I applied online and was emailed by a recruiter the next day. They asked me to pick a time for the first phone interview (all of which are technical). This interview didn't involve programming, but some questions about UNIX and my personal projects. The interviews moved very quickly, the recruiter was always in contact the next day or so. Both the second and the third interview involved coding on a shared editor. For the second one I had to design an algorithm for a non-surprising string related interview question, which has an obvious solution in O(n^2) time, but requires hashing for O(n). The third one required smart usage of two different data structures for the same data in order to get the benefits of both. After the phone interviews, I was asked for a date to go to their NYC office.
While the phone interview questions had definite answers, two of the problems for the on-site interviews were open ended and seemed to serve the purpose of letting them see you tackle a problem when you don't know where to begin right off the bat. Since I have no prior functional programming experience, I was recommended to study some OCaml before coming over. However, to my (positive) surprise, for the interview that required me to use it, one of the interviewers brought in a cheat-sheet of OCaml basics and went over it. I was then asked to implement a function which was of appropriate difficulty for a beginner. After I had my solution up on the board, the interviewer put up a shorter solution and asked me which one is better and why. They both had the same time complexity, but it turned out that they actually use the solution I came up with, because it does not do any computations after returning from a recursive call, in which case the compiler knows not to allocate additional stack frames.
All of the interviewers were kind and patient, had a sense of humor, and were extremely intelligent (it seemed some of them could've become supervillains but opted for arbitrage). Their office is very nice, reminds me of something a well funded silicon valley company would go for.