Frontend Engineer
Posted on Jul 10, 2026 by CV-Library
London, United Kingdom
IT
Immediate Start
£80k - £95k Annual
Full-Time
Founding Frontend Engineer
We're recruiting for a leading AI security start-up who are building an adaptive security layer designed to detect and respond to evolving threats in real time. As a Founding Frontend Engineer, you'll be responsible for developing, maintaining, and scaling their user portal - the first thing customers see when engaging with their product.
You'll also be crafting the principles and values the organisation upholds when doing frontend engineering now, and into the future. This is an opportunity to take complete ownership over their frontend stack, work with an incredible team of talented engineers, and to help build the future of their core offering.
Your Responsibilities
*
Owning the full frontend surface from design system foundations to performance to deployment.
*
Translating UI/UX designs into clean, efficient, and maintainable code.
*
Developing accessible and high-performing user interfaces across devices.
*
Optimising application performance and ensuring cross-browser compatibility.
*
Identifying, troubleshooting, and resolving front-end issues efficiently.
*
Decision making on authentication strategies and secure session/token approaches (e.g. JWT/JWE, token rotation).
*
Collaboration with designers, developers, and stakeholders to deliver seamless digital experiences.
*
Enforcing and maintaining best practices in frontend development, including code quality, testing, and performance optimisation.
You Should Have
*
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.
It Would Be Nice If You Have
*
Worked in an early-stage startup before and know what it feels like when there's no playbook.
*
Used AI coding tools and know how to get leverage from them without losing control of the codebase.
*
Built something data-heavy (dashboards, tables, real-time updates) and know where the performance traps are.
Benefits
*
£80,000 - £90,000 Base Salary
*
Employee Matched Pension Plan
*
Stock Option Package
*
Wellness Budget
*
Monthly Socials
We're recruiting for a leading AI security start-up who are building an adaptive security layer designed to detect and respond to evolving threats in real time. As a Founding Frontend Engineer, you'll be responsible for developing, maintaining, and scaling their user portal - the first thing customers see when engaging with their product.
You'll also be crafting the principles and values the organisation upholds when doing frontend engineering now, and into the future. This is an opportunity to take complete ownership over their frontend stack, work with an incredible team of talented engineers, and to help build the future of their core offering.
Your Responsibilities
*
Owning the full frontend surface from design system foundations to performance to deployment.
*
Translating UI/UX designs into clean, efficient, and maintainable code.
*
Developing accessible and high-performing user interfaces across devices.
*
Optimising application performance and ensuring cross-browser compatibility.
*
Identifying, troubleshooting, and resolving front-end issues efficiently.
*
Decision making on authentication strategies and secure session/token approaches (e.g. JWT/JWE, token rotation).
*
Collaboration with designers, developers, and stakeholders to deliver seamless digital experiences.
*
Enforcing and maintaining best practices in frontend development, including code quality, testing, and performance optimisation.
You Should Have
*
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.
It Would Be Nice If You Have
*
Worked in an early-stage startup before and know what it feels like when there's no playbook.
*
Used AI coding tools and know how to get leverage from them without losing control of the codebase.
*
Built something data-heavy (dashboards, tables, real-time updates) and know where the performance traps are.
Benefits
*
£80,000 - £90,000 Base Salary
*
Employee Matched Pension Plan
*
Stock Option Package
*
Wellness Budget
*
Monthly Socials
Reference: 225356139
https://jobs.careeraddict.com/post/113540938
Frontend Engineer
Posted on Jul 10, 2026 by CV-Library
London, United Kingdom
IT
Immediate Start
£80k - £95k Annual
Full-Time
Founding Frontend Engineer
We're recruiting for a leading AI security start-up who are building an adaptive security layer designed to detect and respond to evolving threats in real time. As a Founding Frontend Engineer, you'll be responsible for developing, maintaining, and scaling their user portal - the first thing customers see when engaging with their product.
You'll also be crafting the principles and values the organisation upholds when doing frontend engineering now, and into the future. This is an opportunity to take complete ownership over their frontend stack, work with an incredible team of talented engineers, and to help build the future of their core offering.
Your Responsibilities
*
Owning the full frontend surface from design system foundations to performance to deployment.
*
Translating UI/UX designs into clean, efficient, and maintainable code.
*
Developing accessible and high-performing user interfaces across devices.
*
Optimising application performance and ensuring cross-browser compatibility.
*
Identifying, troubleshooting, and resolving front-end issues efficiently.
*
Decision making on authentication strategies and secure session/token approaches (e.g. JWT/JWE, token rotation).
*
Collaboration with designers, developers, and stakeholders to deliver seamless digital experiences.
*
Enforcing and maintaining best practices in frontend development, including code quality, testing, and performance optimisation.
You Should Have
*
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.
It Would Be Nice If You Have
*
Worked in an early-stage startup before and know what it feels like when there's no playbook.
*
Used AI coding tools and know how to get leverage from them without losing control of the codebase.
*
Built something data-heavy (dashboards, tables, real-time updates) and know where the performance traps are.
Benefits
*
£80,000 - £90,000 Base Salary
*
Employee Matched Pension Plan
*
Stock Option Package
*
Wellness Budget
*
Monthly Socials
We're recruiting for a leading AI security start-up who are building an adaptive security layer designed to detect and respond to evolving threats in real time. As a Founding Frontend Engineer, you'll be responsible for developing, maintaining, and scaling their user portal - the first thing customers see when engaging with their product.
You'll also be crafting the principles and values the organisation upholds when doing frontend engineering now, and into the future. This is an opportunity to take complete ownership over their frontend stack, work with an incredible team of talented engineers, and to help build the future of their core offering.
Your Responsibilities
*
Owning the full frontend surface from design system foundations to performance to deployment.
*
Translating UI/UX designs into clean, efficient, and maintainable code.
*
Developing accessible and high-performing user interfaces across devices.
*
Optimising application performance and ensuring cross-browser compatibility.
*
Identifying, troubleshooting, and resolving front-end issues efficiently.
*
Decision making on authentication strategies and secure session/token approaches (e.g. JWT/JWE, token rotation).
*
Collaboration with designers, developers, and stakeholders to deliver seamless digital experiences.
*
Enforcing and maintaining best practices in frontend development, including code quality, testing, and performance optimisation.
You Should Have
*
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.
It Would Be Nice If You Have
*
Worked in an early-stage startup before and know what it feels like when there's no playbook.
*
Used AI coding tools and know how to get leverage from them without losing control of the codebase.
*
Built something data-heavy (dashboards, tables, real-time updates) and know where the performance traps are.
Benefits
*
£80,000 - £90,000 Base Salary
*
Employee Matched Pension Plan
*
Stock Option Package
*
Wellness Budget
*
Monthly Socials
Reference: 225356139
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