Andresen worked on several different software projects before joining Bitcoin in 2010. He worked on the VRML specification at Silicon Graphics (SGI).
Satoshi Nakamoto directly appointed Andresen to head Bitcoin development when he departed the project. Andresen led the Bitcoin Core development team for several years until he departed as well. His last commit was in early 2016.
Today he leads the Bitcoin Foundation and is often a demanded speaker at Bitcoin and cryptocurrency related events.
Photo Credit: Stephen McCarthy / SPORTSFILE / Web Summit