I had 2 phone coding interviews followed by a 2-day onsite where you get to work on a real project in the actual codebase. It's probably going to be a feature they've already started implementing, or have even already shipped. You get support as if you were working full-time, and it's a great to way to see if you'd like to work there.

Recruiter call, then HackerRank technical interview with an engineer on the line. It was a mostly practical interview question. The interview was helpful when it came to syntax issues - he stated multiple times that syntax was not the point of the interview.