First, there was a video call with the CTO, 30 minutes. Then, about a week later, 2 more video interviews back-to-back, 45 minutes each. Then, about a week after that, another 2 interviews back to back, an hour each, this time onsite. Finally, a video call with the CEO. I was rejected 2 days after the final call. Over the course of these interviews, they asked all the major types of questions - behavioral, past experience, java and sql fundamentals, leetcode (more modern "realistic code base"-style), algorithms, and some systems design. Quite a bit of casual conversation involved as well. I thought their interview process was great. By asking such a diverse set of questions, they gave me opportunity to showcase many potential strengths. They left no stone unturned. The process ran pretty long, but the interviewers were enjoyable company so it didn't feel like a waste of time.