We have a current opportunity for a React Developer on a permanent basis. The position will be based in London. For further information about this position please apply. Requirements - 10 years engineering; 5 years building production React at scale - component lifecycle, rendering behaviour, and bundle architecture are instincts - TypeScript mastery in strict mode - complex generics, discriminated unions, conditional types, and type-safe API boundary design - Vite and modern build tooling; tree-shaking, chunk strategy, module federation, and build performance optimisation in CI - State management at scale: Zustand, TanStack Query, or equivalent; separation of server, client, and ephemeral UI state - High-frequency WebSocket data at tick-by-tick rates - back-pressure handling, dropped-frame detection, and reconnection strategy - Browser internals: rendering pipeline, layout/paint/composite lifecycle, memory profiling, GC pressure, and long-task detection - WebGL, Canvas, or custom rendering engine for high-density, real-time financial data visualisation - Design system ownership - token architecture, component API design, versioning strategy, and cross-team adoption at scale - Testing discipline: unit, integration, E2E (Playwright/Cypress), visual regression, and performance budget enforcement in CI - GraphQL or REST API co-design with backend teams; schema-first development and automated type generation - Track record of measurably improving engineering standards - patterns or tooling adopted org-wide - Cloud infrastructure - Azure preferred, AWS considered; IAM, managed services, automated and auditable deployment pipelines, secrets management To find out more about Huxley, please visit www.huxley.com Huxley, a trading division of SThree Partnership LLP is acting as an Employment Business in relation to this vacancy | Registered office | 8 Bishopsgate, London, EC2N 4BQ, United Kingdom | Partnership Number | OC387148 England and Wales