Two sessions with System Design. The rest of the questions were based on the Amazon Leadership Principals (many sources online with details about these questions). Plus had to submit a written essay before the in-person interview.

I first had two phone interviews with the company, which were very friendly. They were trying to find out what I was interested in doing and see if I might be a fit for one of their positions. After they decided I was a good fit, they invited me to come in onsite. The onsite was also very good, albeit a compacted schedule of 6 back-to-back 45-minute long interviews. They asked me some technical questions on coding and lots of situation-behavioral questions. Everyone was very nice and professional throughout