Software Engineer

QNT Partners; United States; Remote; USD 180,000 - 300,000; Full time

Benefits offered by this job

Competitive compensation

Performance upside

Job summary

QNT Partners seeks an elite C++ engineer to join its fast-moving HFT group in the United States. You’ll write and tune the core trading stack, pushing for speed, safety and determinism while owning impactful code paths.

Work with top traders and researchers to optimize latency, memory layout, and CPU caches. Expect a flat, ownership-driven team where your work directly influences PnL and production-grade tooling and deployment.

Qualifications

• Minimum 2+ years building high-frequency/low-latency trading systems.
• Expertise in modern C++ (C++20+) and thoughtful use of features.
• Fluency with Linux, network stack, and system calls.
• Strong understanding of memory layouts, caches, and lock-free tech.
• Experience with performance profiling to validate improvements.
• Experience collaborating with traders/researchers to productionize ideas.

Responsibilities

• Build and optimise ultra-low-latency C++ for core trading and market connectivity systems.
• Hunt down jitter, cache misses and branch mispredictions, and measure everything twice.
• Work closely with traders and researchers to turn their ideas into production code, fast.
• Help shape tooling, testing and deployment so it can ship safely and often.
• Review code, share knowledge and make the team sharper.

Skills

High-frequency trading experience

C++20+

Linux proficiency

Performance profiling

Memory/CPU architecture

Networking & OS fundamentals

Job description

(Must Have; Prior HFT experience and Right to Work in EMEA, No Sponsorship)

The firm:

A small, fast-moving trading firm operating in a very competitive corner of the market. Its systems make a very large number of decisions a day, and it would like them made a little quicker than everyone else's. The team is compact, with no layers of management and no committee to approve a pull request. Every engineer gets real ownership by seeing how their code positively impacts PnL.

The role:

You’ll sit in elite team of engineers from the best HFTs in the world to write and tune the C++ at the heart of the firm's trading stack and spend your days making things faster, safer and more deterministic. You'll also spend them explaining to colleagues why a "harmless" heap allocation on the hot path is, in fact, a crime.

Responsibilities:

• Build and optimise ultra-low-latency C++ for the core trading and market connectivity systems.
• Hunt down jitter, cache misses and branch mispredictions, and measure everything twice.
• Work closely with traders and researchers to turn their ideas into production code, fast.
• Help shape the firm's tooling, testing and deployment so it can ship safely and often.
• Review code, share knowledge and make the team sharper.

You’ll have:

• Strong modern C++ (20 and beyond), and real opinions about when not to use its fancier features.
• Solid tenure in previous roles or good reasons for shorter stints (client's orders not ours).
• At least 2 years of experience building high-frequency / low latency trading systems in a top-tier trading firm.
• An understanding of what happens below the abstractions: memory layout, CPU caches, lock-free techniques, networking and the OS.
• Performance profiling and benchmarking experience, and the patience to prove an optimisation worked.
• Fluency in Linux and comfortable around the network stack and system calls.

Nice to have:

• Previous experience in HFT, market making or another latency-critical environment.
• Exposure to kernel bypass or custom networking.
• Python for tooling and analysis.
• A "my most cursed template metaprogramming bug" story you're willing to share.
• Hard problems where speed is the product, and where an engineer's work shows up in the results quickly.
• A flat, low-ego team where good ideas win, whoever has them.
• Flexible working, with the option of an office for those who prefer it.
• Competitive compensation with performance upside.
• Colleagues who care about craft and don't mind the occasional bad pun.