Knowledge about professional software engineering e.g. SOLID-principles, Clean Code, Separation of Concerns;
Working experience with standard frameworks like Zend, Symfony, Laravel or others;
Backend: PHP 7, PostgreSQL, Redis, ElasticSearch, Twig, Silex, Composer, Git;
Frontend: Javascript, Webpack, NPM;
System: Vagrant, Saltstack;
E-Commerce experience with shop systems like Oxid, Magento, Hybris or similar.