A short SQL exam followed by a 3 stage interview of phone, group in person and a one to one with the CTO. I found the fact the CTO took an hour to meet with me to gauge if I was a right fit for the company and team very positive as it showed that they are looking to build a long term culture within the company. The key focus of the interview seemed to be testing logical reasoning and communication skills. My answers weren't always perfect but I explained how I got to them and why, which was more important than being correct at times. Slightly longer than most, but understandable considering the nature of the work.