diff --git a/.travis.yml b/.travis.yml
index 1254101..0147f27 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,6 +4,7 @@ php:
   - '7.1'
   - '7.2'
   - '7.3'
+  - '7.4'
 
 env:
   global:
diff --git a/composer.json b/composer.json
index 66660c6..f789859 100644
--- a/composer.json
+++ b/composer.json
@@ -30,9 +30,9 @@
   },
   "require": {
     "php": ">=7.1",
-    "yoanm/jsonrpc-server-doc-sdk": "^0.1",
-    "yoanm/jsonrpc-http-server-swagger-doc-sdk": "^0.1",
-    "yoanm/symfony-jsonrpc-http-server-doc": "^0.1",
+    "yoanm/jsonrpc-server-doc-sdk": "^0.2",
+    "yoanm/jsonrpc-http-server-swagger-doc-sdk": "^0.2",
+    "yoanm/symfony-jsonrpc-http-server-doc": "^0.2",
     "symfony/http-kernel": "^3.0 || ^4.0",
     "symfony/dependency-injection": "^3.0 || ^4.0"
   },
@@ -40,7 +40,7 @@
     "behat/behat": "~3.0",
     "squizlabs/php_codesniffer": "3.*",
     "phpunit/phpunit": "^7.0 || ^8.0",
-    "matthiasnoback/symfony-dependency-injection-test": "^2.0 || ^3.0",
+    "matthiasnoback/symfony-dependency-injection-test": "^3.0 || ^4.0",
     "matthiasnoback/symfony-config-test": "^3.0 || ^4.0",
     "symfony/framework-bundle": "^3.0 || ^4.0",
     "yoanm/php-unit-extended": "~1.0"
diff --git a/tests/Common/DependencyInjection/AbstractTestClass.php b/tests/Common/DependencyInjection/AbstractTestClass.php
index e048c45..4fb1f96 100644
--- a/tests/Common/DependencyInjection/AbstractTestClass.php
+++ b/tests/Common/DependencyInjection/AbstractTestClass.php
@@ -19,7 +19,7 @@ abstract class AbstractTestClass extends AbstractExtensionTestCase
     /**
      * {@inheritdoc}
      */
-    protected function getContainerExtensions()
+    protected function getContainerExtensions(): array
     {
         return [
             new JsonRpcHttpServerDocExtension(),
@@ -27,7 +27,7 @@ protected function getContainerExtensions()
         ];
     }
 
-    protected function load(array $configurationValues = [])
+    protected function loadContainer(array $configurationValues = []): void
     {
         $eventDispatcherDefinition = new Definition(EventDispatcher::class);
         $this->setDefinition('event_dispatcher', $eventDispatcherDefinition);
diff --git a/tests/Functional/DependencyInjection/ConfigFilesTest.php b/tests/Functional/DependencyInjection/ConfigFilesTest.php
index 1420b82..cac67bc 100644
--- a/tests/Functional/DependencyInjection/ConfigFilesTest.php
+++ b/tests/Functional/DependencyInjection/ConfigFilesTest.php
@@ -33,7 +33,7 @@ class ConfigFilesTest extends AbstractTestClass
      */
     public function testShouldHaveService($serviceId, $expectedClassName, $public)
     {
-        $this->load();
+        $this->loadContainer();
 
         $this->assertContainerBuilderHasService($serviceId, $expectedClassName);
         if (true === $public) {
@@ -44,7 +44,7 @@ public function testShouldHaveService($serviceId, $expectedClassName, $public)
 
     public function testDocProviderShouldHaveDocProviderTag()
     {
-        $this->load();
+        $this->loadContainer();
 
         // From yoanm/symfony-jsonrpc-http-server
         $this->assertContainerBuilderHasServiceDefinitionWithTag(
diff --git a/tests/Functional/DependencyInjection/JsonRpcHttpServerSwaggerDocExtensionTest.php b/tests/Functional/DependencyInjection/JsonRpcHttpServerSwaggerDocExtensionTest.php
index 4fd5402..00ca9a7 100644
--- a/tests/Functional/DependencyInjection/JsonRpcHttpServerSwaggerDocExtensionTest.php
+++ b/tests/Functional/DependencyInjection/JsonRpcHttpServerSwaggerDocExtensionTest.php
@@ -11,7 +11,7 @@ class JsonRpcHttpServerSwaggerDocExtensionTest extends AbstractTestClass
 {
     public function testShouldBeLoadable()
     {
-        $this->load();
+        $this->loadContainer();
 
         $this->assertDocProviderIsLoadable();
     }
diff --git a/tests/Functional/Event/SwaggerDocCreatedEventTest.php b/tests/Functional/Event/SwaggerDocCreatedEventTest.php
index 58891c2..2d34afa 100644
--- a/tests/Functional/Event/SwaggerDocCreatedEventTest.php
+++ b/tests/Functional/Event/SwaggerDocCreatedEventTest.php
@@ -19,7 +19,7 @@ class SwaggerDocCreatedEventTest extends TestCase
     /** @var HttpServerDoc|ObjectProphecy */
     private $serverDoc;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         $this->swaggerDoc = ['swaggerDoc'];
         $this->serverDoc = $this->prophesize(HttpServerDoc::class);
diff --git a/tests/Functional/Provider/DocProviderTest.php b/tests/Functional/Provider/DocProviderTest.php
index 0daa786..7e74da4 100644
--- a/tests/Functional/Provider/DocProviderTest.php
+++ b/tests/Functional/Provider/DocProviderTest.php
@@ -26,7 +26,7 @@ class DocProviderTest extends TestCase
     /** @var DocNormalizer|ObjectProphecy */
     private $docNormalizer;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         $this->dispatcher = $this->prophesize(EventDispatcherInterface::class);
         $this->httpServerDocCreator = $this->prophesize(HttpServerDocCreator::class);