Senior Software Engineer – Execution & Order Management Systems

Senior Software Engineer | ~£950/day Outside IR35 | 6-months initial contract | London

Industry: Trading
Location: London – 4 days in office
Job Type: Contract – 6-month initial

Our client is building the next generation of execution and order management (EMS/OMS) infrastructure for global commodities trading. You will join a small, fast-moving engineering team designing and delivering a cloud-native trading platform from the ground up, tightly integrated with risk, pricing, and market data systems to support high-performance trading environments.
This is a senior, hands-on role for an engineer who wants end-to-end ownership – from low-level protocol integration through to distributed execution services and trader-facing tooling.

What You’ll Be Doing

• Design and build core components of a modern EMS/OMS platform, including order routing, order lifecycle management, venue connectivity, and execution analytics.
• Implement and maintain FIX protocol and venue-specific integrations across exchanges, brokers, and liquidity providers in commodities markets.
• Develop low-latency, distributed execution services with a strong focus on correctness, resilience, and performance under load.
• Collaborate closely with traders, quants, and risk engineers to translate trading workflows and execution strategies into robust production systems.
• Ensure seamless integration with risk systems, including pre-trade checks, position tracking, and post-trade processing.

Requirements
Essential

• Proven experience building execution systems and/or order management systems in production.
• Strong systems engineering fundamentals, including concurrency, distributed systems, networking, performance, and correctness under pressure.
• Production experience in at least one of C++, Rust, or Python, with willingness to work across multiple languages.
• Demonstrated ability to deliver production systems with a strong bias towards shipping, iteration, and user feedback.
• Comfortable working in a collaborative environment with direct engagement between engineers, traders, and quants.
• Experience working in cloud-native environments, particularly Kubernetes-based architectures.
• Familiarity with distributed data and event-driven systems (e.g. Kafka-style messaging patterns).
• Experience with observability, monitoring, testing, and production incident response in live systems.

Highly Desirable

• Experience in commodities markets (energy, metals, agriculture, freight) or other complex, multi-venue asset classes.
• Deep understanding of the FIX protocol, including session handling, message customisation, and venue-specific behaviour.
• Experience with algorithmic trading systems, smart order routing, or execution algorithm development.
• Exposure to real-time risk systems, including pre-trade controls and position/PnL infrastructure.
• Experience with columnar databases such as ClickHouse.