Java, JEE, Spring, C, Python, BASH, PHP, Ruby, Spring, CakePHP, ATtiny, ATmega, Arduino, Hadoop Map/Reduce, ZooKeeper, NiFi, MySQL, MariaDB, PostgreSQL, H2, Apache HTTP, Tomcat, Glassfish, Ant, Maven, Puppet, Capistrano, Debian, Ubuntu, RedHat, CentOS, Arch, HTML, CSS, JavaScript, Git, SVN, Photoshop, AfterFX, Reason, IDA, Eagle, and lots of related technologies / frameworks.