The major part of the interview was hosted by two very nice people, one was hiring manager, another one was high-level manager. Both of them were extremely pleasant to talk to. The interview was quite informal and felt more like friendly chat between co-workers rather than actual interview. It immediately felt like being in the family.
After the main part, I also had a short interview with the director of the organisation. And then I had a chat with one of the modellers, who gave me an assignment, which was a part of the selection process. And with him again, we immediately got into nice friendly chat.
Overall, it was the nicest (!) interview, I have ever been to. And people working there are really nice and welcoming. It feels immediately. The team is really small and they value their team spirit and some of the discussions on the interview were specifically directed into finding out whether the candidate will fit the team.