Lead Software Developer C# – Trading Systems
Location: London (City) – Hybrid / Remote Options
Our client is a growing global financial trading firm seeking a senior, hands-on Software Engineer to take ownership of our in-house trading and brokerage platforms.
This is a high-impact leadership role reporting directly to the CEO/COO, offering direct exposure to executive management and genuine influence over long-term technology strategy.
You will assume responsibility for a mission-critical trading system used daily across Europe, the US and Asia, playing a central role in stabilising, enhancing and modernising our core infrastructure.
The Role
This position combines:
- Hands-on development (C# / .NET)
- System architecture ownership
- Team leadership
- Business-facing engagement with traders and senior stakeholders
You will lead the technical roadmap of our trading and booking platforms while ensuring resilience, scalability and operational stability in a live trading environment.
Key Responsibilities
- Lead development and architectural direction of in-house trading systems
- Contribute hands-on to coding and system enhancement
- Oversee trade booking, lifecycle management, P&L and risk capture systems
- Support messaging, integrations and reporting infrastructure
- Provide senior-level production support in live trading environments
- Manage and mentor a small development team (with planned growth)
- Reduce key-person dependency through documentation and knowledge transfer
- Drive modernisation initiatives, including migration from legacy technologies
- Partner closely with trading teams and senior management
Technical Environment
- C#
- .NET Framework 4.7.2 (WinForms)
- Microsoft SQL Server
- RabbitMQ
- In-house FIX engine
- Microsoft Azure
- Azure DevOps
- Excel VBA-based tools
- Fully in-house developed systems
Experience Required
Essential:
- 7–10+ years software development experience
- Strong C# and .NET expertise
- Experience maintaining and evolving legacy systems
- Solid SQL Server and database design knowledge
- Experience within trading, brokerage or financial services environments
- Understanding of equity and/or derivatives trading workflows
- Experience leading technical teams
- Strong problem-solving capability in high-pressure environments
Highly Desirable:
- Trading platform or booking system experience
- FIX protocol knowledge
- Experience migrating WinForms to modern architectures
- Azure cloud architecture experience
- CI/CD and automation exposure
Profile
We are looking for someone who is:
- Commercially minded and pragmatic
- Comfortable operating with autonomy and high responsibility
- Able to balance production support with long-term strategic improvement
- Confident communicating with both technical and non-technical stakeholders
- Motivated to build sustainable, long-term system ownership
What We Offer
- Senior leadership position in a growing financial firm
- Direct reporting line to executive management
- Business-critical remit with genuine impact
- Competitive compensation package
- Flexible working arrangements
- Opportunity to shape the long-term technology strategy of a global trading platform