diff --git a/composer.json b/composer.json
index f201f43..ebad5e6 100644
--- a/composer.json
+++ b/composer.json
@@ -23,6 +23,8 @@
 	"require-dev": {
 		"consistence/coding-standard": "2.2.1",
 		"jakub-onderka/php-parallel-lint": "0.9.2",
+		"matthiasnoback/symfony-config-test": "3.0.1",
+		"matthiasnoback/symfony-dependency-injection-test": "2.2.0",
 		"phpstan/phpstan-shim": "0.8.4",
 		"phpunit/phpunit": "6.4.3",
 		"satooshi/php-coveralls": "1.0.1"
@@ -44,6 +46,9 @@
 			]
 		}
 	},
+	"config": {
+		"sort-packages": true
+	},
 	"scripts": {
 		"build": [
 			"@composer validate --no-check-all",
diff --git a/tests/DependencyInjection/ConfigurationTest.php b/tests/DependencyInjection/ConfigurationTest.php
new file mode 100644
index 0000000..4735854
--- /dev/null
+++ b/tests/DependencyInjection/ConfigurationTest.php
@@ -0,0 +1,76 @@
+<?php
+
+declare(strict_types = 1);
+
+namespace Mhujer\JavaScriptErrorHandlerBundle\DependencyInjection;
+
+use Matthias\SymfonyConfigTest\PhpUnit\ConfigurationTestCaseTrait;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Config\Definition\ConfigurationInterface;
+
+class ConfigurationTest extends TestCase
+{
+
+	use ConfigurationTestCaseTrait;
+
+	public function testEmptyConfigurationIsValid(): void
+	{
+		$this->assertConfigurationIsValid(
+			[
+				[], // no values at all
+			]
+		);
+	}
+
+	public function testEnabledConfigurationIsValid(): void
+	{
+		$this->assertConfigurationIsValid(
+			[
+				[
+					'enabled' => true,
+				],
+			]
+		);
+	}
+
+	public function testDisabledConfigurationIsValid(): void
+	{
+		$this->assertConfigurationIsValid(
+			[
+				[
+					'enabled' => false,
+				],
+			]
+		);
+	}
+
+	public function testEnabledConfigurationIsValidXX(): void
+	{
+		$this->assertConfigurationIsInvalid(
+			[
+				[
+					'enabled' => 1,
+				],
+			],
+			'Invalid type for path "java_script_error_handler.enabled". Expected boolean, but got integer.'
+		);
+	}
+
+	public function testInvalidConfigurationIsInvalid(): void
+	{
+		$this->assertConfigurationIsInvalid(
+			[
+				[
+					'invalid_option' => 1,
+				],
+			],
+			'Unrecognized option "invalid_option" under "java_script_error_handler"'
+		);
+	}
+
+	protected function getConfiguration(): ConfigurationInterface
+	{
+		return new Configuration(true);
+	}
+
+}
diff --git a/tests/DependencyInjection/JavaScriptErrorHandlerExtensionTest.php b/tests/DependencyInjection/JavaScriptErrorHandlerExtensionTest.php
new file mode 100644
index 0000000..f497898
--- /dev/null
+++ b/tests/DependencyInjection/JavaScriptErrorHandlerExtensionTest.php
@@ -0,0 +1,62 @@
+<?php
+
+declare(strict_types = 1);
+
+namespace Mhujer\JavaScriptErrorHandlerBundle\DependencyInjection;
+
+use Matthias\SymfonyDependencyInjectionTest\PhpUnit\AbstractExtensionTestCase;
+use Mhujer\JavaScriptErrorHandlerBundle\EventListener\JsErrorToAlertListener;
+
+class JavaScriptErrorHandlerExtensionTest extends AbstractExtensionTestCase
+{
+
+	private const LISTENER_CLASS_NAME = JsErrorToAlertListener::class;
+
+	protected function getContainerExtensions()
+	{
+		return [
+			new JavaScriptErrorHandlerExtension(),
+		];
+	}
+
+	public function testListenerIsRegisteredInDebugMode(): void
+	{
+		$this->container->setParameter('kernel.debug', true);
+
+		$this->load();
+
+		$this->assertContainerBuilderHasService(self::LISTENER_CLASS_NAME);
+	}
+
+	public function testListenerIsNotRegisteredWithoutDebugMode(): void
+	{
+		$this->container->setParameter('kernel.debug', false);
+
+		$this->load();
+
+		$this->assertContainerBuilderNotHasService(self::LISTENER_CLASS_NAME);
+	}
+
+	public function testKernelDebugCanBeOverriddenToDisable(): void
+	{
+		$this->container->setParameter('kernel.debug', true);
+
+		$this->load([
+			'enabled' => false,
+		]);
+
+		$this->assertContainerBuilderNotHasService(self::LISTENER_CLASS_NAME);
+	}
+
+	public function testKernelDebugCanBeOverriddenToEnable(): void
+	{
+		$this->container->setParameter('kernel.debug', false);
+
+		$this->load([
+			'enabled' => true,
+		]);
+
+		$this->assertContainerBuilderHasService(self::LISTENER_CLASS_NAME);
+	}
+
+}