I had two rounds of interviews at their office in London. Mainly questions about my CV with a few brainteasers and one coding challenge. The whole process was quite enjoyable although they didn't reimburse my travel expenses. Despite answering all the technical questions correctly I didn't get an offer, due to my lack of "sector-specific experience". Assuming this was the real reason, it could have easily been discerned from my resume without the need of wasting both parties' time and money. General impressions: cool company, good vibe and some of the employees are quite smart; serious doubts about their technical division, with easy questions and a CTO who doesn't understand time complexity being big red flags.