Founding AI Backend Engineer

Founding AI Backend Engineer

FinTech | UK | Remote-first | £80K-120K + equity

We're hiring a Founding AI Backend Engineer to help shape the technical foundations of an early-stage fintech building AI-native systems in a complex tax and compliance domain.

This role is for someone with a consistent track record of building backend and LLM systems from scratch, who can drive technical direction from day one, not just contribute tickets.

What you'll do:

• Design and build production-grade backend systems for AI-native products
• Build LLM systems end-to-end: agentic workflows, RAG pipelines, eval frameworks
• Design data pipelines for processing unstructured data at scale
• Make architectural decisions that balance speed, reliability, and correctness
• Own core systems from initial design through to production

Tech stack:

• Backend: Python, Go, or Node.js (strong depth in at least one)
• AI/LLMs: Agentic systems, RAG, tool calling, evaluations, LLM orchestration
• Data: APIs, pipelines, structured & unstructured data
• Infra: Cloud-native environments (AWS/GCP/Azure)

What we're looking for:

• Strong backend-first engineering background
• Proven experience building LLM systems in production (not just prompting)
• Experience designing complex systems and making architectural calls
• Comfortable working in ambiguity and driving technical direction
• CS degree not required, but demonstrable systems depth is

If you want to build real AI systems, not demos and help define the technical foundation of a product from day one, this one's worth a conversation. Apply now!