About the job

Fyxer AI, the fastest growing AI start-up in the UK, is seeking a Staff Product Engineer to join their London team during a period of hypergrowth following a $10M Series A backed by Marc Benioff and 20VC. Since launching in May 2024, Fyxer AI has grown from zero to over $15M ARR with thousands of paying users by building an AI productivity tool that eliminates admin work for client-facing professionals such as consultants, recruiters, and real estate agents. Their platform drafts emails in a user’s voice, takes precise meeting notes, and manages inboxes automatically, enabling people to work smarter and faster. This role offers full ownership of one of Fyxer’s most important products, where you will define success metrics, gather insights directly from customers, create strategy using both data and intuition, and execute by coding and shipping your own solutions. You will also mentor and develop other engineers, set technical direction, and ensure reliability by monitoring logs, analyzing support tickets, and resolving issues. The ideal candidate has startup or founder experience, expert-level knowledge of TypeScript and serverless architecture, and thrives as a fullstack engineer capable of working across frontend, backend, and data using SQL. You should be passionate about product ownership, eager to contribute to roadmap decisions, and highly motivated by the potential of AI. Fyxer AI values autonomy, creativity, and small high-talent teams that prioritize shipping meaningful features over headcount growth. Their stack includes TypeScript, React, Firebase, Firestore, Cloud Functions, PubSub, Cloud Storage, TailwindCSS, React Query, Posthog, BigQuery, Metabase, Sentry, and GitHub Actions. In return, they offer up to £200K base salary plus equity, private medical and dental insurance, pension, 25 days annual leave, and visa sponsorship for exceptional candidates. This role is on-site four days a week in their Chancery Lane office in London, providing a rare opportunity to shape the future of one of the UK’s most promising AI companies alongside a world-class team.