Firstly, I just have to say that the Amazon recruiters were amazing. I'm only going to say enough to give y'all the best heads up without violating my NDA.
The interview process is pretty standard. The recruiter reached out, described the position, planned some dates. I'm sure it changes from program to program and team to team but expect to receive a phone screen, an online coding challenge (or two), and if all goes well, an in-house interview.
I interviewed for the Amazon Alexa team at their Seattle office on 7th Ave. They provided a plane flight, hotel stay, and a little card to cover travel expenses. It was really more than I expected and incredibly nice of Amazon. They could have done a more frugal job and I would've still been satisfied.
Practice your soft questions, it's much more important than you think and there will be a lot more than you want. This isn't a secret. Your recruiters will tell you this and you should listen. Amazon is a client facing business and it only makes sense. Furthermore, you will be grilled on soft questions and immediately start coding and it's a seriously tough transition. You've been warned.
Things felt rough, those interviews are never designed to make you feel good. I consider myself a moderately okay coder with decent people skills. But it must've went alright because I received a call roughly 3 days later with an offer (Alexa was in a hiring push so don't be worried if it takes more than 3 days).
I didn't expect an answer so soon, that's a very unusual turn-around time and I had other interviews the following week. The recruiters were flexible and gave me an week extension to finish my interviews and work on a decision on top of the original 10 day offer window.
I ended up taking a different offer with a different company but Amazon provided a great offer above market value, the recruiters were the best I've dealt with, the short trip to Seattle really made me fall for the city.
There are a few unfair precepts about Amazon but all I saw were small highly productive teams with code and hiring autonomy. It was a positive, supportive, and welcoming experience. Other companies would do well to imitate their process. It was really tough to go elsewhere (more about family and training than Amazon itself) and I'll reach out again in the future based on my experience.