Full job descriptionSoftware Developer, C++ / Electronic Trading
London | Hybrid | Permanent


Ncounter is supporting the growth of a specialist electronic trading technology team responsible for building and enhancing high-performance systems operating across global financial markets. We are looking for an experienced Software Developer with strong C++ skills and a background working on low-latency trading technology.
You’ll work on business-critical applications including matching engines, FIX gateways and real-time trading systems, where performance, availability and efficient processing are fundamental. This is a hands-on development role with considerable exposure to C++, alongside Java, Python and JavaScript within a predominantly Linux environment.


What you’ll be working on
• Designing and developing high-performance matching engines, FIX gateways and electronic trading applications
• Building low-latency, multithreaded systems using C++ and Java
• Processing real-time market and trading data through highly available systems
• Developing efficient in-memory data structures, lock-free queues and circular buffers
• Working with TCP/IP, UDP, multicast and other networking technologies
• Troubleshooting, profiling and optimising performance-critical production applications
• Supporting automated testing, DevOps practices and CI/CD pipelines
• Working closely with trading, product and infrastructure teams throughout the development lifecycle


What we’re looking for
• 5+ years of professional software development experience
• Strong C++ development skills, ideally alongside commercial Java experience
• Hands-on FIX protocol experience within electronic trading
• Experience building low-latency, high-frequency or performance-critical systems
• Strong Linux knowledge covering multithreading, sockets, IPC and system-level behaviour
• Good understanding of concurrency, memory management and in-memory optimisation
• Knowledge of NUMA architectures and performance-focused programming techniques
• Experience with networking protocols including TCP/IP, UDP, unicast and multicast
• Python, SQL and relational database experience would be useful
This is an opportunity to work close to the core of electronic trading, solving challenging engineering problems where software performance has a direct business impact.
If you have strong C++ engineering experience alongside FIX and low-latency trading systems, get in touch with Ncounter for a confidential discussion.