I tend to give about one technical interview for this position per week. I won't give you the interview questions but I will tell you this. Come to each interview prepared by studying topics in compute science, algorithms, and compute architecture. We are mostly interested in your ability to solve a challenging problem and adapt to new information. Good luck.

Tl;dr: Long interview process, very intellectually stimulating discussions, no offer due to internal restructuring. The interviewers were experts in the various skill areas required for the job, and they asked abstract, open questions. Each interviewer seemed highly qualified. Each interview was therefore an interesting discussion. At the end, the recruiter informed me that due to some internal restructuring, the position had to be cancelled.