Senior Frontend Engineer - Contract - Outside IR35
Posted Today by SR2 - Socially Responsible Recruitment
£600 Per day
Outside
Remote
London, UK
Summary: The role of Senior Frontend Engineer involves working on a contract basis for an AI product company focused on developing a collaborative platform for creative teams. The engineer will be responsible for scaling and evolving a complex Front End application that integrates real-time collaboration and advanced rendering. This position requires a strong emphasis on engineering quality and performance in a fast-paced startup environment. The role is remote-first with occasional visits to London.
Key Responsibilities:
- Develop and enhance a complex Front End application with real-time collaborative features.
- Implement advanced canvas-based interactions and AI-assisted workflows.
- Manage complex client-side state and ensure performance-sensitive Front End systems.
- Collaborate with a high-caliber engineering team to solve technically challenging browser problems.
- Contribute to the evolution of the product in a fast-moving startup environment.
Key Skills:
- Strong commercial experience with React for building complex Front End applications.
- Experience with real-time web products and interactive applications.
- Understanding of Front End performance optimization techniques.
- Familiarity with advanced client-side state management libraries.
- Ability to work independently and contribute technically from day one.
Salary (Rate): £600 per day
City: London
Country: UK
Working Arrangements: remote
IR35 Status: outside IR35
Seniority Level: Senior
Industry: IT
Senior Frontend Engineer (Contract)
Contract Length: 3-6 months
Rate: £550 - £600 p/d
IR35 Status: Outside IR35
Location: Remote-first with occasional London visits
We're supporting an AI product company building a highly interactive, browser-based collaborative platform used by creative and design-focused teams globally.
They're looking for a Senior Frontend Engineer to help scale and evolve a complex Front End application that combines Real Time collaboration, advanced rendering, multiplayer state management, and AI-powered workflows.
This is not a standard CRUD-style React contract.
The environment is heavily focused on Front End engineering quality, performance, interaction design, and solving technically challenging browser problems.
The RoleYou'll work closely with a small, high-calibre engineering team on a sophisticated web application that includes:
- Real Time collaborative experiences
- Advanced canvas-based interaction
- AI-assisted workflows
- Complex client-side state management
- Rich media and interactive rendering
- Performance-sensitive Front End systems
The product is evolving rapidly, so this role suits someone comfortable operating in fast-moving startup environments where ownership and engineering judgement matter.
Tech Environment- React
- Next.js
- TypeScript
- WebSockets
- State management libraries (Zustand/Redux/MobX)
- WebGL/three.js
- react-three-fiber
What they're looking for
- Strong commercial experience building complex Front End applications in React
- Experience with highly interactive or Real Time web products
- Strong understanding of Front End performance optimisation
- Comfortable working with advanced client-side state management
- Experience working in product-led engineering teams
- Ability to contribute technically from day one with minimal oversight
Particularly interesting backgrounds
- Collaborative tooling
- Design platforms
- Browser-based creative applications
- Data visualisation products
- Real Time SaaS platforms
- Canvas-heavy or rendering-focused applications
Nice to have
- Experience with multiplayer/collaborative systems
- WebGL or 3D rendering exposure
- Experience building performance-sensitive browser applications
- Comfort contributing across the stack where needed
