Hudson River Trading hires Algorithm Developer (quant research and trading), Algorithm Engineer and Software Engineer / Core Developer. Candidates report 3 to 4 interview stages depending on the track (4 distinct rounds across all tracks). Below: what each round tests and how to prepare, the path by track, the timeline, pay and a 4-week prep plan, drawn from candidate reports.
Hudson River Trading interview: quick answer
- StagesBy track: Algorithm Developer (quant research and trading): 4 · Software Engineer / Core Developer and Algorithm Engineer: 3 (4 distinct rounds across all tracks)
- Online assessment~70-150 min - HackerRank / CodeSignal
- TimelineOutside guides report application review of up to two weeks, about three weeks of screens, and four to eight weeks end to end.
- Final roundOnsite: Full day - back-to-back rounds
- Pay (candidate-reported)Algorithm Engineer / Algo Developer, New grad (BS/MS): $750k – $900k total comp
- RolesAlgorithm Developer (quant research and trading), Algorithm Engineer, Software Engineer / Core Developer
Preparing for Hudson River Trading? Work the rounds in order in the free Hudson River Trading interview funnel.
The HRT interview process at a glance
| # | Round | Format and length | Who takes it | Prep |
|---|---|---|---|---|
| 1 | Online Assessment | ~70-150 min - HackerRank / CodeSignal | All tracks | OA guidePractice |
| 2 | Probability & Brainteaser Phone Screen | 45 min - video | Algorithm Developer (quant research and trading) | GuidePractice |
| 3 | Programming Phone Screen | 45-60 min - CoderPad - C++ or Python | All tracks | GuidePractice |
| 4 | Onsite | Full day - back-to-back rounds | All tracks | GuidePractice |
Stages are listed in the order candidates report them. Formats come from candidate reports and change between cycles, offices and teams; the "Who takes it" column shows which track each round belongs to.
How the HRT process differs by track
HRT runs separate loops for different roles. Here is the path each track reports, in order:
- Algorithm Developer (quant research and trading) (4 stages): Online Assessment → Probability & Brainteaser Phone Screen → Programming Phone Screen → Onsite
Candidates report both a statistics screen and a coding screen. One outside guide describes the intern final as four one-hour rounds: extending existing C++ trading code, a data analysis in a notebook, a design discussion and maths. - Software Engineer / Core Developer and Algorithm Engineer (3 stages): Online Assessment → Programming Phone Screen → Onsite
Engineering loops focus on coding, debugging, design and team fit; an HRT engineering blog post quoted by an outside guide says it avoids puzzle-style questions.
Not sure which track fits you? See quant trader vs quant researcher.
Every HRT round: what it tests and how to prepare
1Online Assessment
The biggest cut in the process. Algorithm Developer candidates report a long coding assessment (about 150 minutes, three problems mixing simulation, trees and number puzzles). Software engineering interns report a CodeSignal set of about four LeetCode-style problems in 70 to 90 minutes, and a Quant Analyst variant is a short C++-only test. Graders look at correctness and clean, edge-case-safe code, not just passing visible tests.
Question types: mostly coding, especially sorting and searching, complexity analysis, dynamic programming and divide and conquer. Latest candidate report for this round: Jun 2026.
How to prepare
- Budget ~45 min/problem; bank partial credit and move on rather than sinking 90 min into one.
- Write clean, well-factored code with explicit edge-case handling - HRT reads engineering quality, not just a green test bar.
- Early intern OAs were C++-only; recent sets are language-flexible (Python/C++), but Quant Analyst is still C++.
Hudson River Trading online assessment guide →Practice this round (8 questions) →
2Probability & Brainteaser Phone Screen
A conversational screen on probability and expected value: brainteasers and quick arithmetic, derived out loud with a researcher.
For Algorithm Developer candidates this is a statistics screen (estimator bias, order statistics, expected value), often followed by checking the answer with a short simulation in code. Software engineering candidates usually skip it and take the programming screen instead.
Question types: mostly expectation, probability and statistics, especially expected value, symmetry, conditional probability and discrete probability. Latest candidate report for this round: Aug 2026.
How to prepare
- Drill the classics until reflexive: Gambler's Ruin, coupon collector, expected waiting times, and conditional-expectation setups.
- Derive out loud and state assumptions; HRT cares how you reason to the answer, not just that you have it.
- Be ready to extend a teaser (the n -> N generalisation) and to sanity-check your result with a limiting case.
Full Probability & Brainteaser Phone Screen guide →Practice this round (56 questions) →
3Programming Phone Screen
A live coding round tuned to the team you are interviewing for. For core/low-latency roles expect C++ specifics - pointers and references, memory management, move semantics - alongside an algorithmic problem. Get to a correct first solution, then expect an optimization / complexity conversation.
Question types: mostly coding, combinatorics and stochastic processes, especially data structures, sorting and searching, complexity analysis and greedy. Latest candidate report for this round: Jun 2026.
How to prepare
- For C++ roles, be fluent in pointers vs references, ownership, and move semantics.
- State complexity as you go and propose the optimization before being asked.
- Test your code on edge cases out loud - clean handling is part of the grade.
Full Programming Phone Screen guide →Practice this round (24 questions) →
4Onsite
A full day of back-to-back sessions (virtual or in person). Multiple programming rounds (harder than the screen, with optimization and systems-level reasoning), a systems / architecture discussion, problem-solving, and a project / behavioural deep-dive that probes collaboration, teachability, and communication. HRT weights how you think and work with others, not just whether you reach the answer.
- Onsites include a data-analysis round in a notebook; fluency with pandas and plotting helps, and documentation is allowed.
- A common pattern: derive a strategy for a game, then check it with a quick simulation.
Question types: mostly statistics, coding and market microstructure, especially hypothesis testing, time series, expected value and poisson process. Latest candidate report for this round: Jun 2026.
How to prepare
- Treat every round as a collaboration - narrate, take hints, and iterate.
- Expect a harder second coding round than the screen; have an optimization mindset.
- Be ready to defend design choices and discuss systems trade-offs at depth.
Practice the HRT rounds in order
Each round in the HRT funnel has its own practice set, with worked solutions and progress tracking. A free account saves your progress across rounds.
Timeline
- Application review takes up to about two weeks, per HRT guidance quoted by an outside guide.
- The phone screens take about three weeks; one guide puts the full process at four to eight weeks.
- The online assessment is not always automatic: candidates report a CV screen first, and some report rejections after strong scores.
Application rules
Outside guides quoting HRT's careers FAQ report that you should apply to one posting (you are considered for other suitable roles), that AI tools are not allowed during interviews, and that Algorithm Developer candidates may choose C++ or Python for coding.
Intern vs full-time
For 2027, outside guides tracking HRT's postings report a separate Algorithm Developer posting for PhD students, a new Data Scientist internship, and a software engineering internship open to undergraduates only. The intern Algorithm Developer final is reported as four one-hour rounds; the full-time final has fewer public reports.
Recent changes
- 2027 intern cycle: new Data Scientist internship and a separate PhD Algorithm Developer posting (outside guides tracking HRT postings).
- August 2026: QuantVault candidates report a change in the Algorithm Developer online assessment problem set.
A 4-week HRT prep plan
Built from the order of Hudson River Trading's rounds on the Algorithm Developer (quant research and trading) path and the topics in each round's practice set. Compress it if your first interview is sooner. Other tracks can swap in their own rounds from the table above.
| When | Focus | What to do |
|---|---|---|
| Week 1 | Foundations | Review coding, expectation and probability, the topics that dominate Hudson River Trading's practice sets. Start with Quant coding course and Probability course. Work the easy and medium questions in the Hudson River Trading question set. |
| Week 2 | Early rounds: Online Assessment, Probability & Brainteaser Phone Screen and Programming Phone Screen | Practice coding, expectation and probability under time pressure, and read the OA guide. Add a daily mental-math drill. Talk every answer through out loud; interviewers score the reasoning. |
| Week 3 | Later rounds: Onsite | Move to statistics, regression and market microstructure. Do timed coding sessions in your interview language. Read how quant superdays work. |
| Week 4 | Rehearse the full loop | Run each practice round in order, redo the questions you missed, and prepare two project stories plus a specific answer to "why Hudson River Trading?" (see behavioral questions at trading firms). |
HRT pay
| Role | Level | Total comp | Notes |
|---|---|---|---|
| Algorithm Engineer / Algo Developer | New grad (BS/MS) | $750k – $900k | Top of the HFT new-grad market as of 2025. The dominant new-grad track at HRT — most engineering hires land here. The bar (and the price) climbed materially in 2024-2025. |
| Core Developer | New grad (BS/MS) | $500k – $650k | Sits slightly below Algo Engineering for new grads, but still well above industry SWE comp. |
| Algorithm Engineer / Core Dev | Mid (3–5 yrs) | $800k – $1.4M | Performance-tied — top performers in strong years can blow past the upper band. Compensation tightly tracks per-employee P&L. |
| Senior Researcher (AI/ML, PhD) | First year (post-PhD) | $700k – $1.0M | Smaller track, higher bar — heavy PhD weighting. The AI/ML buildout post-2020 expanded this team materially. |
Total compensation means base salary plus bonus and any sign-on, as candidates self-report it. Job postings usually show base salary only, so posted figures and outside salary pages often look lower. These are rough ranges, NOT offers or guarantees. HRT has paid very aggressively in some years; numbers also vary by team and performance. Source: Candidate self-reports aggregated from levels.fyi, Glassdoor, and community Discord — not employer-verified. Last updated May 22, 2026.
Full breakdown by level: Hudson River Trading salary guide.
HRT teams and what their interviews test
Core Developers own the shared trading platform. Senior research roles exist but are smaller. Teams sit close to live trading, not as a sequential research-to-execution pipeline. The firm publicly emphasizes mobility between teams.
| Teams | What it does | What its interviews test |
|---|---|---|
| Algorithm Development Algorithm Developer | HRT's quantitative research and trading role: research, build and run trading strategies. Python + C++. | A statistics and probability screen (often followed by checking the answer with a quick simulation), a coding screen, and an onsite that includes data analysis in a notebook. |
| Algorithm Engineering Algorithm Engineer | Engineers who build and optimize the research and trading systems that algo developers rely on. Python + C++. | Coding round is heavy. Cache-aware thinking, tight complexity reasoning, clean C++/Python. |
| Core Development Core Developer | Shared trading-platform code: data, simulation, deployment, monitoring. Supports every algo team. The second major new-grad hiring track. | Systems-design + concurrency + complexity. Slightly broader than Algo Engineering, less direct on a single strategy. |
| AI / ML Research Senior Researcher | Newer team (scaled up post-2020). Modern ML applied to short-horizon prediction + research workflow automation. Smaller headcount, more senior bar. | Heavy on ML fundamentals + statistical depth. Usually requires PhD or strong industry track record. Not a typical new-grad path. |
| Systems & Networking Systems Engineer | Low-latency networking, exchange connectivity, kernel-bypass, Linux internals. Specialized but well-defined. | Networking + OS fundamentals. Less common interview path for new grads. |
| Hardware Hardware Engineer | Custom hardware, FPGAs, signal-path optimizations. The most specialized HRT track. | Specialist hires — typically requires hardware/FPGA background. Not a typical new-grad path. |
| Trade Operations Trade Ops Analyst | Live execution oversight, risk monitoring, intra-day strategy adjustments. | Conversational round — microstructure intuition, P&L reasoning, behavior under stress. |
About HRT
| Firm type | Single-firm prop trading (no outside capital) |
|---|---|
| Trading style | Systematic; strong AI/ML emphasis in recent years · High-frequency + mid-frequency |
| Founded | 2002 |
| Headquarters | New York, NY |
| Other offices | London, Singapore, Boulder, Chicago |
| Net trading rev. | ~$8B (2024) |
| Employees | ~1,400 |
| Reported performance | ~$8B NTR (2024, record) |
| Online assessment | 2 to 4 medium to hard coding problems, roughly 70 to 150 minutes |
Founded 2002
Founded in 2002 by Jason Carroll, Alex Morcos, and Suhas Daftuar. HRT scaled by being one of the earliest HFT firms to treat low-latency engineering as a first-class problem on par with alpha research.
Tech stack
C++ is the production language for trading paths. Python dominates research and tooling. Heavy on Linux internals and custom networking. Many engineers have systems-programming or compiler backgrounds. If your CV mentions C++, expect a deep follow-up; if you only know Python, that's still fine for the research-leaning tracks.
P&L and positioning
HRT trades its own capital — no outside money. Reportedly responsible for a meaningful share of US equity volume on busy days, and public coverage points to per-employee P&L among the highest in the industry — multi-billion gross trading P&L in strong years. That economic profile is why HRT comp is at the top of the HFT band. Materially expanded ML/AI investment since ~2020; recent algo strategies lean increasingly on modern ML rather than pure low-latency arbitrage.
Culture and leadership
Co-founder Jason Carroll remains active in technical direction; co-founders Morcos and Daftuar departed in 2012.
Culture
Engineering-driven, low-ego, code-quality-obsessed; the firm reads more like an elite tech company than a Wall Street trading desk. Heavy investment in ML/AI infrastructure since ~2020.
What the interviews feel like
Heavy on coding (C++/Python) and mental-math probability. Fast-paced. Multiple rounds back-to-back, often a coding round AND a mental-math round on the same onsite day.
Practice for HRT on QuantVault
Practice
Courses
Games and drills
Further reading
- How quant superdays work
- Behavioral questions at trading firms
- Mental math for trading interviews
- C++ and low-latency interview questions
- Market-making game interview guide
- The quant interview process, explained
Similar firms to compare
Firms with a similar business and interview style. Many candidates interview at several of them in the same cycle.
Sources and how this guide is built
- Updated October 20, 2026; firm data last reviewed May 22, 2026; pay last updated May 22, 2026.
- Round detail draws on 154 questions candidates report from Hudson River Trading interviews (the most recent report across all rounds is from Aug 2026). A separate curated HRT question set of 106 problems collects the most useful practice for this firm.
- Public candidate reports and outside interview guides are cross-checked against each other. Where they disagree the page says "reports differ"; details from a single source are marked as candidate reports.
- No actual interview questions are reproduced on this page. The questions, with worked solutions, are in the practice rounds.
HRT interview FAQ
How many rounds are in the Hudson River Trading interview?
It depends on the track: Algorithm Developer (quant research and trading): 4; Software Engineer / Core Developer and Algorithm Engineer: 3 stages. Across all tracks candidates report 4 distinct rounds: Online Assessment, Probability & Brainteaser Phone Screen, Programming Phone Screen, Onsite.
How long does the Hudson River Trading interview process take?
Outside guides report application review of up to two weeks, about three weeks of screens, and four to eight weeks end to end.
Is there an online assessment at Hudson River Trading?
Candidates report one: ~70-150 min - HackerRank / CodeSignal. Graded on correctness AND clean, tight, edge-case-correct code, not just visible tests.
What happens in the Hudson River Trading final round?
Onsite (Full day - back-to-back rounds). A full day of back-to-back sessions (virtual or in person). Multiple programming rounds (harder than the screen, with optimization and systems-level reasoning), a systems / architecture discussion, problem-solving, and a project / behavioural deep-dive that probes collaboration, teachability, and communication.
Does the Hudson River Trading process differ by role?
Yes. Algorithm Developer (quant research and trading): Online Assessment, Probability & Brainteaser Phone Screen, Programming Phone Screen, Onsite. Software Engineer / Core Developer and Algorithm Engineer: Online Assessment, Programming Phone Screen, Onsite.
How much does Hudson River Trading pay?
Candidate-reported total compensation: Algorithm Engineer / Algo Developer (New grad (BS/MS)) $750k – $900k; Core Developer (New grad (BS/MS)) $500k – $650k; Algorithm Engineer / Core Dev (Mid (3–5 yrs)) $800k – $1.4M; Senior Researcher (AI/ML, PhD) (First year (post-PhD)) $700k – $1.0M. These are self-reported totals including bonus, not offers; job postings usually list base salary only.
How should I prepare for the Hudson River Trading interview?
Prepare round by round over about four weeks: foundations first, then the early rounds (Online Assessment, Probability & Brainteaser Phone Screen, Programming Phone Screen), then the later rounds, then a full rehearsal. Each round has its own practice set on QuantVault, and the online assessment has a dedicated guide.
What does Hudson River Trading do?
Hudson River Trading is a single-firm prop trading firm headquartered in New York, NY. Founded in 2002 by Jason Carroll, Alex Morcos, and Suhas Daftuar. HRT scaled by being one of the earliest HFT firms to treat low-latency engineering as a first-class problem on par with alpha research.
Is Algorithm Developer a quant or an engineering role at HRT?
Algorithm Developer is HRT's quantitative research and trading role; Algorithm Engineers build the systems that support it. Algo Dev candidates get both a statistics screen and a coding screen.
Can I apply to more than one HRT role?
Outside guides quoting HRT's FAQ say to apply to one posting; you are considered for other suitable roles.
Can I use AI tools in HRT interviews?
No. Outside guides quoting HRT's FAQ say AI tools are prohibited during the interview process.
Should I use C++ or Python at HRT?
Algorithm Developer candidates report a free choice between C++ and Python. Core and low-latency roles expect C++ specifics such as memory management and move semantics.
Start preparing for Hudson River Trading
Open the interactive Hudson River Trading interview funnel: every stage with its practice set, from the first screen to the final round. Create a free account to save your progress.