PRACTICE GUIDE BELVEDERE TRADING
Belvedere Trading Coding Challenge: what the test is, and how to train for it
The Belvedere Trading coding challenge screen is 2 questions in 30 minutes - about 15 minutes each - written in a code editor and run against tests you cannot see. There is no negative marking, so leaving an item blank gains you nothing over guessing.
Where it sits: Coding challenge. The practice sitting on this page runs the same item count, the same clock and the same marking rule, with questions generated by Outcry rather than taken from Belvedere Trading.
Outcry is not affiliated with Belvedere Trading and has no access to their assessment content. This guide describes an assessment format that candidates report publicly; the questions here are generated by Outcry and are not Belvedere Trading’s own.
What it screens
A Chicago-based proprietary trading firm specialising in options market making and derivatives strategies.
- ✓Reading concurrent code and pointing at the defective line
- ✓Order-book data structures: what happens on a cross, a cancel, a partial fill
- ✓Algorithmic complexity chosen for the input sizes stated in the problem
- ✓Monte Carlo methods and when a simulation beats a closed form
Where it sits at Belvedere Trading
This section does not arrive on its own. It closes the paper, and the sitting around it runs 55 minutes and 16 items in total, with Probability and logic on the same continuous clock. Candidates who prepare only for this round tend to be caught by the pacing of the rest.
There is no going back. You answer or skip, and the next item loads, which means the decision to leave an item is final at the moment you make it.
The format
These are the numbers the Belvedere Trading sitting on this site runs on, matching the format candidates report.
| Questions | 2 |
|---|---|
| Time | 30 minutes |
| Per question | 15 minutes |
| Negative marking | No |
| Answer style | Code editor, run against hidden tests |
| Where it sits | Coding challenge |
What it tests, with a worked example
Every example below is generated by Outcry, drawn from the same question generators the timed drills run. None of them is Belvedere Trading’s.
Data structure implementation
Build the thing rather than call it: an order book, a cache, a ring buffer. Graded by hidden tests, so there is no partial credit for an approach.
Complexity that is actually graded
Hidden tests sized so the naive solution times out. A correct answer that is too slow scores the same as a wrong one.
Reading someone else's code
A diff or a function with a bug in it, and the question is where.
Example
Which change most reduces cache misses when summing a large matrix?
- Use a larger integer type
- Iterate in row-major order matching the memory layout
- Unroll the loop 2×
- Mark the accumulator volatile
Answer Iterate in row-major order matching the memory layout
Sequential access uses the whole cache line that was fetched. Striding across rows discards most of every line.
Language and systems detail
Memory, references, undefined behaviour and the things that bite in production.
Example
A block code has a minimum Hamming distance of 8. How many bit errors can it correct?
- 8
- 3
- 4
- 7
Answer 3
Correction needs 2t + 1 <= 8, so t = floor((8 - 1)/2) = 3. The same code can detect 7 errors, which is the number this question is usually confused with.
Edge cases
Empty input, one element, duplicates and overflow. The hidden tests always include them.
Probability behind the problem
Screens that look like coding questions and are really expectation questions.
Example
Daily P&L is normal with mean 180 and standard deviation 6. What share of days come in above 192?
- 2.3%
- 97.7%
- 1.1%
- 4.6%
Answer 2.3%
192 sits exactly 2 standard deviations above the mean. The 68-95-99.7 rule leaves about 5% outside that band and half of it in the upper tail, so 2.3%. Forgetting to halve is the usual slip.
What a good score looks like
On a paper of 2 questions with no penalty for a wrong answer, the only thing an unanswered question can do is cost you. Coding screens are usually pass-fail on hidden tests rather than scored, and candidates commonly report that a solution passing every correctness test still fails on a timeout. Treat full marks as solving every problem inside the complexity bound, not merely solving it.
How to train for it
- 01Implement the core structures from scratch once each. The screens ask you to build them, not use them.
- 02Write the edge cases into your own tests first. That is where the hidden ones live.
- 03Practise without an autocomplete. The screens run in a bare editor, and the gap between writing code with help and without it is larger than most people expect.
TRAIN IT HERE
The drills that match each section
Concurrency Clash
Find the data race, name the fix - real C++ defect patterns, five levels.
Order Book
Matching-engine mechanics: crosses, cancels and partial fills.
Algorithm Lab
DP tables, Monte Carlo estimation and speed rounds at four difficulty tiers.
SIT THE FULL BATTERY
All the sections back to back on one clock, marked the way the real screen marks them, with a by-skill breakdown at the end. Included with any pass.
Also reported at Belvedere Trading
Common questions
- Is the Belvedere Trading coding challenge test multiple choice?
- Code editor, run against hidden tests. You write and run code against tests you cannot see.
- How long is the Belvedere Trading coding challenge test?
- 2 questions in 30 minutes, which is about 15 minutes each.
- Is there negative marking on the Belvedere Trading coding challenge test?
- No. A wrong answer costs nothing beyond the mark you would have earned, so leaving an item blank is never better than guessing at it.
- How do I practise for it free?
- Every drill linked on this page is free to play, with no account, inside a daily run cap. Questions are generated fresh each run, so there is nothing to memorise between attempts. The full Belvedere Technical Challenge sitting puts the sections back to back on one clock.