Algorithm Engineer

Senior FIX Connectivity & Algorithmic Trading Consultant – Capital Markets (Fintech)

  • Day Rate: €600 per day
  • IR35: Outside IR35
  • Contract: Initial 6 months (extension likely)
  • Location: Fully remote – EUR time zones (strong preference for South Africa)

This engagement sits at the sharp end of institutional trading technology. The client is a well-established capital markets participant undergoing a critical modernisation of its electronic trading stack, with a specific focus on FIX connectivity, low-latency execution and market-making infrastructure.

They are mid-way through a multi-phase transformation programme, replacing legacy FIX adapters and execution logic with a modern, high-performance Onix FIX-based architecture. This role exists because the work is business-critical — and they need senior, sellside experience to get it right.

The Role

This is a high-impact senior advisory engagement, working directly with trading, quant and technology leadership.

You will:

  • Own the end-to-end FIX adapter migration strategy from legacy ULLink into Onix FIX
  • Define architecture and execution logic for market-making, hedging and risk algorithms
  • Act as the authority on FIX connectivity, latency optimisation and order routing
  • Influence how trading engines are structured, benchmarked and deployed
  • Set standards for algorithm design, testing and performance validation
  • Work directly with front-office stakeholders to align technology with trading intent
  • Provide architectural direction without needing internal sign off or escalation

What We’re Looking For

  • Deep sell-side experience in electronic trading infrastructure
  • Strong hands on background with FIX connectivity (ULLink, Onix FIX or equivalent)
  • Proven experience designing market-making and hedging algorithms
  • Low-latency systems expertise (Java, GC tuning, memory management, threading)
  • Ability to operate autonomously in senior advisory environments
  • Comfortable presenting technical decisions to trading and senior stakeholders
  • South African capital markets exposure (JSE, local market structure) is a strong advantage

Why This Role

  • Direct influence on live trading architecture and execution performance
  • High-trust advisory role — you are brought in for judgement, not delivery volume
  • Close access to senior trading and quant leadership
  • Fully remote with CET / SAST overlap
  • Clear scope, urgency and decision-making authority

Apply

  • To apply – click the link or email Barry.Ansell@HarringtonStarr.com for a faster response

Job Details

Company
Harrington Starr
Location
London Area, United Kingdom
Hybrid / Remote Options
Posted