diff --git a/src/Model/LatLongModel.php b/src/Model/LatLongModel.php
index 4c0cfef..88bc3c9 100644
--- a/src/Model/LatLongModel.php
+++ b/src/Model/LatLongModel.php
@@ -9,7 +9,7 @@ namespace Pcm\GeocodeBundle\Model;
  *
  * @package Pcm\GeocodeBundle
  */
-class LatLongModel
+final class LatLongModel
 {
     public function __construct(private float $latitude, private float $longitude) {}
 
diff --git a/src/PcmGeocodeBundle.php b/src/PcmGeocodeBundle.php
index a2f45a5..f700023 100644
--- a/src/PcmGeocodeBundle.php
+++ b/src/PcmGeocodeBundle.php
@@ -10,7 +10,7 @@ use Symfony\Component\DependencyInjection\Loader\Configurator\ContainerConfigura
 use Symfony\Component\DependencyInjection\Loader\YamlFileLoader;
 use Symfony\Component\HttpKernel\Bundle\AbstractBundle;
 
-class PcmGeocodeBundle extends AbstractBundle {
+final class PcmGeocodeBundle extends AbstractBundle {
     public function loadExtension(array $config, ContainerConfigurator $container, ContainerBuilder $builder): void
     {
         $loader = new YamlFileLoader($builder, new FileLocator(__DIR__.'/../config/'));
diff --git a/src/Service/Geocoder.php b/src/Service/Geocoder.php
index b3ec623..12e7248 100644
--- a/src/Service/Geocoder.php
+++ b/src/Service/Geocoder.php
@@ -8,7 +8,7 @@ use Pcm\GeocodeBundle\Model\LatLongModel;
 use Symfony\Contracts\HttpClient\HttpClientInterface;
 use Symfony\Contracts\HttpClient\ResponseInterface;
 
-class Geocoder
+final class Geocoder
 {
     private const string API_URL = "https://nominatim.openstreetmap.org/search";
 
diff --git a/tests/AppKernel.php b/tests/AppKernel.php
index 2d55c2d..de5283f 100644
--- a/tests/AppKernel.php
+++ b/tests/AppKernel.php
@@ -9,7 +9,7 @@ use Symfony\Bundle\FrameworkBundle\FrameworkBundle;
 use Symfony\Component\Config\Loader\LoaderInterface;
 use Symfony\Component\HttpKernel\Kernel;
 
-class AppKernel extends Kernel
+final class AppKernel extends Kernel
 {
     /**
      * @return array
@@ -30,3 +30,4 @@ class AppKernel extends Kernel
         $loader->load(__DIR__.'/config_'.$this->getEnvironment().'.yml');
     }
 }
+
diff --git a/tests/Service/GeocodeTest.php b/tests/Service/GeocodeTest.php
index 073f0b8..a6fa965 100644
--- a/tests/Service/GeocodeTest.php
+++ b/tests/Service/GeocodeTest.php
@@ -14,7 +14,7 @@ use Symfony\Bundle\FrameworkBundle\Test\KernelTestCase;
 /**
  * We sleep 1 second after API calls to prevent breaking the API T&Cs.
  */
-class GeocodeTest extends KernelTestCase
+final class GeocodeTest extends KernelTestCase
 {
     // Buckingham Palace
     private const string POSTCODE = 'SW1A 1AA';
diff --git a/tests/Trait/MappableTraitTest.php b/tests/Trait/MappableTraitTest.php
index dd07c79..49a6436 100644
--- a/tests/Trait/MappableTraitTest.php
+++ b/tests/Trait/MappableTraitTest.php
@@ -8,7 +8,7 @@ use Pcm\GeocodeBundle\Entity\Interface\MappableInterface;
 use Pcm\GeocodeBundle\Entity\Trait\MappableTrait;
 use PHPUnit\Framework\TestCase;
 
-class MappableTraitTest extends TestCase
+final class MappableTraitTest extends TestCase
 {
     private const float COORD = 123.456;