It was called a hackathon, but was probably more a CTF on a distributed TOR network. Organized by Dutch tax police (FIOD) for students. Finished it single-handledly in 18 hours, in front of several teams consisting of 6 people. Immediately got a job offer, but declined since I still wanted to do a master's :)

Did doing the Master's help? Also, why/how is "lose the ego" relevant here?

@asgs still doing it! It's loads of fun and learning everyday. So no regrets :)

Concerning "lose the ego": anyone with basic programming, networking and cli skills could've cracked the challenges within the time limit. IMO it sounds like it's a big deal, but it really wasn't. Every team finished in time.
Dunno, guess I just don't like parading in front of everyone haha