There were 4 rounds. First was an online test on javascript(they mainly use javascript). Second was a javascript workshop. Not your typical run of the mill javascript workshop but I had a lot of fun. Third interview was an online meeting with a top level engineer. Had a few technical questions. Final interview was a team meeting. Had a lot more technical questions.
Questions were mostly related to AWS. I did not have an exact working knowledge on everything AWS but I did manage to get through it.
Interview process took over a month, which was frustrating but I am assuming it was probably because the team was busy on other things and there were a bunch of holidays inbetween.