Senior Frontend Engineer

London Stock Exchange Group

London, England, GBFull-time2026-10-04 → 2026-11-10

Core

Designing and maintaining a JavaScript SDK for secure authentication and identity management integration.

Role type

Senior IC frontend engineer (SDK development)

Builds

JavaScript SDKs for client applications

Domain

Financial markets infrastructure / Identity & Access Management

Required skills

React, TypeScript, modern JavaScript, SDK design, OAuth2, OpenID Connect, CI/CD pipelines, automated testing, frontend performance optimization, cross-browser compatibility, accessibility standards

Preferred skills

Developer experience (DX), clean code, automation, continuous improvement

Technologies

React, TypeScript, Secure Token Service

Responsibilities

Own and maintain a JavaScript SDK built with React and TypeScript; Design intuitive, developer-friendly APIs that abstract complex authentication flows; Ensure the SDK is secure, performant, and easy to integrate; Collaborate with backend engineers to align SDK functionality with evolving identity protocols; Build automated tests and CI pipelines; Write clear documentation and sample apps

Seniority

Senior, hands-on IC

About London Stock Exchange Group

LSEG (London Stock Exchange Group) is more than a diversified global financial markets infrastructure and data business. We are dedicated, open-access partners with a commitment to excellence in delivering the services our customers expect from us. With extensive experience, deep knowledge and worldwide presence across financial markets, we enable businesses and economies around the world to fund innovation, handle risk and create jobs. It's how we've contributed to supporting the financial stability and growth of communities and economies globally for more than 300 years. Through a comprehens