diff --git a/src/DependencyInjection/Configuration.php b/src/DependencyInjection/Configuration.php
index 4426feaa..ae0ac4ac 100644
--- a/src/DependencyInjection/Configuration.php
+++ b/src/DependencyInjection/Configuration.php
@@ -9,7 +9,7 @@
 
 class Configuration implements ConfigurationInterface
 {
-    public function getConfigTreeBuilder()
+    public function getConfigTreeBuilder(): TreeBuilder
     {
         $treeBuilder = new TreeBuilder('oneup_uploader');
         $rootNode = $treeBuilder->getRootNode();
diff --git a/tests/App/Kernel.php b/tests/App/Kernel.php
index 3b728261..1a15234d 100644
--- a/tests/App/Kernel.php
+++ b/tests/App/Kernel.php
@@ -11,7 +11,7 @@
 
 class Kernel extends BaseKernel
 {
-    public function registerBundles()
+    public function registerBundles(): iterable
     {
         $bundles = [
             new FrameworkBundle(),
@@ -30,7 +30,7 @@ public function registerContainerConfiguration(LoaderInterface $loader): void
         $loader->load($this->getProjectDir() . '/config/config.yml');
     }
 
-    public function getProjectDir()
+    public function getProjectDir(): string
     {
         return __DIR__;
     }