Bar none, the most odious, arduous and asinine interview process I've had the misfortune of suffering through. A few phone screens, followed by a coding interview, followed by an onsite.
The onsite interview is borderline torture, 6+ hours and it's just one interviewer after the next for that whole time. Your jaw will ache from all the talking and the uncomfortable chairs only add to your agony. They don't even have the decency to leave you alone for lunch, they'll take you out from lunch and the people going with you (I daresay escorting you) will tell you that the meal is not part of the interview and just a time for you to ask them general questions, this is a bald-faced lie. They are judging you the entire time.
All the coding questions are done in HackerRank and in spite of the fact that you never actually run the code your answers must be in a programming language and be syntactically correct. Furthermore, they send you a "How to ace our programming interview" guide ahead of time which is just a tacit admission that their interviewing method is deeply flawed or they seriously expect you to study every day before coming into work.
They offer high pay but just save yourself the pain and misery and look elsewhere.