I think I applied in Sept 2024 with a mediocre resume from Africa and was totally surprised to receive r1 interview. It emphasized the point that Jane Street doesn't base their hiring plans based on school's prestige.

CV then phone interview of around 30 minutes. The interviewer was nice and helpful. Questions in the first round were about probability, e.g. dice games, basic but with some harder followups.

I did some rounds of zoom meeting. They asking almost only technical questions for trading mainly trading games (no behavioral or HR questions). If you passed round after round then you have a super round for final interview!