After a first introductory video interview on Skype, I was invited to their office for an interview on-site; this consisted in giving a presentation, then an interview with the group leader and main assistant, then a brief chat with the director. Honestly, it felt like they were interviewing me for a different position than the one I had applied to: had I known it before, I would not have applied at all. Some questions did not seem to me particularly professional, and did not even tell me what the next steps were going to be. On a positive note, they refunded my travel expenses very quickly.