Senior C++ Engineer - Low-Latency FinTech (Remote UK)

Reactive Markets Limited; United Kingdom; On-site; GBP 90,000 - 140,000; Full time

Benefits offered by this job

Remote-friendly

Job summary

Reactive Markets Limited in the United Kingdom is seeking a Senior C++ Software Engineer to shape the technical direction of our Switchboard trading platform. You will work on pricing engines, connectivity gateways, market-data systems, and the messaging layer with a direct influence on architecture.

This role requires ownership from design to production, mentoring juniors, and upholding reliability across production systems.

Qualifications

• Strong C++ with Linux systems programming (5+ years).
• Depth in distributed systems and network protocols (TCP/UDP, socket, FIX).
• Go experience is a strong bonus; used for microservices and tooling.
• Python for scripting, automation, testing, and data analysis.
• Experience with Git and shell scripting.

Responsibilities

• Modern C++20 and Go on Linux in a cloud-native stack.
• Optimise microsecond-level latency and high-throughput messaging.
• Work on pricing engines, connectivity gateways, market-data, and messaging layer.
• Provide architectural oversight, peer reviews, and mentorship.
• Own the full lifecycle from design through to production support.

Skills

C++

Linux systems programming

Low-latency

Distributed systems

Networking

Go

Python

Git

Tools

AWS

Job description

Reactive Markets Limited in the United Kingdom is seeking a Senior C++ Software Engineer to shape the technical direction of our Switchboard trading platform. You will work on pricing engines, connectivity gateways, market-data systems, and the messaging layer with a direct influence on architecture.

This role requires ownership from design to production, mentoring juniors, and upholding reliability across production systems.