I had four rounds of interviews, with a lunch break with the manager in the middle.

The first round focused on system design and a relational database. The middle two were standard coding and problem-solving rounds. The last one also included a coding question. We also discussed the problem from the take-home coding assessment, some JavaScript fundamentals, and questions about testing and QA mindset.

I'm posting this review because it was one of the most comfortable interviews I've ever experienced, which is also why I accepted the job.

I felt I could genuinely talk to each interviewer at the end of our sessions. We discussed several aspects of the company, including some benefits that were very appealing. I connected best with the last interviewer, who turned out to be my direct teammate!

I don't remember. I think the easiest was something about the Fibonacci sequence.