Senior Rapid Application Developer ***Hybrid, 3 days a week in the office 2 days remote*** About the Company – Senior Rapid Application Developer (Financial Services, FinTech, Trading, Low Latency, C++, Linux) My client is a leading, fast-growing exchange based in the City of London, operating at the cutting edge of European equity markets. They are an innovative and dynamic organisation working with sophisticated technology and genuinely interesting infrastructure. Their culture is built around trust, collaboration and accountability — moving quickly, supporting one another, and taking shared ownership of both successes and lessons learned. Their values shape how they work every day: Win as One – Collaborate, share knowledge and celebrate collective success. Disrupt Positively – Challenge the status quo and find smarter, better ways of working. Find Joy – Take pride in what you do and enjoy the challenge. Act with Honour – Do the right thing with integrity and respect. You'll join a supportive, ambitious and diverse team where ideas are encouraged and innovation is part of the DNA. They welcome talented people from all backgrounds and give engineers the opportunity to make a genuine impact. Job Overview – Senior Rapid Application Developer (Financial Services, FinTech, Trading, Low Latency, C++, Linux) In this role you will be working with the Product, Infrastructure, QA, and Operations teams to solve complex problems at speed. Unlike our Low Latency team who build the exchange engine itself, the RAD (Rapid Application Development) team lives at the intersection of troubleshooting, innovation, and operational efficiency. You'll be investigating the toughest production issues, validating new trading technology approaches through rapid prototyping, and building the internal tools and test frameworks that keep running smoothly. You'll be part of a small, high-impact team that combines detective work with creative engineering. One day you'll be diagnosing an intermittent issue in how we handle high-volume order processing; the next, you'll be building a POC for a new trading feature or designing a performance test suite that simulates real market stress. You thrive in environments where problems are ambiguous, priorities shift quickly, and your ability to communicate findings clearly to non-technical teams (QA, Product, Sales) is as important as the code you write. To succeed as a Senior RAD Engineer, you will be a proponent of agile principles and modern software best practices. You can produce detailed technical work in OOP and collaborate effectively with other development teams to produce code of high quality. Ideally, you will have worked in critical systems development and have direct experience investigating and resolving production issues in high-performance environments. You should be comfortable with operational thinking, understanding not just what systems do, but why they fail and how to prevent it. Responsibilities and Duties – Senior Rapid Application Developer (Financial Services, FinTech, Trading, Low Latency, C++, Linux) Lead rapid prototyping and validation efforts: Design and implement proof-of-concept solutions for new trading algorithms and system approaches, with emphasis on speed-to-market and iterative feedback from stakeholders. Drive troubleshooting investigations: Investigate complex production issues, performance anomalies, and system failures; establish reproducible test cases and diagnostic harnesses to validate root causes; communicate findings clearly to non-technical teams and document root causes for the broader engineering team. Build internal tools and frameworks: Develop tools that improve operational efficiency, such as test suites, performance benchmarking frameworks, reproduction environments, diagnostic utilities, and internal dashboards that enable Ops and QA teams to resolve issues faster and validate fixes reliably. Mentor mid-level RAD engineers: Provide technical guidance and code review for junior team members; help escalate issues appropriately and develop their investigative and prototyping skills. Establish and maintain RAD engineering standards: Champion best practices for MVP development, testing, deployment automation, and documentation; ensure RAD-produced code meets security and reliability standards despite the emphasis on speed. Apply deep technical analysis: Use computer science principles, engineering techniques, and mathematical analysis to break down complex problems in trading technology, market data flows, and system performance. Participate as a Subject Matter Expert: Review and advise on software components, system designs, and architectural decisions; act as the voice of operational realities in engineering discussions. Skills and Experience – Senior Rapid Application Developer (Financial Services, FinTech, Trading, Low Latency, C++, Linux) Essential 10+ years professional development experience with C++11 or later, building performant, scalable applications in production environments. 6+ years hands-on experience with networking fundamentals (UDP, multicast, TCP, etc.), messaging systems, and algorithmic problem-solving. 6+ years working on Linux systems, including kernel concepts, system tuning, and debugging tools (gdb, strace, perf, etc.). Linux systems and debugging: Comfortable with system-level investigation and performance analysis. Proven troubleshooting and investigative skills: Demonstrated ability to diagnose complex issues in production systems, whether via logs, memory dumps, or instrumentation, and communicate findings clearly to both technical and non-technical audiences. Expert in creating reproducible test cases: Skilled at building reliable test environments, isolating issues, and creating frameworks that help others validate fixes and prevent regressions. Strong understanding of modern development best practices: Continuous integration, automated testing, code review discipline, and version control workflows. Kanban and CI/CD: Comfortable with Kanban workflow, continuous integration, Jira, and rapid iteration cycles. Git and version control: Professional-grade proficiency. SQL: Ability to query and analyse data from our systems. Experience delivering under time pressure: Ability to prioritize effectively, ship MVPs quickly, and iterate based on feedback without perfectionism compromising progress. Proficient with AI tools in development: Comfortable using LLMs, coding assistants, and AI-powered tools to enhance productivity, debug code, generate documentation, and solve problems faster. Desired – Senior Rapid Application Developer (Financial Services, FinTech, Trading, Low Latency, C++, Linux) Python development proficiency: Strong ability to write automation scripts, diagnostic tools, and performance analysis scripts in Python. Shell scripting (Bash): For system-level automation and analysis. Performance analysis and optimization: Experience with profiling tools (perf, flame graphs, etc.) and track record of identifying and fixing performance bottlenecks. Experience building test infrastructure: Previous work on test frameworks, load testing suites, or performance benchmarking systems. Capital markets knowledge: Familiarity with exchange technology, FIX protocols, market data formats, or trading workflows. Docker/containerization basics: Growing relevance for deployment and testing. QuestDB or Dolt: Time-series or version-controlled database experience. Mindset and Methodology Operational mindset: You think about systems not just from a code perspective, but from "how will this be operated and what could go wrong?" You understand that production incidents are learning opportunities. Comfortable with ambiguity: RAD work often starts without a clear specification. You're skilled at gathering requirements, validating assumptions, and delivering value incrementally. Strong communicator: You can explain technical findings to non-technical stakeholders without dumbing down the substance. Your diagrams, summaries, and postmortems help the whole organization learn. Excellent team player: You collaborate across silos (Product, Infrastructure, Ops) and help other teams succeed, not just your own. Autonomous yet collaborative: You drive investigations independently but escalate proactively when needed. You know when to ask for help and when to dig deeper. Delivers incrementally: You ship fast and iterate. You understand that a 70% solution delivered today is often better than a perfect solution delivered next month. You recognize that validation and feedback drive better outcomes than endless upfront planning. Drive to solve complex problems: Above all, you're energized by the challenge of diagnosing the difficult bugs and building tools that make the platform more reliable and efficient. TPBN1_UKTJ
Senior Rapid Application Developer employer: REC SOLUTIONS LIMITED
Join a leading exchange in the City of London, where innovation and collaboration are at the heart of our culture. As a DevOps Engineer, you'll work with cutting-edge technology in a supportive environment that values integrity and shared success, offering ample opportunities for professional growth and the chance to make a meaningful impact in the fintech space. With a focus on continuous learning and development, this role is perfect for those eager to deepen their expertise while contributing to a dynamic team.
