Senior Full-Stack Software Engineer in London

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Job Description

Senior Full-Stack Software Engineer

London (Victoria) · 3 days in office · £100,000 – £120,000 · Permanent

Our client is a newly launched, VC-backed tech business operating in a highly traditional professional services sector. Founded by repeat founders with a track record of building and scaling high-growth, category-leading consumer businesses, they are using AI and automation to fundamentally reimagine how services in their space are delivered.

The opportunity

This is a rare greenfield engineering role at a genuinely early-stage business. The successful candidate will join a small, senior founding team and take real ownership of the technical foundation from day one — building the stack, setting the architecture, and establishing the patterns that everything else will be built upon.

The role spans customer-facing product, backend automation, AI agent orchestration and internal tooling — with significant scope to grow as the business scales.

What you'll be doing

• Building the customer-facing platform from the ground up — timelines, task-based views and embedded AI assistance
• Owning backend automation workflows, AI agent orchestration and data pipelines
• Building internal tooling to support the team in reviewing and approving AI-generated work
• Setting engineering patterns and architecture that future hires will build on

What they are looking for

• 5+ years building modern web applications with a strong backend emphasis
• Strong command of React/Next.js and Python/TypeScript
• Experience with AI agent orchestration frameworks (e.g. LangGraph, OpenAI Agent SDK)
• The architectural judgment to make confident decisions on a fast-moving, greenfield stack
• A background in high-growth, VC-backed startups — you thrive in fast, dynamic environments
• London-based with existing right to work in the UK (visa sponsorship not available)

Why this role

• A true ground-floor opportunity at a well-funded, early-stage business disrupting a traditional sector
• Founding team with a proven track record — previously built one of the UK's fastest growing consumer brands
• Backed by respected VC funds with a recent funding round closed
• Real ownership and influence over product and architecture from day one
• Work at the cutting edge of AI and automation in a sector ripe for disruption

If this role sounds of interest, please apply now!

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