Web3 Developer Jobs in United Kingdom, Europe

About Us

OpenFX is on a mission to move money as freely as data, unrestricted by time zones, banking hours, or legacy systems. We are building the infrastructure that will power the next generation of cross-border payment systems for institutions. The team's execution has been exceptional, and we're scaling at a remarkable pace. Our stellar early team comes with experience in companies like J.P . Morgan, Goldman Sachs, FalconX, Paypal, Affirm, Polygon, Kraken, Nium & others. We’re backed by Accel, Lightspeed, NfX, and other top-tier investors.

Role Overview

We're hiring a quantitative trader/developer for Capital Markets which covers trading, hedging, and market-making strategies across our stablecoin and FX business. You'll have the opportunity to work directly with the trading desk on strategies with real, immediate P&L impact, with daily 1:1 mentorship from the experienced traders and engineers leading Capital Markets.You're evaluated on the strategies you ship and the P&L they generate. You own a thread from idea to live trading, and the person you're building it with is a trader.We're specifically looking for someone with a trading background: a prop trading firm, a crypto market maker, or a trading platform where you've both written the code and owned the trading decision it produced.

Key Responsibilities:

• Trading strategy development. Develop, maintain, and improve trading and hedging strategies across our stablecoin and FX business, from idea to live execution, with full ownership of the outcome.
• Production trading systems and live operations. Own the reliability, observability, and operational performance of our live trading environment. Monitor systems in real time, act as primary responder to production issues, and work with the desk to investigate, mitigate, and resolve incidents affecting trading, risk, or system stability.
• Production tooling and operational safety. Build and improve internal tools, dashboards, alerts, and automation that reduce manual intervention in live trading. Design and maintain safe testing, deployment, rollout for production changes.
• Market microstructure and research. Build tools to research how our markets actually trade, and work with the desk to turn that analysis into an edge.
• Full-cycle ownership. Engage in full-cycle trading development — research, coding, testing, and deploying into production.
• High Agency: Bring ideas to the desk unprompted and be ready to defend them. Find the competitive edge that drives results.

What we are looking for

Must-haves:

• Comfortable writing production code and owning a trading decision and its P&L on the same strategy.
• Skills in probabilistic thinking and mathematical reasoning, with the ability to react quickly and accurately to rapidly changing market conditions.
• 3+ years of solving hard problems through code with real metrics and impact in industry, and strong development skills in Python and/or C++.
• Real experience in market making, prop trading, or a trading-adjacent quant role.
• Competitive spirit, a drive to improve, and an appetite for risk-taking.
• Comfortable with abstract, ambiguous problems - explore a venue or a strategy, you don't wait for a spec.
• Self-directed enough to learn a substantial new domain on the job - a new venue, a new asset class, new infrastructure.
• Reliable, predictable availability around scheduled market-moving events.
• Extreme attention to detail

What helps you stand out

• Experience at a prop trading firm, HFT shop, or crypto market maker (Jane Street, Two Sigma, XTX, Jump, Wintermute, Cumberland/DRW, or similar).
• Proven research background in an academic or professional environment, with expertise in statistics or machine learning.
• Experience with on-chain derivatives, DeFi perp venues, or cross-venue arbitrage.
• Experience building or operating stablecoin infrastructure or settlement rails.
• Background in market microstructure, options pricing, or systematic FX trading.

What success looks like

• Your strategies are live and measurably reducing costs or generating P&L on the book.
• You operate independently — your manager is a sounding board on the trade, not someone assigning your work.

What We Offer

• Competitive salary and benefits package.
• Equity in a rapidly growing company.
• Opportunity to work in a fast-paced startup at the forefront of fintech innovation.
• Opportunity to make a significant impact on global financial infrastructure
• Collaborative work culture with emphasis on personal and professional growth.

We are committed to building a diverse and inclusive workplace. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, or veteran status.