3 part interview: 1) 30 min phone call with University Recruiter (easy, friendly, talked about my experience, etc.) 2) Take home challenge. Given a data set, code up analysis, include code in response and write 1-2 page report with findings/learnings. They said it should take 5-6 hrs, I spent ~2x that. This was stressful, they only gave 48hrs to do it, but it was also really fun. 3) Virtual interviews with a recruiter and 3 Duolingo employees. A (very easy) SQL task, chat/problem solving with a Data Scientist, and an interview about how I work on a team. All told, ~2.5 hrs. They got back to me quickly at all stages (including rejection). Everybody was really nice. Not sure what ruled me out, but I was definitely disappointed not to get to work there. Hope that someone great got the job!