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# Senior Systems Design C++ Engineer

- **Company:** Selby Jennings
- **Location:** London, UK
- **Experience:** Expert
- **Salary:** £76,542.0
- **Contract:** Permanent contract
- **Skills:** Systems Engineering, C++ (Programming Language), Databases, Distributed Systems, Memory Management, Performance Tuning, Multithreading, High Performance Computing, Concurrency
- **Published:** September 16, 2026
- **Apply:** https://www.adzuna.co.uk/jobs/details/5885544806

## About the Role

* Background in systems, platform, or infrastructure engineering
 * Experience with multithreading, concurrency, and performance optimisation
 * Strong CS fundamentals and problem-solving skills
 * Ability to operate as a senior individual contributor

## Description

We're working with a leading quantitative investment firm seeking a Senior C++ Engineer to help build and optimise the simulation and research platforms used by researchers and portfolio managers to develop, test, and refine investment models. This is a hybrid role based in London (3 days in/2 days home).

This is not a trading or execution role. The focus is on large-scale systems engineering, performance optimisation, and research infrastructure.
What You'll Do

 * Develop and enhance mission-critical C++ platforms
 * Optimise system performance, scalability, and reliability
 * Work on low-level systems challenges including memory management, concurrency, and I/O optimisation
 * Collaborate with highly technical engineers and researchers
 * Take ownership of complex, long-lived platform components, The team is particularly interested in engineers from:
 * Big Tech
 * Infrastructure and platform engineering teams
 * Distributed systems or HPC environments
 * Database, storage, search, or compute platforms
 * Quantitative finance and research-focused technology firms

Why Join?

 * Work on business-critical research infrastructure
 * Challenging performance and systems engineering problems
 * Significant ownership and autonomy
 * Strong engineering culture
 * Collaboration with world-class researchers and engineers