Without going into specifics due to NDA contract, I will try to be as specific as I can to provide some useful feedback. I was interviewing for a (greater than) senior engineer position (staff in their org chart). Good experience overall. Work environment seemed friendly and not as hectic as a regular startup would be. At this point the company is already large enough that I cannot consider it a startup. Job security seems good as they are privately held with Series E funding. Engineers seemed competent and relatively experienced. You will be expected to act on many parts of the system. Tips: 1. Brush up on system design. The interviewer I had was very good in drilling down into details and questioning your every decision. Make sure you can come up with justifications for everything you design. 2. Some SQL understanding would be great. I wasn't comfortable with writing queries on the fly but the interviewer was helpful enough to give me tips.