I don't usually leave reviews on Glassdoor, but I felt the need to leave one here because I believe the current reviews are a little too negative. I think each team has some freedom to design their own interview process. In the team that I applied for, the normal interview process follows something like this: 1. Interview with recruiter -> 2. Interview with team manager -> 3. Non-technical interview with technical people -> Home assignment -> 4. Technical interview -> 5. Cultural Interview with Director of People -> 6. Short meeting with CEO.
It IS a long process, and in my case, it was even longer as they decided to add an additional technical interview to be able to have more time to discuss machine learning questions. The people interviewing me were very nice and very intelligent, and I got the impression that the additional interview they added was custom-made to assess my particular expertise (although I might be wrong). I think it's a nice feature that the company is flexible and that the people interviewing candidates have the freedom to make adjustments if necessary. I can see how this flexibility and freedom may sometimes lead to "messy processes", but I think it's worth it as it has many other advantages. The company seems to be always ready to adapt, improve, and take feedback seriously. I also want to mention that I was pleasantly surprised to find that the Director of People was an awesome mathematician, very sincere, straightforward and open minded (not at all a standard HR person). Everyone I spoke with was extremely nice, smart and honest and I had an overall very positive experience during the whole interview process.