionMethod $method): void
     {
+        if (!isset($this->reader)) {
+            return;
+        }
+
         $annotations = [];
         foreach ($this->reader->getClassAnnotations($class) as $annotation) {
             if ($annotation instanceof RestAnnotationInterface) {