Founding Frontend Engineer

Salary: £75,000 - 90,000 per year

Requirements:

• Strong commercial experience as a front end developer, delivering production web applications.
• Excellent JavaScript and TypeScript skills, with strong experience building UI with React.
• Solid HTML5 and CSS skills, including building responsive interfaces that work well across devices and browsers.
• Experience working with modern web application patterns, including server-side rendering or similar techniques and performance-minded UI delivery.
• Experience building enterprise scalable applications against REST APIs.
• Familiarity with common architectural patterns and building maintainable component-based applications.
• Nice to have: experience at an early-stage startup.
• Nice to have: experience using AI coding tools effectively.
• Nice to have: experience building data-heavy applications such as dashboards, tables, or real-time updates.

Responsibilities:

• Own the full frontend surface from design system foundations to performance to deployment.
• Translate UI/UX designs into clean, efficient, and maintainable code.
• Develop accessible and high-performing user interfaces across devices.
• Optimise application performance and ensure cross-browser compatibility.
• Identify, troubleshoot, and resolve front-end issues efficiently.
• Make decisions on authentication strategies and secure session/token approaches such as JWT, JWE, and token rotation.
• Collaborate with designers, developers, and stakeholders to deliver seamless digital experiences.
• Enforce and maintain best practices in frontend development, including code quality, testing, and performance optimisation.

Technologies:

• AI
• CSS
• Frontend
• HTML5
• JWT
• JavaScript
• REST
• React
• Security
• TypeScript
• Web
• UX UI Design

More:

We are a leading AI security start-up building an adaptive security layer designed to detect and respond to evolving threats in real time. As our Founding Frontend Engineer, you will take complete ownership of our frontend stack and help shape the principles and values we uphold in frontend engineering now and into the future. You will work with a talented engineering team on our core offering, building the user portal that is the first thing customers see when engaging with our product. We offer a base salary of £80,000 - £90,000, an employee matched pension plan, a stock option package, a wellness budget, and monthly socials.

last updated 30 week of 2026