After arriving I sat down in a conference room with two developers who asked me a series of standard technical questions about computer science and my self professed strengths in Python and JavaScript, nothing on the white board. After the developers left the CTO introduced himself and asked me more general interview questions regarding my past work experience, how I dealt with difficult personalities, etc. After that I sat with a third developer for an hour long pair programming exercise. There were no prepared problem, together we troubleshooted an actual bug they were experiencing at the time. It was slightly difficult to provide input on a new code base in an hour but dev I was paired with was helpful and pleasant to work with.
All in all it was a pretty standard experience, although the pair programming section could have been better organised.