Senior React Engineer - £700 - £800 p/day – On-site (Central London)
Overview
We are hiring a Senior React Engineer to join a high-performance technology team within a leading financial services organisation operating in the oil and energy derivatives space. The business runs a cutting-edge electronic trading platform that serves both internal trading teams and external clients, offering low-latency, highly reliable trading access via a modern UI.
We are looking for a self-starter who takes ownership of technical challenges and delivers robust solutions, with the ability to work under pressure in a fast-moving trading environment. You must also be a collaborative team player who communicates clearly and contributes to a high-quality engineering culture.
Role & Responsibilities
* Design, build, and maintain a React/TypeScript trading UI, delivering real-time streaming data and a seamless user experience
* Integrate the UI with RESTful and streaming APIs (built in Rust and Python)
* Own performance improvements across dashboards, widgets, and live data visualisation
* Collaborate with QA and DevOps to enhance automated testing and deployment pipelines
* Lead efforts in securing, scaling, and monitoring the frontend environment
* Use observability tools (Prometheus, Grafana, Loki) to monitor UI health and performance
* Drive UI architectural decisions, performance benchmarking, and best practice implementation
Essential Skills and Experience
* Degree in Computer Science, Engineering, or a related field
* 5+ years of experience in frontend/UI engineering, with a focus on performance and scale
* Deep expertise in React, TypeScript, and JavaScript
* Strong understanding of WebSocket integration, low-latency data streaming, and threading
* Experience troubleshooting data-heavy UIs and optimising load times
* Familiarity with tools like Redis, Kafka, and cloud platforms such as Azure or AWS
* Proficient in Git and modern source control workflows
* Knowledge of performance diagnostics (e.g. Google PageSpeed Insights) and responsive UI optimisation
Desirable Skills and Experience
* Experience deploying apps to the Apple App Store
* Knowledge of web security best practices and cyber threat mitigation
* Familiarity with microservices and REST API architecture
* Exposure to Infrastructure as Code tools (e.g. Terraform)
* Experience working with real-time trading or data visualisation platforms
Package:
* Initial 12 month contract (high possibility of extension)
* Up to £800 p/day (dependent on level of experience)
* Outside IR35
* On-site (Central London)