Process was very smooth, and HR was on-top of it. I had an initial call with HR, a technical phone screen with a seasoned engineer, and then a two round on-site (each with 2 employees, including the CTO). The only thing that stood out as unconventional to me is that they don't do code reviews. There's definitely pros-and-cons for this, and if it works for them, then it works. The office is lovely and is pleasant to be in.
All the technical questions asked were fair. Get ready to whiteboard and vocalize your thought process. While I didn't end up getting the offer, as I think they went with another candidate, I'd love to interview again in the future, as everyone is friendly and I felt a solid cultural-fit with the firm.