The first interview was a phone interview. The questions were standard interview questions - not easy but not impossible either. The on-site was 2-3 hours with a handful of different engineers. I had a very enjoyable time during the onsite. The first question took me a while to solve, but they didn't seem to mind as long as I was talking through my response and explaining my thought process. Then they asked me a question that simplified into a BFS implementation. I came away from the interview liking the company a lot, and then received an offer. I told them I would want a little bit of time to hear back from other companies before accepting the offer - they indicated that this was fine. A few days later, they rescinded my offer with no warning, having given the position to someone else. This was completely unprofessional and soured me on the company.