The phone interview was very difficult. They mostly asked probability type questions and were interested not only in your solution but your process as well. You definitely need to be well versed in mathematical probabilities to do well. Pretty fair interview overall.
I applied through a recruiter. I interviewed at Jane Street (Hong Kong)
Interview
My first interview was a video call, programming interview. After this round I was invited to the onsite interview rounds and flown to the HK office. Did 2 rounds of programming problems, before being told I was unsuccessful.
I applied online. I interviewed at Jane Street (New York, NY)
Interview
Nontrivial leet code questions, medium to hard range with focus, some mock games, and in-depth follow-up / edge case questions. 1 screening round follow by onsite that was 4-5 interviews.
Interview questions [1]
Question 1
Can disclose exact questions but leetcode medium + with multi-stage questions on how to optimize things further.
It was a great interview process. The interviewer was very nice. The coding question is so so level, but really focus on your communication skills. Got rejected even if I passed all the tests.