Full job description

Senior Product EngineerLondon (Hybrid) | Up to £140,000 + EquityLooking to make a genuine impact at an early-stage AI startup? This is an opportunity to join a well-funded business as one of its first engineering hires, taking ownership of a product already being tested by major enterprise customers.The CompanyThis AI startup is building a behavioural intelligence platform that helps financial services organisations better understand customer behaviour and decision-making. Backed by significant early-stage investment, they are working with large enterprise clients and moving from proof-of-concept projects towards commercial deployment. With a small, highly capable team, they are focused on building scalable AI products with real-world impact.The RoleYou will take ownership of product development, helping to build and scale an AI-powered platform from an early stage.Responsibilities include:*Building LLM-enabled products and features used by enterprise customers
*Designing and developing backend services, APIs, and platform capabilities
*Owning RAG workflows and AI application architecture
*Managing evaluation frameworks, testing, monitoring, and quality standards
*Optimising LLM performance, scalability, and cost efficiency
*Working closely with product leadership and customers to shape the roadmap
*Establishing engineering best practices across development and deployment
Your Skills & Experience*Strong experience as a Product Software Engineer
*Proven track record building and shipping an LLM-based product from 0 to 1
*Experience owning architecture, product decisions, and implementation
*Strong backend engineering experience with API-first products
*Hands-on experience with RAG and production AI systems
*Understanding of token usage, model evaluation, and cost optimisation
*Ability to operate autonomously in a startup environment
*Strong communication and stakeholder management skills
Desirable:*Experience with Node.js, TypeScript, and React
*Computer Science background
*Experience within AI startups, technology companies, or financial services
What They Offer*Salary up to £140,000
*Meaningful equity package
*Hybrid working in London
*Significant ownership and autonomy
*Opportunity to shape the engineering culture and technical direction
*Direct exposure to founders and business leadership
How to ApplyApply today to learn more about this opportunity to build and scale cutting-edge AI products within a fast-growing startup.