Lead C++ / Java Developer

London Stock Exchange Group; Greater London; On-site; GBP 120,000 - 180,000; Full time

Job summary

London Stock Exchange Group invites a Lead Software Engineer to design, build, and operate mission-critical FX matching platforms using C++ and Java. You will focus on low-latency, high-throughput distributed systems and own technical delivery for key components.

You will collaborate with Product, QA, SRE, and Architecture teams to translate business requirements into robust technical solutions, mentor peers, and help evolve platform standards and engineering patterns.

Qualifications

• Bachelor's degree required in CS/Engineering or equivalent.
• 10+ years of software engineering experience.
• Experience delivering low-latency, high-throughput distributed systems.
• Proven FX, trading, or matching platform delivery.

Responsibilities

• Design, develop, and maintain C++ and Java services for FX matching.
• Own delivery for key platform components with architectural alignment.
• Build low-latency, high-availability systems handling large volumes.
• Collaborate with Product, QA, SRE, and Architecture teams.
• Provide mentoring and code reviews across teams.

Skills

C++

Java

Distributed systems

Low latency

Education

Bachelor's degree in Computer Science, Engineering, or equivalent

Tools

Linux

CI/CD pipelines

Build systems

Job description

## Lead C++ / Java DeveloperApplylocations: London, United Kingdomtime type: Full timeposted on: Posted Todayjob requisition id: R0119301**ABOUT US:**LSEG (London Stock Exchange Group) is more than a diversified global financial markets infrastructure and data business. We are dedicated, open-access partners with a dedication to excellence in delivering the services our customers expect from us. With extensive experience, deep knowledge and worldwide presence across financial markets, we enable businesses and economies around the world to fund innovation, manage risk and create jobs. It’s how we’ve contributed to supporting the financial stability and growth of communities and economies globally for more than 300 years. Through a comprehensive suite of trusted financial market infrastructure services – and our open-access model – we provide the flexibility, stability and trust that enable our customers to pursue their ambitions with confidence and clarity.LSEG is headquartered in the United Kingdom, with significant operations in 70 countries across EMEA, North America, Latin America and Asia Pacific. We employ 25,000 people globally, more than half located in Asia Pacific. LSEG’s ticker symbol is LSEG.**OUR PEOPLE:**People are at the heart of what we do and drive the success of our business. Our culture of connecting, creating opportunity and delivering excellence shape how we think, how we do things and how we help our people fulfil their potential. We embrace diversity and actively seek to attract individuals with unique backgrounds and perspectives. We break down barriers and encourage teamwork, enabling innovation and rapid development of solutions that make a difference. Our workplace generates an enriching and rewarding experience for our people and customers alike. Our vision is to build an inclusive culture in which everyone feels encouraged to fulfil their potential.We know that real personal growth cannot be achieved by simply climbing a career ladder – which is why we encourage and enable a wealth of avenues and interesting opportunities for everyone to broaden and deepen their skills and expertise. As a global organisation spanning 70 countries and one rooted in a culture of growth, opportunity, diversity and innovation, LSEG is a place where everyone can grow, develop and fulfil your potential with meaningful careers.**ROLE SUMMARY:**The Lead Software Engineer is a hands-on individual contributor responsible for designing, building, and operating mission‐critical FX market infrastructure and matching platforms using C++ and Java. The role focuses on low‐latency, high‐throughput distributed systems with strict availability, resiliency, and data integrity requirements.This role owns technical outcomes for complex components and services, influences architecture and platform evolution, and provides deep expertise across development, testing, and production support. While not a line‐management role, it carries strong expectations for technical leadership, mentoring, and collaboration across engineering, architecture, and product teams.**WHAT YOU'LL BE DOING:*** Design, develop, and maintain C++ and Java services supporting FX matching and trading workflows.* Own technical delivery for key platform components, ensuring alignment with LSEG architectural principles, performance standards, and operational controls* Build and evolve low‐latency, high‐availability systems handling high message volumes and time‐critical processing.* Ensure systems meet non‐functional requirements, including latency, throughput, resiliency, fault tolerance, security, and observability* Contribute to system and solution architecture, participating in design reviews and providing pragmatic input on scalability and operability.* Work closely with Product, QA, SRE, and Architecture teams to translate business requirements into robust technical solutions.* Diagnose and resolve complex issues across production, QA, and client environments, including root‐cause analysis of cross‐system failures.* Improve code quality and maintainability through clean design, automated testing, performance tuning, and controlled refactoring.* Integrate and manage dependencies on messaging platforms, data distribution systems, and upstream/downstream market infrastructure.* Evaluate and adopt suitable open‐source and third‐party technologies, ensuring they meet regulatory, security, and performance requirements.* Provide technical mentoring through code reviews, design discussions across teams.* Ensure adherence to SDLC standards, engineering best practices, and operational readiness requirements.* Contribute recommendations that influence platform standards, engineering patterns, and architectural direction across FX technology.**WHAT YOU'LL BRING:*** Bachelor’s degree in Computer Science, Engineering, or equivalent practical experience.* Strong hands‐on experience in both C++ and Java, delivering production-grade systems.* 10+ years of software engineering experience as a senior individual contributor.* Proven delivery experience with low‐latency, high‐throughput, distributed systems, ideally in FX, trading, or matching platforms.* Strong understanding of system integration, messaging, event-driven architectures, and data consistency.* Experience working across the full SDLC, including design, development, automated testing, deployment, and production support.* Familiarity with Linux, CI/CD pipelines, build systems, performance testing, and monitoring/alerting.* Practical experience with cloud platforms, containerization, and open‐source technologies.* Excellent problem-solving skills and the ability to influence technical outcomes without formal authority* Up-to-date with modern engineering practices, tools, and industry trends