diff --git a/composer.json b/composer.json
index 31a950c8d..aed6a3674 100644
--- a/composer.json
+++ b/composer.json
@@ -38,7 +38,7 @@
         "symfony/error-handler": "^7.3.2 || ^8.0",
         "symfony/filesystem": "^5.0 || ^6.0 || ^7.0 || ^8.0",
         "symfony/finder": "^4.4 || ^5.0 || ^6.0 || ^7.0 || ^8.0",
-        "symfony/framework-bundle": "^5.4.45 || ^6.4.13 || ^7.1.6",
+        "symfony/framework-bundle": "^5.4.45 || ^6.4.13 || ^7.1.6 || ^8.0",
         "symfony/http-kernel": "^4.4 || ^5.0 || ^6.0 || ^7.0 || ^8.0",
         "symfony/phpunit-bridge": "^7.3.2 || ^8.0",
         "symfony/polyfill-uuid": "^1.13.1",
diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index c157cd326..d32950323 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -14,3 +14,8 @@ parameters:
         - identifier: missingType.iterableValue
         - '#PHPDoc tag @throws with type Psr\\Cache\\CacheException is not subtype of Throwable$#'
         - '#^Dead catch - JsonException is never thrown in the try block\.$#'
+        # BaseBundle conditionally extends the modern AbstractBundle, which only exists on Symfony 8.1+.
+        # On older Symfony that parent is unknown, so PHPStan cannot resolve the inherited parent::build().
+        -
+            message: '#^Call to an undefined static method AsyncAws\\Symfony\\Bundle\\BaseBundle::build\(\)\.$#'
+            path: src/Integration/Symfony/Bundle/src/AsyncAwsBundle.php
diff --git a/src/Integration/Symfony/Bundle/CHANGELOG.md b/src/Integration/Symfony/Bundle/CHANGELOG.md
index f9dc66063..323475b5a 100644
--- a/src/Integration/Symfony/Bundle/CHANGELOG.md
+++ b/src/Integration/Symfony/Bundle/CHANGELOG.md
@@ -4,6 +4,7 @@
 
 ### Fixed
 
+- Fixed deprecation warnings on Symfony 8.1
 - Fixed tests on Symfony 8.1
 
 ## 1.17.0
diff --git a/src/Integration/Symfony/Bundle/src/AsyncAwsBundle.php b/src/Integration/Symfony/Bundle/src/AsyncAwsBundle.php
index 226f9ef56..edaf65840 100644
--- a/src/Integration/Symfony/Bundle/src/AsyncAwsBundle.php
+++ b/src/Integration/Symfony/Bundle/src/AsyncAwsBundle.php
@@ -4,16 +4,46 @@
 
 namespace AsyncAws\Symfony\Bundle;
 
+use AsyncAws\Symfony\Bundle\DependencyInjection\AsyncAwsExtension;
 use AsyncAws\Symfony\Bundle\DependencyInjection\Compiler\InjectCasterPass;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Extension\ExtensionInterface;
+use Symfony\Component\DependencyInjection\Kernel\AbstractBundle;
 use Symfony\Component\HttpKernel\Bundle\Bundle;
 
-class AsyncAwsBundle extends Bundle
+if (class_exists(AbstractBundle::class)) {
+    /**
+     * @internal
+     */
+    abstract class BaseBundle extends AbstractBundle
+    {
+    }
+} else {
+    /**
+     * @internal
+     */
+    abstract class BaseBundle extends Bundle
+    {
+    }
+}
+
+class AsyncAwsBundle extends BaseBundle
 {
+    private ?ExtensionInterface $asyncAwsExtension = null;
+
     public function build(ContainerBuilder $container): void
     {
         parent::build($container);
 
         $container->addCompilerPass(new InjectCasterPass());
     }
+
+    /**
+     * Return the conventional extension explicitly: the modern AbstractBundle base class would
+     * otherwise auto-register an empty BundleExtension and ignore AsyncAwsExtension.
+     */
+    public function getContainerExtension(): ?ExtensionInterface
+    {
+        return $this->asyncAwsExtension ??= new AsyncAwsExtension();
+    }
 }