Senior Frontend Engineer in London

We are seeking a Senior Frontend Developer to join our Customers Identity & Access Management team at LSEG.

You will play a pivotal role in maintaining and evolving our Java Script SDK, a critical interface that enables secure authentication and seamless integration of our Authentication into client applications for our customers.

This role is ideal for someone who thrives in developer experience, SDK design, and security-focused frontend engineering.

Responsibilities

• Own and maintain a Java Script SDK built with React and Type Script, enabling secure integration with our custom Secure Token Service.
• Design intuitive, developer-friendly APIs that abstract complex authentication flows (OAuth2, Open ID Connect).
• Ensure the SDK is secure, performant, and easy to integrate across a wide range of frontend applications.
• Collaborate with backend engineers to align SDK functionality with evolving identity protocols and token flows.
• Build automated tests and CI pipelines to ensure quality, reliability, and backward compatibility.
• Write clear documentation and sample apps to support internal and external developers.
• Stay current with frontend security best practices and contribute to platform-wide improvements.
• What You’ll Bring
• Proven experience in frontend development with deep expertise in React, Type Script, and modern Java Script.
• Proven experience designing and maintaining SDKs or libraries used by other developers.
• Strong understanding of OAuth2, Open ID Connect, and secure authentication flows.
• Familiarity with CI/CD pipelines, automated testing, and versioning strategies for SDKs.
• Experience with frontend performance optimization, cross-browser compatibility, and accessibility standards.
• Passion for clean code, automation, and continuous improvement.
• Excellent interpersonal skills and a passion for developer experience and security.

Benefits

• Competitive compensation with performance-based rewards.
• A flexible hybrid work model that supports work‑life balance.
• Access to cutting‑edge tools and infrastructure to do your best work.
• Opportunities for continuous learning, including certifications, conferences, and internal mobility.
• A collaborative culture that values technical mastery, ownership, and innovation.
• The chance to work on a globally critical system that powers secure financial transactions across markets.
• Career Stage
• Manager
• Equal Opportunity Employer

We are proud to be an equal opportunities employer.

This means that we do not discriminate on the basis of anyone’s race, religion, colour, national origin, gender, sexual orientation, gender identity, gender expression, age, marital status, veteran status, pregnancy or disability, or any other basis protected under applicable law.

Conforming with applicable law, we can reasonably accommodate applicants’ and employees’ religious practices and beliefs, as well as mental health or physical disability needs.

#J-18808-Ljbffr