Challenging interview but very efficient and transparent. I started with an introductory phone interview that got me to the technical interviews which lasted a little over an hour for each session. Overall, the process was smooth and took about 10 days to schedule and complete. Their interviewers are really sharp and know the domain really well. We covered challenging modeling and software questions. I've been in machine learning for more than 7 years and learned a few new things from the interviewers which is always nice.