Fatal error: Uncaught Error: Interface 'Symfony\Component\Serializer\SerializerInterface' not found in /home/almasai/www/people/_old_site/vendor/symfony/src/Symfony/Component/Serializer/Serializer.php:35 Stack trace: #0 {main} thrown in /home/almasai/www/people/_old_site/vendor/symfony/src/Symfony/Component/Serializer/Serializer.php on line 35