Senior AI Software Engineer

Senior AI Software Engineer

London (Hybrid, 3 days per week)

Up to £140,000 + Equity

We're partnered with a fast-growing AI start-up building cutting-edge behavioural intelligence technology for the financial services sector. Backed by an exceptional leadership team and industry experts, they're developing a platform that helps organisations better understand client behaviour through advanced AI and large language models.

As their first senior individual contributor engineering hire, you'll play a critical role in shaping both the product and engineering culture from the ground up.

The Opportunity

This is a true 0-to-1 product engineering role. You'll work closely with senior leadership to build and scale a greenfield product, taking ownership across the full stack while driving the architecture and evolution of production-grade AI systems.

You'll have significant influence over technical direction, engineering standards, product decisions and future hiring as the team grows.

What You'll Be Doing

• Building and shipping customer-facing product features end-to-end • Developing and scaling production LLM applications • Owning RAG pipelines and AI application architecture • Implementing guardrails, evaluations, caching and model routing strategies • Working across TypeScript, React, Node.js, PostgreSQL and AWS (Open to different technology backgrounds!) • Building API-first services for enterprise customers • Establishing engineering best practices around testing,…