Relatively typical interview process. I had a phone call with a recruiter where I talked about my background and understood the available roles: Full Stack Engineer and Back End Engineer.
Next, there was a project depending on which role you were applying for. I did the back end project because it suited my experience better.
Following that, I had a video interview with an engineer. I expected this to be a technical review of my project (based on my own past experiences) but it was a traditional engineering/algorithms style interview. Some easy stuff, some medium stuff, but overall approachable. The interviewer was under the impression that I was interviewing for the full-stack position
After the video interview, I had an onsite. This was a full day of 1-1 interviews with the team. The people were: 2 backend engineers who asked various logic/coding problems, CTO who asked about general backend software engineering, full-stack engineer who asked asked about solving a problem that affected every part of the stack, front end engineer who asekd about vanilla JS/css stuff, and finally a meeting with the recruiter to get takeaways for the day.
During one of the interviews, i was informed that knowing react/redux was a prerequisite for the role. In my interview with the recruiter at the end, I asked a few more targeted questions about what they were looking for and communicated clearly that I did not know front end technologies proficiently but that I'd be happy to learn. At no point did anyone ask about the project I did for them, which I found a bit discouraging because I spent a good amount of time on it.
Overall they seem like a great company with many talented people, but I just wasn't a good fit for the roles they had open at the time. This would have been nice to find out earlier given the amount of effort/travel, but mistakes happen.