I have been a full time Drupal professional since 2007.

My aim is to undestand all technical details and workings of every site/project I'm involved in. I like, or rather need to understand how things work, which means my Drupal related "feelings" are based on hard fact instead of guessing.. Mostly. There is also the feeling part :)

Apart from core and contrib, my Drupal knowledge it not just limited to Drupal-code, but the whole technical process including
PHP, MySQL, nginx, Varnish, HTTP-protocol. What I like most is fixing performance bottlenecks.

All this has led me to become especially interested in performance optimization, as it requires a deep understanding on everything that is going on, and the motivation to make things work as efficiently as possible.