diff --git a/composer.json b/composer.json
index a46ca79..de21c89 100644
--- a/composer.json
+++ b/composer.json
@@ -1,4 +1,3 @@
-
 {
     "name": "m6web/monolog-extra-bundle",
     "type": "symfony-bundle",
@@ -16,11 +15,11 @@
     "require": {
         "php": ">=5.6",
         "symfony/monolog-bundle": "~2.0 || ~3.0",
-        "symfony/expression-language": "~2.3 || ~3.0"
+        "symfony/expression-language": "~2.3 || ~3.0 || ~4.0"
     },
     "require-dev": {
         "atoum/atoum": "~3.0",
-        "symfony/yaml": "~2.3 || ~3.0"
+        "symfony/yaml": "~2.3 || ~3.0 || ~4.0"
     },
     "autoload": {
         "psr-0": { "": "src/" }
diff --git a/src/M6Web/Bundle/MonologExtraBundle/DependencyInjection/M6WebMonologExtraExtension.php b/src/M6Web/Bundle/MonologExtraBundle/DependencyInjection/M6WebMonologExtraExtension.php
index c180d07..2069dc7 100644
--- a/src/M6Web/Bundle/MonologExtraBundle/DependencyInjection/M6WebMonologExtraExtension.php
+++ b/src/M6Web/Bundle/MonologExtraBundle/DependencyInjection/M6WebMonologExtraExtension.php
@@ -38,7 +38,7 @@ public function load(array $configs, ContainerBuilder $container)
                     $tagOptions['handler'] = $processor['handler'];
                 }
 
-                $definition = clone $container->getDefinition(sprintf('%s.processor.%s', $alias, $processor['type']));
+                $definition = clone $container->getDefinition(sprintf('%s.processor.%s', $alias, lcfirst($processor['type'])));
                 $definition->setAbstract(false);
                 $definition->addtag('monolog.processor', $tagOptions);