I was first put in touch with a recruiter in late December, and the process took roughly 2 months -- primarily as my schedule was in flux, for which they were extremely accommodating. My recruiter (Dani) was an absolute saint throughout the process and very flexible on the interview timeline and the discussion of start date. As far as the interview process, it follows the generic interview format you'll see at most major tech companies. Intro call, tech screen, full-day onsite (algorithms, system design).
Also, the CEO popped his head in and introduced himself during the interview. While this shouldn't be why you accept the offer, it was a strong indication to me that while Compass may not be a software company in the strictest terms, technology and maintaining a strong engineering culture is not an after thought. A week into the job and I'd double down on this sentiment.