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# Principal Software Engineer

- **Company:** TP ICAP
- **Location:** Belfast, United Kingdom
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** .NET Framework, C Sharp (Programming Language), Software Quality, Relational Databases, Strategies of Testing, TypeScript, WebSocket, Enterprise Software Applications, ReactJS, Grafana, Caching, Technical Debt, Backend, Low Latency, Playwright, Real Time Data, Graphql, Front End Software Development, React Redux, Api Design, JestJS
- **Published:** November 11, 2026
- **Apply:** https://www.indeed.com/viewjob?jk=d898b5fa365429e2

## About the Role

* Deep React + TypeScript expertise - you've architected large-scale applications and made structural decisions you can defend
 * Strong experience with Redux in complex, data-intensive UIs (sagas, selectors, normalised state, performance at scale)
 * Proven ability to design and maintain monorepo architecture: package boundaries, dependency management, build orchestration with Turborepo/pnpm
 * Production GraphQL experience (Apollo Client) - schema design collaboration, caching strategies, subscriptions, codegen workflows
 * Experience defining and implementing testing strategies across unit, integration, and browser layers
 * Track record of improving developer experience: build performance, linting/formatting automation, CI pipeline optimisation
 * You've led technical migrations or platform upgrades without halting feature delivery
 * Experience setting up or evolving frontend observability (RUM, tracing, error budgets)
 * Strong communicator who can translate architectural decisions into clear rationale for engineers, product, and leadership

Desired

 * Experience with real-time data systems (WebSockets, streaming updates, high-frequency UI rendering)
 * Deep AG Grid expertise - custom renderers, virtual scrolling, enterprise modules at scale
 * Exposure to financial/trading platforms or latency-sensitive environments
 * Experience with Module Federation or micro-frontend architectures
 * Familiarity with feature flag systems (Unleash) and progressive rollout strategies
 * Backend awareness (C#/.NET, GraphQL resolvers, relational databases) sufficient to
 * collaborate on API design

## Description

You'll be the technical leader for a real-time trading platform used daily by brokers across Rates & FX desks. The frontend is a large-scale React/TypeScript monorepo - dense data grids, real-time pricing via WebSocket and GraphQL subscriptions, and complex multi-panel layouts. You'll set the technical direction and make sure the architecture scales as the product grows.

You'll own the frontend architecture end-to-end: defining patterns, driving quality standards, removing technical debt, and enabling your team to ship confidently. You balance long-term technical vision with pragmatic delivery under real market conditions.

Role Responsibilities

 * Own the frontend architecture: define component boundaries, state management patterns, and data-flow contracts across a pnpm/Turborepo monorepo
 * Drive technical strategy for the platform - evaluate new tools, plan migrations, and make build-vs-buy decisions with clear rationale
 * Set and enforce engineering standards: testing strategy (Vitest, Playwright, MSW), code quality (Biome, Knip, dependency-cruiser), and observability (Grafana Faro, OpenTelemetry)
 * Design solutions for complex problems: real-time data rendering at scale, performant AG Grid configurations, efficient Redux-saga orchestration, and GraphQL subscription management
 * Lead technical delivery across multiple workstreams - unblock teams, resolve cross-cutting concerns, and ensure consistency across packages
 * Mentor and grow Senior Engineers through architecture reviews, pairing on hard problems, and creating space for others to make decisions
 * Collaborate with Product, Architects, and backend teams (C#/.NET, GraphQL BFF) to shape roadmap priorities and negotiate technical trade-offs