I was contacted by a recruiting contact from HR. From there I was passed off to another contact who scheduled two back to back, 45 minute coding interviews. The first interviewer was very pleasant. After initially asking a question on which I fumbled, we spent the remaining time working on one question. The question itself wasn't terribly difficult, but it was intentionally ambiguous, to make sure I asked the right questions. After clearing up details we discussed optimizations, etc. This is probably the part of the interview that was most enjoyable as it didn't really feel like I was getting grilled. It felt as if we were discussing a problem and different approaches we could take. The second interviewer had a bit of an accent and seemed a bit less engaged/helpful. Also, the questions he asked were significantly tougher. All in all the process went very smoothly.