Founding Product Engineer

This is a role that TechTree is recruiting for on behalf of one of our clients. TechTree is an AI-driven recruitment platform working with high-growth companies. When you apply, our AI Agent matches you not just to this role, but to other relevant opportunities across our network, so one application can unlock multiple roles. Founding Product Engineer — Own the full product surface at a seed-stage AI security company backed by EF and Sequoia Scout. King’s Cross, London, on-site. A seed-stage AI security company has grown to seven-figure revenue within months of launch, on multi-year contracts with leading enterprises in financial services, regulated technology, and healthcare. Founders from Palantir, Oxford, Stanford, and ETH. Backed by UK and US institutional investors and angels from Meta, Isomorphic Labs, Palantir, and SpaceX. They’re building agent-native risk infrastructure — risk management and trust-building, delivered by AI agents, run continuously rather than at fixed checkpoints. Hundreds of billions of dollars flow through these functions today. They’re going to move to agent-native platforms in the next five years. This is not a UI cleanup role. You own the entire product surface — UI, API, and the agent-powered features in between. The bar isn’t that the code is clean, but that you built the right thing, customers feel it, and it shipped while the problem was still worth solving. What You’ll Own → Ship customer-facing product end to end — frontend, backend, and the agent-powered features in between → Own features from “is this even worth building?” through design, build, and the messy reality of customers using them → Work close to customers and FDEs, and turn what you hear straight into shipped product → Move fast with Claude Code and AI tooling, without shipping anything you’d be embarrassed to take into a security review → Bring product and design taste — you care how it feels, not just whether it compiles What We’re Looking For → 6+ years shipping production software across the stack in a small, fast-moving team — TypeScript ideally → A track record you can point to: things you decided on, built, and watched customers actually use → Genuine product instinct — you can tell the difference between impressive and useful, and optimise for useful → Front-to-back range: a React UI a customer enjoys, and the API and data model that make it real → AI-native working style — Claude Code is already in your daily loop → High agency — you see the gap, you close it, you don’t wait to be told → Based in London, on-site at King’s Cross Nice to have: LLM features in production, B2B SaaS / GRC / security domain experience, early-stage or founding-team background, real design chops Stack: TypeScript, Node.js, React, Tailwind, Express, Azure, Postgres, Docker, GitHub Actions, Terraform. Anthropic-first AI. Claude Code throughout. Compensation: Top decile London market + meaningful EMI-eligible equity What is TechTree? TechTree combines AI agents with a human support team to give candidates a better, more transparent hiring experience. Our AI Agent gets to know your background, experience, and what you’re optimising for. It continuously matches you to live roles across our network where there’s genuine alignment, not just keyword overlap. Our Human Team is there to support you through the process — answering questions, adding context, and making sure you’re never left guessing or ghosted. We only post real jobs. Every role on TechTree is a live, active hire.