It was a long process with several interviews with different stakeholders. HR -> VP of Product -> Lead Developers -> BI -> VP of Engineering. There was no homework/challenge, but each interview was challenging with many questions about my experience and how I would approach/solve hypothetical situations. At the end of the process, I received a verbal offer, but a few days later while waiting to sign the contract, they informed me that my offer was under evaluation by the board. I had a further meeting to understand the situation, and then the offer was completely withdrawn using a generic "no thanks" email. Having the offer withdrawn was indeed a poor experience. Not counting that, everyone seemed very friendly and professional during the interviews, and in general the process moved swiftly.