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# eFX Software Engineer (Java)

- **Company:** Harnham
- **Location:** Greater London, UK
- **Salary:** £160,000.0
- **Contract:** Permanent contract
- **Skills:** Java (Programming Language), Algorithmic Trading, Profiling, Linux, Distributed Systems, Fault Tolerance, Performance Tuning, Low Latency
- **Published:** August 26, 2026
- **Apply:** https://www.collegerecruiter.com/job/2815092265-efx-software-engineer-java

## About the Role

* Strong experience in low-latency Java within trading, eFX or electronic markets
 * Deep understanding of networking (TCP/UDP/FIX), Linux tuning, performance profiling
 * Background in designing high-performance architectures and distributed systems
 * Strong grasp of FX pricing, risk, and trading workflows
 * Experience working on mission-critical systems powering global trading
 * Highly technical culture with genuine ownership and impact
 * Flexibility in working hours and hybrid setup

## Description

eFX Software Engineer (Ultra-Low Latency Java)

Hybrid / Remote - London

Up to £160,000 + Bonus + Benefits

We're supporting a major financial services organisation hiring an eFX Software Engineer to build and optimise ultra-low-latency trading systems used across global FX markets. If you're a high-performance Java engineer who loves solving complex technical challenges at scale, this is a standout opportunity.

What you'll work on:

 * Engineering sub-40 μs latency eFX systems with high throughput and fault tolerance
 * Designing real-time pricing, risk and trading components
 * Evolving low-latency Java patterns (lock-free, low-GC, CPU/cache optimisation)
 * Working closely with quants, traders, architects and senior engineers
 * Influencing technical strategy across distributed, performance-critical systems

What we're looking for:

 * Strong experience in low-latency Java within trading, eFX or electronic markets
 * Deep understanding of networking (TCP/UDP/FIX), Linux tuning, performance profiling
 * Background in designing high-performance architectures and distributed systems
 * Strong grasp of FX pricing, risk, and trading workflows
 * Experience working on mission-critical systems powering global trading
 * Highly technical culture with genuine ownership and impact
 * Flexibility in working hours and hybrid setup


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