The first part consisted of a preliminary phone screen with an HR representative and a member of the team to which you're applying, asking basic questions about your current role (if you have one) and what you're looking for at Amazon.
If you pass the screening, a several-hour interview "loop" is scheduled shortly thereafter. Before the interview, you must complete a writing sample which assess if you can follow directions, interpret ambiguities, and complete tasks in a certain amount of time. The interview consists of five, 45-minute conversations with various employees in different roles on the prospective team for which you are applying. One of those interviewers is the hiring manager for the role and another is a "bar-raiser" who is an experienced Amazon interviewer and knows what to listen for.
After the interview you will receive an offer or not within five business days, no later.