Java Developer – Front Office / Trading Systems

Join MARGO in the UK (London) – Perm & Contracting Opportunity. MARGO is a tech-native consultancy delivering high value-added IT expertise to the financial services industry. We specialise in complex software engineering environments where performance, robustness and scalability are critical: low latency systems, real-time data processing, distributed architectures and high-volume flows. Joining MARGO means working in demanding Front Office and Risk IT environments, while benefiting from a human-sized structure, close follow-up and tailor-made training paths.

Responsibilities

Design, develop and maintain high-performance Java applications; Work on real-time data processing (market data, pricing, orders, analytics); Implement multithreading and concurrency patterns adapted to performance-critical systems; Participate in system design, architecture discussions and technical specifications; Continuously optimise performance (latency, throughput, memory, GC behaviour); Contribute to the full software lifecycle: design, development, testing and release; Produce clean, maintainable and well-tested code; Participate in sprint planning, estimations and technical reviews; Collaborate closely with developers, quant and infrastructure teams; Provide 3rd line support on production systems when required; Participate in production releases including occasional out-of-hours interventions; Contribute to system stability, monitoring and incident prevention

Requirements

Strong experience as a Java Developer in performance-critical environments; Proven background in low-latency or high-throughput systems; Solid understanding of concurrency, threading and memory management; Experience working in Front Office, Trading or Risk IT environments; Comfortable working in Linux production environments; Clear communication and structured problem-solving skills; Expert-level Java; Multithreading & concurrency; Performance optimisation & low latency techniques; Garbage Collection awareness; Linux / UNIX environments; Distributed systems and messaging architectures; Performance monitoring and profiling tools

Nice to have

Event-driven or real-time systems; Messaging middleware (Kafka, Solace or equivalent); FIX or other market connectivity protocols; Networking fundamentals (TCP/IP, multicast); Exposure to one or more asset classes (Equities, Fixed Income, Commodities, FX, Derivatives); Experience in trading, pricing, risk or market data systems

Benefits

Access to multi-asset Front Office environments; Highly technical and challenging engineering assignments; Strong emphasis on skill development and long-term career progression; Human-sized consultancy with close support and high-quality missions; Tailor-made training paths