Python: native, Django
PHP: native, Yii
JS: native, ExtJS, jQuery, OpenLayers, Leaflet
DB: PostgreSQL, MySQL
NoSQL: Redis, Memcached
Page layout: HTML, CSS
OS: Ubuntu, Windows
WS: Nginx, Apache
VCS: GIt, Mercurial
Monitoring: ZABBIX
Tracker: Redmine
Error tracker: Sentry
Continuous delivery: GitLab, Ansible, Chef