public function process(ContainerBuilder $container)
    {
        $registryDefinition = $container->getDefinition('spray_serializer.serializer_registry');
        $tagged = $container->findTaggedServiceIds('spray_serializer');
        
        foreach ($tagged as $id => $tags) {
            foreach ($tags as $attr) {
                $registryDefinition->addMethodCall('add', array(
                    new Reference($id)
                ));
            }
        }
    }