Went through a phone screen, online coding problem (implementing a banking system), online behavioral interview, then an on-site four-hour interview with an API design (designing a Trello board), debugging a piece of broken code, an interview with a product manager, and a behavioral interview with tech leadership. Received feedback that I did poorly in the API design part of the interview so they were not able to extend me an offer. Recruiter was helpful in preparing and provided feedback after my interview. Wish it didn't require going all the way to a fourth round and taking time off to travel into the city to get rejected, especially when API design and whiteboarding can be done via a Zoom call as one of the earlier steps in the interview process.