[Hiring] C++ Software Engineer @Reactive Markets

Role Description

We're looking for a C++ Software Engineer who wants to build low-latency trading infrastructure on Linux. You'll work on the core components of our Switchboard trading platform — pricing engines, connectivity gateways, market-data systems, and the messaging layer that ties them together.

This is not a role where you write code and throw it over a wall. You build it, you test it, you deploy it, you support it in production, and you improve it. Our engineers own the full lifecycle — from design through to operational excellence. When something breaks at 4pm on a Friday, you're part of the team that investigates and fixes it.

Occasional hours outside the normal working day are required for production releases, scheduled maintenance windows, and Level 3 support during critical incidents. We keep this to a minimum and recognise the commitment — but owning a production trading platform means being there when it matters.

What You'll Work On

• Modern C++20 and Go on Linux — a modern software stack based on open source
• Cloud-native infrastructure on AWS with colocation in key data centres
• Microsecond-level latency optimisation and high-throughput messaging
• Market-data and reference-data pipelines across multiple asset classes
• FIX protocol integrations with global banks and liquidity providers
• Observability and monitoring — dashboards, alerting, and metrics that make system behaviour visible
• Production systems that handle real money — reliability is not optional

Qualifications

• Strong C++ with Linux systems programming (3+ years)
• Comfortable working close to the metal — you understand what's underneath your code
• Experience with performance-sensitive systems (profiling, optimisation, deterministic behaviour)
• Familiarity with networking fundamentals (TCP/UDP, socket programming)
• Go experience is a strong bonus — we use Go extensively for microservices and command-line tooling
• Python for scripting, automation, testing, and data analysis
• Git and shell scripting
• Experience in financial services or trading technology is a plus but not essential

Requirements

• You ship.
• You're delivery-focused — you iterate, you improve, you get things into production
• You own it.
• When you build something, you take responsibility for its behaviour in production.
• You write things down.
• Documentation is not an afterthought — it's how we scale knowledge across a distributed team.
• You communicate.
• Clear, proactive communication — especially when things go wrong — is essential
• You care about quality.
• You write clean, testable code.
• You embrace AI tooling.

Benefits

• Real problems — trading systems where performance is measured in microseconds, not user clicks
• An excellent team — senior engineers who care about craft, collaborate openly, and hold each other to high standards
• Ownership — small teams, clear accountability, direct impact on the platform and our clients
• Competitive package — up to 30 days leave + bank holidays, private health insurance, pension, life insurance, dental/optical cashback, cycle to work, socials and offsites
• Remote-friendly — work from home with flexibility
• Sustainable pace — we work hard, but we don't burn people out
• Growth — career progression to senior roles, performance specialisation, or technical leadership

Our Hiring Process

• Stage 1: Initial Conversation with Talent Acquisition (Video call, ~30-45 minutes)
• Stage 2: Hiring Manager Conversation with the relevant team lead or hiring manager (Video call, ~60 minutes)
• Stage 3: Technical Interview with two members of the relevant engineering team (Video call, interactive session, ~60 minutes)

How to Apply

Please apply directly via this job posting — all applications, including those submitted via LinkedIn, are managed through our applicant tracking system.