I applied online. The process took 3 weeks. I interviewed at Jane Street
Interview
Applied and was asked for an interview the next day (delayed interview, however, because I was too early for the intern interview process). Had an interview a few weeks later. It was difficult. I was asked to write a memoized form of a function, evaluate its time complexity, then memory. Then I was asked to improve its memory cost. The answer, I believe, was to implement some sort of LRU stack (which I said some form of), however the interviewer seemed to zone out about 15 minutes until the end of the interview. I must have been too slow to answer or something, because he zoned out and I heard typing on his end towards the end, so even if I got it in the end it was already a no.
It was a very quick and painless process. Recruiter very responsive, kind interviewers. High implementation and difficult problems, so failed onsite after 3 interviews and a Question and Answer Session.
Did not pass the initial coding round. I tried to explain my thought in details to the interviewer but failed to translate my thought into code. So far interviewer is very nice.
I applied online. I interviewed at Jane Street (New York, NY)
Interview
My experience interviewing at Jane Street was definitely challenging, but also surprisingly collaborative. Instead of focusing only on whether I could get the right answer quickly, the interviewers were much more interested in how I approached problems and explained my thinking. I worked through a few coding questions involving data structures and algorithms, and there were also some probability-style questions that tested logical reasoning. The interviewers were clearly very sharp, but they were also approachable and encouraged me to talk through my thought process the entire time. When I got stuck, they would sometimes guide me with small hints so we could keep exploring the problem together. Overall, it felt less like a typical high-pressure interview and more like a thoughtful technical conversation with experienced engineers.
Interview questions [1]
Question 1
“What is the expected number of coin flips needed to get two heads in a row?”
