Senior C# Developer - Head of Core Platforms | Hedge Fund | London in City of London

The Client
Our client is a highly regarded discretionary investment manager with a strong focus on data-driven decision making. They operate with a small, agile structure and are recognised for their commitment to excellence in trading and technology. Their in-house technology function spans IT infrastructure, software development, and quantitative analysis, supporting all aspects of market data processing and trading activity. The environment is fast-paced, collaborative, and highly technical, where code quality, performance, and low-latency systems are top priorities. Engineers work across domains, contribute to architectural discussions, and help shape scalable, robust systems.

The Role
The client is embarking on a major initiative to unify and expand their core systems, bringing more of this capability in-house. As Head of Core Platform, you will lead this transformation—designing, planning, and implementing the evolution of the core technology stack to create a strong foundation for future growth. This is a hands-on leadership role. You will develop and consolidate systems, write software, guide a team of developers, and take ownership of several critical platforms. This includes an in-house C# PnL and Risk system that performs real-time portfolio valuation, alongside other components that will be integrated into a cohesive, modernised core platform. You will work closely with senior stakeholders including the CTO, COO, Head of Operations, and Project Management.

Candidate Profile

• Domain Expertise
  Strong background in fixed-income trading systems
  Knowledge across front-, middle-, and back-office workflows
  Demonstrable expertise in:
  Repo trading and lifecycle management
  Post-trade operations, clearance, and settlement
  Margin and collateral management
  Experience building systems that capture bond and swap (interest rate and FX) cashflow events
  Understanding of accrual (trade date) and realised (settlement date) accounting reconciliations
  Particular interest in candidates with Fixed Income and Rates experience
• Technical Skills
  Strong computer science fundamentals
  Hands-on development experience in:
  C# and .NET (essential for this role)
  Python within quant or data environments
  The client will also consider exceptional engineers from other OOP backgrounds such as C++, Java, or Go
  Familiarity with UI technologies such as WinForms, WPF, Blazor Hybrid, and Blazor Web
• Leadership & Approach
  Experience working in front-office or trading-technology environments, or on business-critical systems
  Ability to lead by doing—hands-on while guiding a team
  Pragmatic, delivery-focused mindset
  Commitment to high-quality engineering practices and low-latency, high-performance systems
  Low-ego, high-performing self-starter who values ownership, teamwork, and delivering commercial, pragmatic solutions

Why Apply
This is a rare opportunity to take ownership of a mission-critical transformation within a high-performing investment manager. You’ll shape the architecture, engineering standards, and long-term technical direction of the firm, working in a collegiate environment where ideas matter and technical excellence is valued. As a long-standing recruitment partner to this team, we can provide deep insight into the role, expectations, and culture, ensuring you have a clear and accurate understanding of the opportunity.