Principal Software Engineer - C#

TP ICAP Group Services Ltd; City Of London; On-site; GBP 120,000 - 180,000; Full time

Job summary

TP ICAP Group Services Ltd seeks a Principal Engineer to own the architecture, design and hands-on delivery of a desktop platform automating trading desk workflows. A high-visibility, player-coach role may evolve to include people management.

You will mentor teams, shape the technical direction of a greenfield project, and ensure hard latency budgets and robust, secure software across Windows desktop hosting web content. London-based, hybrid/onsite work expected.

Qualifications

• 10+ years in financial services building complex front-office trading systems.
• Proven technical leadership through multi-year delivery and governance.
• Hands-on experience across full software lifecycle, including AI-assisted coding.
• Excellent written and verbal communication in a matrix, global organisation.

Responsibilities

• Architect the desktop platform and deliver high-availability, low-latency code.
• Lead the greenfield project through design, build and production operation.
• Design for latency budgets, isolation, and secure least-privilege boundaries.
• Mentor team members and coordinate with offshore vendors.
• Drive AI-assisted development with governance and safety reviews.

Skills

C# / .NET

Leadership

React/TypeScript

Electron / Desktop apps

WPF

API design

Event-driven architecture

AI tools in development

Cloud platforms (AWS)

Latency optimization

Education

Degree in Computer Science, Engineering, Mathematics, Physics

Tools

ASP.NET Core

WebSocket / IPC

Electron / OpenFin

Bloomberg DAPI

FIX protocol

Job description

Role Overview

ICRV are seeking an exceptional Principal Engineer to own the architecture, design and hands‑on delivery of a desktop platform automating and streamlining trading desk workflows. This is a high‑visibility player‑coach role that may evolve to include formal people management.

Role Responsibilities

• Act as the primary hands‑on technical leader: architect the platform, write correctness‑critical code, and set the engineering bar through your own output.
• Own the technical direction of the ICRV greenfield project, developing high‑performance, scalable, and robust solutions from first principles through to production operation.
• Design for hard non‑functional requirements: latency and responsiveness budgets as acceptance criteria, crash containment, least‑privilege isolation between sub‑applications.
• Work effectively with a matrix management structure, taking designs through group‑wide governance while delivering business value and ensuring adherence to group wide technology standards and mandates.
• Mentor and coach other team members to achieve optimum performance and career growth.
• Leverage offshore staffing vendors effectively.
• Establish AI‑assisted development as a disciplined team practice using company‑wide tooling, workflow integration, and the review rigour that makes AI‑generated code safe to ship.
• Communicate technical trade‑offs clearly to trading, compliance, infrastructure and middle‑office stakeholders; manage risk and upset honestly.
• Identify and drive refactoring toward the target architecture as the platform grows.

Experience / Competences

• 10+ years in financial services building complex front‑office trading systems with demonstrated technical leadership through multi‑year delivery.
• Demonstrated success leading engineering teams through complex, multi‑year transformation programmes.
• Hands‑on experience across the full software development lifecycle.
• Practical experience using AI tools across the development lifecycle, including the review discipline for AI‑generated code.
• Excellent written and verbal communication; effective in a matrixed, global organisation; self‑motivated and proactive.
• Degree in Computer Science, Engineering, Mathematics, Physics, or a relevant analytical discipline.
• Domain knowledge: Understanding of relative‑value execution (cash/futures basis, calendar spreads, curve trades) and how that translates into workflow and system requirements.
• Familiarity with futures market structure (exchange, clearing, margining) and US Treasury market structure (cash bonds, primary dealers, settlement).
• Knowledge of futures clearing/margin systems (e.g. CME) and Treasury settlement rails.
• Experience with execution/order connectivity protocols (FIX or equivalent) in an interdealer, agency or execution‑desk context.
• Understanding of 24‑hour, multi‑region trading operations (follow‑the‑sun handover, timezone‑aware processing across London/New York/Singapore).
• Expert‑level C# /.NET (LTS): back‑end services with ASP.NET Core.
• Experience designing and delivering event‑driven, service‑oriented back‑end systems (message brokers, async workflows, API design) in a production trading environment.
• Experience building desktop applications that host web content (e.g. Electron, Tauri, or custom .NET host), comfortable with WebSocket bridges, local service APIs, or IPC mechanisms to connect web UIs with native desktop applications.
• Sufficient front‑end literacy (React, TypeScript, Node) to make architectural decisions, review code, and collaborate effectively with dedicated front‑end teams.
• Demonstrated ability to leverage coding agents in spec‑driven development workflows.
• Strong grasp of process isolation, information security, and identity/access management; experience with event‑driven messaging and least‑privilege service boundaries.
• Familiarity with modern build pipelines and tools.
• Experience designing within formal governance and architecture‑review frameworks.
• Desired experience with desktop interop frameworks and protocols (FDC3, OpenFin, or custom IPC/message‑bus implementations).
• WPF or other rich‑client .NET UI experience.
• Experience interfacing with third‑party desktop APIs (e.g. Bloomberg DAPI).
• Performance engineering: profiling and holding hard latency budgets.
• Experience with high‑throughput trade/market‑data processing at scale.
• Cloud platform experience (AWS or equivalent); containerisation and orchestration.
• Relational data and canonical/JSON data contract design.
• Design‑system principles and component‑library development.

Role Band & Level

Manager, 7 #LI-Hybrid #LI-DIR

Location

UK – 135 Bishopsgate – London