Senior Full Stack Engineer

Senior Full Stack Engineer (Contract) - Remote - £600 per day

We’re hiring a Senior Full Stack Engineer to join a team building a greenfield, AI-powered productivity platform designed to help teams automate workflows, surface contextual insights, and unlock internal knowledge using large language models.

This is a hands-on engineering role where you’ll work across the full stack, shaping both product and architecture in a fast-moving, product-led environment.

What you’ll be doing

You will take ownership of building and scaling a modern full-stack application, including:

• Developing and maintaining a full-stack web platform using Next.js (React) on the frontend and Node.js (Express) on the backend
• Integrating Claude AI (Anthropic API) to deliver features such as document summarisation, semantic search, and conversational assistants
• Designing and building RESTful and GraphQL APIs to support real-time, dynamic user experiences
• Creating responsive, accessible UI components using modern React patterns (hooks, context, server components)
• Implementing secure authentication and authorisation using JWT and OAuth, including role-based access control
• Optimising application performance, improving page load times through code-splitting, caching, and backend tuning
• Building scalable data pipelines and prompt orchestration layers to improve AI response quality and reduce token usage
• Collaborating closely with product, design, and data teams in an agile delivery environment
• Owning CI/CD pipelines and cloud infrastructure across AWS and Vercel

Tech Stack

• Frontend: React, Next.js, TypeScript
• Backend: Node.js, Express
• APIs: REST, GraphQL
• Data: PostgreSQL, Redis
• Cloud/Infra: AWS (Lambda, S3), Vercel, Docker
• AI: Claude (Anthropic API)
• Auth: JWT, OAuth

What we’re looking for

• Strong experience building production-grade full-stack applications
• Solid knowledge of React/Next.js and Node.js ecosystems
• Experience working with APIs (REST and/or GraphQL)
• Familiarity with cloud platforms (AWS preferred) and modern deployment practices
• Exposure to AI/LLM integrations is highly desirable
• A pragmatic engineer who can move between frontend, backend, and infrastructure