Backend: JS (Node.js), PHP(CodeIgniter, Zend, Laravel, Yii), ... DB: MySql, Posgres, Blockchain (LevelDB), Firebird, Redis, MongoDB , ... Frontend: HTML, JS (VueJS), CSS, (SCSS, LESS), CDN, ... Instruments: Mikrotik, Unifi, Cisco, Ubuntu, Proxmox, MASS, VMVare, Kubernetes, Google Cloud, AWS, IBM Cloud, GitHub, CloudFlare, ZeroTier, ...