I build a lot of amazing things in 2009-2014 while I was in Facebook, some of them are:
1) Fraud system that was able to handle chargebacks below 1% for VIRTUAL goods!
2) Facebook News Feed Ads, Create Flow
3) Instagram Ads
Before Facebook, I had an outsourcing start up which was boring and nothing to be proud about, but it was good management experience.
I leave in California, USA and Kiev, Ukraine 50/50