Jane Street Quantitative Trader interview experience

It started with probability and game-style problems, and the whole thing felt like sitting down to solve one clean sequence of questions with someone who would nudge me if I got stuck. I remember one game with red and blue balls that escalated in complexity, and I had to keep explaining the reasoning as it became harder and more constrained.

The next part of the journey had a similar vibe: time pressure, a couple of EV/game questions, and an expectation that I could justify the optimal strategy rather than just compute. When I needed it, hints were available, but there wasn’t much small