They were friendly. I was interviewing with a group of 3 engineers. We went over my resume, they asked questions and gave me feedback on my resume writing :) We talked about their projects and walked through the details. Then they asked me to write a piece of C code on board. It wasn't difficult at all. Then they left the room and talked to the CTO. Overall, it seems we could not find the chance of working together (due to logistical issues) but the process was absolutely positive. I wish them good luck.