My journey started when I was still at school and during a weekend I wrote a prototype called JSPP ( blog.vjeux.com/2011/javascript/jspp-morph-cpp-int… ), a way to exploit C++0x and macros in order to write C++ code that looks and execute in the same way as JavaScript. In practice it is useless but it got to Hacker News and someone from Facebook reached out to me to figure out if I was interested in joining the company. At first I thought it was a prank, but I'm so glad it wasn't! After a few phone interviews, they bought me a plane ticket to California and booked an awesome hotel so that I could do a day of onsite interviews. Even though most people seem to hate interviews, I actually very enjoyed the process, it's not often that you get to be intensively challenged for an entire day by really good people. I got an offer and started 6 months later when I finished school.
When you join Facebook, you're not allocated to any team during the first month and a half, it's a period called "Bootcamp", where you have a mix of classes to teach you about all the internals of Facebook codebase and infrastructure and time to work on real problems. Once I cleared the first few small tasks assigned by my mentor, I looked at all of them and there was one created by someone named Pete Hunt that piqued my interested that looked along those lines: "We know where faces are in photos, it would be interesting to use this data to improve the tagging experience". And little did I know, I managed to ship a first version of the feature within the first month and it non trivially increased a core Facebook metric! When out of bootcamp, I then joined the photos team full time :)