Senior Software Engineer (Python)

Were hiring a Senior Software Engineer (Python) - Trading Systems to own and evolve a production options trading system. It runs during market hours, ingests real-time market data, and requires profiling-led performance engineering to keep p50/p99 latency, jitter, and reliability within tight bounds.<br><br>Like the look of this opportunity Make sure to apply fast, as a high volume of applications is expected Scroll down to read the complete job description.<br>Youll take meaningful ownership day-to-day, partnering closely with the founder and the engineering team to prioritise work, ship improvements quickly, and keep the system fast, reliable, and correct.<br><br>Who this is for<br>This role is for engineers who have built and owned real-time, performance-critical systems.<br>It is not suitable for candidates whose experience is mainly web product development (frontend-heavy or CRUD backends).<br>Were looking for proven experience with measuring and improving p99 latency/jitter and operating systems during time-critical windows.<br>Must be based in the UK and with a legal right to work in the UK<br>Location : UK-based<br>Working style : Mostly remote, occasional in-person days for planning/coordination<br>Support : Availability during core market hours required<br><br>What Youll Do<br>Own and improve a production Python codebase that runs during market hours.<br>Build and optimise real-time market data pipelines (throughput, p50/p99 latency, jitter).<br>Do profiling-driven performance work across ingestion ? compute ? messaging ? consumers.<br>Improve reliability: freshness/staleness handling, safe degradation, back pressure, fault isolation.<br>Strengthen developer leverage: replay/simulation tools, regression tests, and debugging tooling.<br>Work with cloud infrastructure, deployment, monitoring, and incident response.<br>Collaborate directly with the founder and engineering team on architecture and roadmap.<br><br>Essential Skills<br>5+ years professional Python experience; youve shipped and owned production systems.<br>Built/owned a real-time / low-latency system (not batch ETL) with measurable performance goals.<br>Strong understanding of async + multiprocessing trade offs and performance profiling.<br>Comfortable owning an existing codebase: refactors, tests, architecture improvements.<br>Experience with messaging / event-driven systems and strong API/schema discipline.<br>Production ownership mindset: incidents, monitoring, and fast debugging when it matters.<br>UK-based preferred and able to support core market hours when required.<br><br>Desirable Skills<br>Interactive Brokers (TWS/IB Gateway) or similar brokerage/execution APIs.<br>Experience with trading, market data, or execution systems.<br>Experience designing safety constraints/guardrails in automated systems.<br><br>What We Offer<br>Competitive salary (negotiable) + performance-related bonus.<br>Mostly remote, with some in-office collaboration days for coordination and planning<br>Lean environment, direct impact on a live system. xwzovoh <br>High ownership and influence over system design and roadmap.