I found the interview process to be highly pleasant and professional.
The first interview was with the group manager. I was asked to describe a system I worked on in the past, and then design a specific system.
The second interview was a coding exercise, nothing particularly challenging if you can write code that works in a timely fashion.
The HR interview was the first one in their offices, which are so nice. The interview itself was very pleasant, I got to hear more about the firm.
After that I asked to speak with the group lead again to hear more details about the project, which sounds very interesting.
I ended up taking a different offer, but I wish I could take this one as well.