Lead Front-End Engineer (up to £175k)

Dex; Greater London; On-site; GBP 90,000 - 130,000; Full time

Job summary

Dex is building AI agents to automate complex financial workflows and deliver client-ready documents at unprecedented speed. As Lead Front-End Engineer, you will own the front-end craft across the product, defining patterns and guidelines that all engineers follow, including agentic tooling interfaces.

You will set the rules for how AI agents interact with the UI, ensuring quality scales with a rapidly growing platform. This is a rare opportunity to shape how, not just what, we build.

Qualifications

• Deep front-end fundamentals and understanding of what happens under the hood.
• Proven experience with multiple front-end frameworks and their trade-offs.
• Strong performance engineering instincts and bottleneck diagnosis skills.
• Exceptional architecture and systems design judgment for scalable front-end apps.
• Expert-level TypeScript experience.

Responsibilities

• Define and evangelize front-end architectural patterns and best practices across a full-stack engineering team.
• Establish the UI/UX guidelines and component libraries for human-coded and AI-generated interfaces.
• Drive performance engineering initiatives and implement systemic solutions.
• Collaborate with product and design to translate complex financial workflows into intuitive UX.
• Mentor engineers on front-end fundamentals and framework trade-offs.

Skills

Front-end fundamentals

TypeScript

Architecture & design

Performance debugging

Mentoring

Tools

React

Angular

Vue

Job description

This company builds AI agents that automate complex financial workflows, generating client-ready documents 20x faster than traditional methods. They're transforming how major financial institutions operate, backed by leading investors in one of the largest Series A rounds in the sector. They are one of the fastest-growing enterprise AI platforms globally.

This isn't a feature-shipping role. As a Lead Front-End Engineer, you'll own the front-end craft across the entire product, defining the patterns and guidelines that every engineer — even those working on agentic tooling — codes against. You'll set the rules for how AI agents interact with the UI, ensuring quality scales at the pace of a rapidly growing company. This is a rare seat for someone who wants to shape the how, not just the what.

The work

• Define and evangelize front-end architectural patterns and best practices across a full-stack engineering team.
• Establish the UI/UX guidelines and component libraries that ensure consistency and quality for both human-coded and AI-generated interfaces.
• Drive performance engineering initiatives, identifying root causes of slowness and implementing systemic solutions.
• Collaborate with product and design to translate complex financial workflows into intuitive, high-performance user experiences.
• Mentor engineers on front-end fundamentals, advanced techniques, and the trade-offs of different frameworks and tools.

What You Bring

• Deep front-end fundamentals; you understand what's happening under the hood, beyond just framework-specific knowledge.
• Proven experience with multiple front-end frameworks and tools, able to articulate their trade-offs.
• Strong performance engineering instincts, with a track record of diagnosing and solving complex performance bottlenecks.
• Exceptional architecture and systems design judgment for scalable, maintainable front-end applications.
• Expert-level TypeScript experience.