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Trading & Exchange TechnologyLive

Senior Rapid Application Developer

Confidential: European equities exchangeLondon (hybrid, two days)PermanentUp to £115,000 + performance bonus
C++LinuxProduction troubleshootingRapid prototypingPython

A senior C++ engineer for the small team that sits between the exchange engine and everyone who depends on it. You'll investigate the hardest production issues, prototype new trading features fast, and build the test and diagnostic tools that keep a live European equities venue running. Detective work and creative engineering in equal measure.

The work

This is not the team that builds the matching engine. The Rapid Application Development team lives where troubleshooting, prototyping and operational efficiency meet. One day you are diagnosing an intermittent issue in high-volume order processing. The next you are building a proof of concept for a new trading feature, or a performance test suite that simulates real market stress. Problems arrive ambiguous and priorities move quickly. Explaining what you found to QA, Product and Sales matters as much as the code you write.

What you'll be doing

  • Prototype and validate new trading features and system approaches quickly, iterating on feedback from stakeholders
  • Lead investigations into complex production issues, performance anomalies and failures, building reproducible test cases and diagnostic harnesses to prove root cause
  • Build the internal tools that help Operations and QA resolve issues faster: test suites, performance benchmarking frameworks, reproduction environments and dashboards
  • Mentor mid-level engineers on the team through code review and investigative technique
  • Set the team's standards for MVP development, testing and deployment automation, so speed never costs security or reliability
  • Act as the voice of operational reality in design and architecture discussions

What you'll need

Useful extras: Python and Bash for automation and diagnostics, profiling with perf and flame graphs, experience building test infrastructure, and familiarity with FIX, market data formats or trading workflows.

  • 10+ years building production applications in modern C++, C++11 or later
  • 6+ years with networking fundamentals (TCP, UDP, multicast), messaging systems and algorithmic problem-solving
  • 6+ years on Linux, including kernel concepts, system tuning and debugging tools such as gdb, strace and perf
  • A track record diagnosing complex production issues through logs, memory dumps or instrumentation, and explaining the findings to technical and non-technical people
  • Strong habits around CI, automated testing, code review, Git and Kanban, plus enough SQL to query and analyse system data
  • Comfort shipping an MVP under time pressure, and using AI coding tools to work faster

What happens next

We start with a confidential conversation to walk through the systems, the team and the kind of problems you would be solving before anything moves forward.

If it is a fit, you will get a straight read on the process and the comp. If it is not, I will tell you that too.