I applied via Jobteaser, I was contacted shortly after my application. Then I had a video-interview with the manager of the team, who asked me about my previous experiences then gave me some brainteasers. Afterwards I participated in a recruitment day with other candidates: It started with a general presentation of the company, then an individual interview with one of the co-founders, it was more like a discussion about my passions (we talked about geopolitics and international politics, then about my travels). Then he gave me a brainteaser. The second interview was with two HRs who asked me personality questions and gave me a brain teaser. The last interview didn't take place but instead the first interviewer told me that there they decided not to move further as they want someone more independent and who thinks out of the box.