Location: Leeds, West Yorkshire, Yorkshire, UKWe are looking for an experienced Senior Python Software Engineer to take ownership of an established trading-related application and drive its ongoing development. You will manage and enhance the existing codebase, deliver new features, ensure reliability and performance, and help evolve the system as the business grows.This is an excellent opportunity for someone who enjoys autonomy, technical responsibility, and working on low-latency, high-performance applications.What Youll DoMaintain, extend, and optimise an existing Python-based trading applicationAdd new features and improve current capabilities with a focus on performance, reliability and clean architectureBuild and optimise real-time pipelines handling high-frequency dataImprove latency, throughput, and reliability using profiling and performance engineeringWork with Redis, Azure VMs, and Anaconda environmentsImplement and maintain systems requiring millisecond-level timing precisionTroubleshoot production issues quickly during key market hoursCollaborate directly with the founder to shape technical direction and prioritiesIntegrate with market data feeds and brokerage/order-routing componentsEssential SkillsExpert-level Python developer (min. 5+ years professional python experience)Demonstrable experience with low-latency/high-throughput systems (e.g., real-time data processing, trading/market data, telemetry, adtech bidding, streaming systems, etc.)Strong understanding of asynchronous programming, multiprocessing, and performance optimisationExperience handling large volumes of fast-moving data with careful performance considerationsAbility to profile, measure, and improve performanceComfortable owning an existing codebase: refactors, architecture improvements, clean testsExperience with Redis and general database performance considerationsCompetent with Azure cloud environments (VMs, deployment, monitoring, etc.)Comfortable working independently, making architectural decisions, and maintaining high code qualityStrong engineering discipline: correctness, edge cases, careful time-handling, attention to detailUK-based and available for support during core market hours when neededDesirable SkillsExperience with algorithmic trading or market data systemsFamiliarity with Interactive Brokers TWS or other brokerage APIsExperience with distributed systems, message queues, or event-driven architecturesBackground in financial markets or fintechWhat We OfferCompetitive salary - negotiable based on experienceMostly remote, with some in-office collaboration days for coordination and planningYearly bonus based on company performanceThe chance to take significant ownership of a live, production-grade systemLong-term role with the opportunity to influence the roadmap and system designA lean environment with minimal bureaucracy and direct impactTPBN1_UKTJ