I applied online. The process took 2 weeks. I interviewed at Jane Street in Apr 2011
Interview
The process consisted of 3 phone interviews (I suspect that there is a last one in their office).
The first interview was about general math and concepts of computer science/functional programming. I had a few brain teasers (7^3, number of edges in a cube, a classic dice roll exercise).
The second interview was centered around designing algorithms, so mainly computer science related. The idea was to shuffle, sort and use arrays.
The last interview was mostly puzzles, including a rather complicated dice roll exercise and a puzzle.
Interview questions [1]
Question 1
You have 2 identical plates which break when thrown higher than a specific number of stories. You are in a 100 story building. What is the least number of tries you must do to determine the story number after which the plates are broken when thrown off the building?
I applied online. The process took 1+ week. I interviewed at Jane Street (New York, NY) in Dec 2017
Interview
Applied online through the website. Received a request for a phone interview the same day. Phone interview was about 40 minutes and consisted of one programming question conducted over coderpad.io. Interviewer was pleasant and helpful. Received a rejection back a week later.
Interview questions [1]
Question 1
Implement data structures and evaluation function for a stack machine given certain instructions that operate on a stack of data (ints and strings).
I applied online. The process took 4 weeks. I interviewed at Jane Street (Chennai) in Aug 2017
Interview
Had a phone interview with one of their devs. 45 mins long. Had three questions. They gave me an API and I had to use it to solve some basic questions. Would be a good question to revise Hashing, Data Structures. Wasn't too specific on complexity.
Interview questions [2]
Question 1
Given an spreadsheet API with functions -> GetValue(), SetValue(), SetFormula(), how will you calculate the sum of an array?
I applied online. The process took 2 months. I interviewed at Jane Street (Hong Kong) in May 2017
Interview
I applied online and received an email a few weeks later from a recruiter for a technical phone interview, which lasted for an hour.
I got a response within days, they invited me to an onsite interview where they did two interviews ~45 each, coding on a provided laptop. I stumbled for a bit trying to find an efficient solution. The interviewers were friendly, guiding me with possible improvements and pointing out edge cases. I got the email a week later saying they would be looking for other candidates.
Interview questions [1]
Question 1
Given two strings representing big numbers, and an operator (+/-), calculate and the return the result of that operation as a string.