Senior AI Engineer: Production RAG & Agentic Systems

Harrington Starr; England; On-site; GBP 90,000 - 130,000; Full time

Job summary

Harrington Starr partnering with a leading investment firm to hire a Senior AI Engineer who will own the end-to-end lifecycle of production AI systems, from idea to deployment. You will work on RAG pipelines, agentic AI, and LLM applications, building scalable Python APIs and backend services.

This hands-on role offers ownership, experimentation, and shaping how AI is built and used across the business, with emphasis on reliability, observability, and robust testing.

Qualifications

• Strong Python/software engineering background.
• Experience taking AI/LLM systems into production.
• Hands-on experience with RAG and agentic AI.
• Experience with LangGraph, LangChain, LlamaIndex, AutoGen or similar.
• Entrepreneurial mindset and ownership.

Responsibilities

• Build and own production-grade RAG pipelines.
• Design agentic and multi-agent systems with tool use and memory.
• Develop Python APIs and backend services.
• Deploy and monitor LLM-powered applications across environments.
• Improve reliability with evals, guardrails, observability, and testing.

Skills

Python software engineering

Production AI systems

RAG

agentic AI

LangGraph

LangChain

LlamaIndex

AutoGen

Tools

OpenAI APIs

Anthropic models

Job description

Harrington Starr partnering with a leading investment firm to hire a Senior AI Engineer who will own the end-to-end lifecycle of production AI systems, from idea to deployment. You will work on RAG pipelines, agentic AI, and LLM applications, building scalable Python APIs and backend services.

This hands-on role offers ownership, experimentation, and shaping how AI is built and used across the business, with emphasis on reliability, observability, and robust testing.