I made it to the third round of interviewing.
The first interview was a phone screen, where I described my work experience and learned about the company. The second interview, I met with the CEO and was asked about APIs, PR comments, and how I would design a system (pseudo code okay). The third interview was approximately 4 hours. I met with other members of the team, including one of the founders. The last ~ 2.5 hours I met with the CEO/co-founder for a coding exercise.
The team was amazing and I appreciated that the coding exercises were structured so that the interviewee could demonstrate whether s/he had the working knowledge necessary for the position (rather than asking the interviewee to solve abstract coding challenges that didn't necessarily have anything to do with the job position).
I know we're supposed to give pros and cons but I honestly can't think of any cons. It was a great experience, all around.