diff --git a/src/DependencyInjection/Compiler/LocatorRegistrationPass.php b/src/DependencyInjection/Compiler/LocatorRegistrationPass.php
index 5b10ad39..7b328808 100644
--- a/src/DependencyInjection/Compiler/LocatorRegistrationPass.php
+++ b/src/DependencyInjection/Compiler/LocatorRegistrationPass.php
@@ -33,7 +33,7 @@ class LocatorRegistrationPass implements CompilerPassInterface
     /**
      * {@inheritdoc}
      */
-    public function process(ContainerBuilder $container)
+    public function process(ContainerBuilder $container): void
     {
         $container->getDefinition(Instantiator::class)
             ->setArguments([[
diff --git a/src/DependencyInjection/DataTablesExtension.php b/src/DependencyInjection/DataTablesExtension.php
index 93f80368..c826905f 100644
--- a/src/DependencyInjection/DataTablesExtension.php
+++ b/src/DependencyInjection/DataTablesExtension.php
@@ -32,7 +32,7 @@ class DataTablesExtension extends Extension
     /**
      * {@inheritdoc}
      */
-    public function load(array $configs, ContainerBuilder $container)
+    public function load(array $configs, ContainerBuilder $container): void
     {
         $configuration = new Configuration();
         $config = $this->processConfiguration($configuration, $configs);