Lead Fullstack Engineer

Lead Full-Stack Engineer

£50,000-£75,000 plus bonus and benefits

St Ives, Cornwall

We're working with a founder-led HR technology business to find a Lead Full-Stack Engineer to join them at a pivotal moment in their growth. Their AI-powered SAAS platform is already in the hands of design partners, has clear commercial traction, and is positioned to become the category leader in a space that is moving fast.

You'll be the technical lead on the platform build, working directly with the founder to ship features that reach board-level buyers at some of the UK's leading businesses. As Lead Full-Stack Engineer, you'll have real ownership over architecture decisions and a genuine voice in what gets built next.

Responsibilities as a Lead Full-Stack Engineer:

  • Build and maintain the platform in Next.js, owning frontend delivery end to end
  • Deploy and manage infrastructure on Vercel with Cloudflare for edge networking and performance
  • Work with Supabase and PostgreSQL-backed data layers to support core product logic and reporting
  • Integrate LLM APIs and AI gateway tooling to power intelligent scoring, generation and insight outputs
  • Implement and maintain auth flows using Clerk or equivalent modern auth platforms
  • Contribute to headless CMS architecture and custom content tooling
  • Shape architecture decisions as the platform scales, including the move toward a serverless, API-first approach
  • Have a genuine voice in what gets prioritised, this is a small team and your input matters

Lead Full-Stack Engineer Requirements:

  • Solid Next.js experience and comfortable owning a frontend codebase in a serverless, no-backend environment
  • Hands-on experience with Vercel, Supabase or comparable modern deployment and BaaS platforms
  • Proven experience integrating LLM APIs and AI gateway tooling (OpenAI, Anthropic, Gemini or similar) into production applications
  • Strong JavaScript or TypeScript fundamentals
  • Experience with auth platforms such as Clerk, Auth0 or similar
  • Familiarity with Cloudflare and edge networking principles
  • Comfortable in an early-stage environment where you'll wear more than one hat
  • An interest in AI literacy, workforce capability or assessment products is a genuine plus

Why apply as a Lead Full-Stack Engineer?:

  • Build something from the ground up with real commercial traction already behind it
  • Work directly with the founder with meaningful input into product direction
  • Premium AI tooling from day one, this is an AI-native build
  • Hands-on experience with a modern stack across Vercel, Supabase, Cloudflare and LLM APIs
  • Hybrid working with flexibility built in
  • Real scope to grow as the platform scales from design partners to enterprise

If you're a Lead Full-Stack Engineer who wants early-stage ownership on a product with genuine market timing behind it, get in touch now.

Due to the high volume of applications, not all applicants will receive feedback.

Job Details

Company
Formula
Location
St Ives, England, United Kingdom
Hybrid / Remote Options
Posted