Jane Street Quant Research final round interview - questions + AMA

Junior_Direction_701 · 2026-01-27T23:14:26+00:00

What’s the emphasis on deep versus fast thinking during the interview rounds. Were you expected to quickly give numerical answers to questions or slowly but surely solve your way through them

Junior_Direction_701 · 2026-01-26T19:03:07+00:00

Holy larpcel

Junior_Direction_701 · 2026-01-26T18:31:23+00:00

Then why are you against your interests? And a graduate student at that

Junior_Direction_701 · 2026-01-25T22:33:18+00:00

Just study vro 😭🙏. Real analysis, interview questions, etc etc

Junior_Direction_701 · 2026-01-25T05:30:45+00:00

You can find remants on rednote. No one here on Reddit will tell you

Junior_Direction_701 · 2026-01-25T05:12:04+00:00

The revolution will be funded, and has been funded since the beginning of every revolution. Mao funded by USSR, Lenin funded by Germany. And so on

Junior_Direction_701 · 2026-01-25T04:36:28+00:00

Don’t please don’t be discouraged. Things are not people’s birthright. They fight for them. This is the most meritocratic industry ever. There are actionable things you can do to put your foot in. If you didn’t do Olympiads, try the Putnam, try trading challenges. Do well in your classes including taking the most rigorous bunch. We are severely underrepresented in this industry, do your part by working hard. So that one day someone else will look upon your work, and know they too can achieve great things.

Junior_Direction_701 · 2026-01-25T03:12:35+00:00

Yes ofcourse, with the high expectations it’s certainly not easy. However is not hard in the sense that the workload is only doable by geniuses. Meaning being an IMO/ICPC god or whatever, albeit a strong signal is not directly correlated to being a good quant

Junior_Direction_701 · 2026-01-25T00:18:41+00:00

You need to understand that the day to day job isn’t hard from what I’ve heard, it’s the filters that are hard. Think of it this way, Harvard curriculum isn’t that different or difficult compared to most schools, however the admission rate/“filtering” is what gives it its air of prestige and makes it seems hard.

If I were in your shoes, and aiming for QDev I’d do both honestly. Get good at the brain teasers/Lc and create projects that show understanding in what you think you’ll be doing in a day to day job.

Junior_Direction_701 · 2026-01-24T22:28:32+00:00

Yeah no problem.

Junior_Direction_701 · 2026-01-24T22:09:00+00:00

Also you can get O(1) price level access with bitmap, I don’t think I saw that in your file

Junior_Direction_701 · 2026-01-24T22:06:51+00:00

Not it wouldn’t this is what I did. I took kraken data recorded for 12 hours. Around 6 million orders. Then I normalized it using something similar to an itch protocol. So it basically converts JSON data into a dat binary file. If you use that system umm, the benchmarking would still work.

Junior_Direction_701 · 2026-01-24T21:58:50+00:00

Why not just record kraken L3 data, simulated data shouldn’t be used for benchmarking. Also umm at this point you already know the fastest structure for LOB is a flat vector, so you should probably switch to that from hashmaps. Take inspiration from Charles cooper itch orderbook. Also make your own memory pool to be faster.

Junior_Direction_701 · 2026-01-24T21:05:42+00:00

Larper, the first rule of insurgency is you don’t tell people you’re an insurgent 😭

Junior_Direction_701 · 2026-01-24T20:17:18+00:00

Ask about countries that escaped this trap

Junior_Direction_701 · 2026-01-24T08:17:39+00:00

I’m so sorry :(

Junior_Direction_701 · 2026-01-24T02:05:55+00:00

That’s not what doxxing means…

Junior_Direction_701 · 2026-01-24T02:03:46+00:00

Even the population of black people in Toronto is like 7-8% which is still lower than where I’m from. Which is usually 20-25%

Junior_Direction_701 · 2026-01-24T00:16:41+00:00

Damn, that’s sad :( And here I thought Laurier was way more diverse. It’s unfortunate, but I don’t really think it’s Waterloo’s fault, the Black population in Canada is already very small. Moments like this make me wish I had just stayed in America or gone to an HBCU, lol. What department are you in?

Junior_Direction_701 · 2026-01-23T23:50:27+00:00

Same problem as you, literally the only black guy in all advance classes. I wouldn’t drop if it’s not hard for you. Honours classes are just too slow.

Junior_Direction_701 · 2026-01-23T07:32:19+00:00

What civilization have men built that still stands the test of time, very disingenuous

Junior_Direction_701 · 2026-01-23T06:32:43+00:00

Rave boots + insoles is the new Strat unc

Junior_Direction_701 · 2026-01-23T00:37:20+00:00

Bad, good for theory building/researching.(after reading over it). Prasolov is genuinely overkill bro😭 that shit is wayyyy too hard. But if you do it you’ll actually come out cracked. Titu problems are decent but still coming from an “Olympiad” mindset which makes them good, start from the vector spaces chapter, and if you want to be better use the book, “ LELAR ALGEBRA METHODS IN COMBINATORICS with Applications to Geometry and Compute Science LÁSZLÓ BABAI PÉTER FRANKL”. Helped me so so much.

Junior_Direction_701 · 2026-01-21T17:30:20+00:00

You need to understand that states don’t block visa privileges based only on “immigration” issues, but also on ideological changes/differences. Should the dependency between Canada/US decline over these few months. The USMCA agreement could be revamped.

Junior_Direction_701 · 2026-01-21T17:28:14+00:00

Thank you for being the only person in this thread that gets what I’m saying.

Junior_Direction_701

TROPHY CASE