Python AI Engineer

Python AI Engineer London - Hybrid Rate: £600 - £700 Per day - Inside IR35 Start: Mid October Contract - 6 Months

Python AI Engineer required to develop production-grade Python services for Generative AI and complex RAG solutions. You will work across AI workflow orchestration, information retrieval, evidence processing, LLM integration, response generation and validation..This role requires strong production Python experience and practical experience delivering Generative AI and RAG solutions beyond proof of concept.

Job Responsibilities/Objectives:

Design, develop and maintain production-grade Python services for Generative AI and RAG solutions.

Build and integrate LLM workflows using structured outputs, tool calling, schema validation and controlled fallbacks.

Implement vector, lexical and hybrid retrieval, metadata filtering, reranking and evidence selection.

Build asynchronous services with appropriate timeout, retry, cancellation and exception handling.

Develop automated unit, integration, regression and failure-path tests.

Implement structured logging, tracing and operational monitoring.

Monitor and optimise response quality, latency, token usage, cost and performance.

Contribute to technical design, code reviews, engineering standards and production support.

Required Skills/Experience:

Strong commercial experience developing production-grade Python applications and services.

Advanced Python skills, including asynchronous programming, type annotations, modular design and performance optimisation.

Hands-on experience with Pydantic, LangGraph, MS Agent Framework/Semantic Kernel or similar AI orchestration frameworks.

Demonstrable experience delivering Generative AI and RAG solutions beyond proof of concept.

Strong understanding of embeddings, vector search, lexical search, hybrid retrieval, chunking, reranking and evidence selection.

Experience integrating LLMs using structured outputs, tool calling, prompt/model versioning, token management and response validation.

Experience building multi-step, agentic or workflow-based AI applications.

Strong automated testing experience using Pytest or equivalent.

Experience with APIs, distributed services, Git, CI/CD, containers and production observability.

Technical Skillset:

Azure OpenAI, Azure AI Search or equivalent AI and enterprise search platforms.

Pydantic AI, LangGraph, Semantic Kernel or similar orchestration frameworks.

LLM and RAG evaluation approaches, with Azure Foundry or ML Studio preferred.

Docker, Kubernetes, telemetry and load testing.

If you are interested in this opportunity, please apply now with your updated CV in Microsoft Word/PDF format.

Disclaimer Notwithstanding any guidelines given to level of experience sought, we will consider candidates from outside this range if they can demonstrate the necessary competencies. Square One is acting as both an employment agency and an employment business, and is an equal opportunities recruitment business. Square One embraces diversity and will treat everyone equally. Please see our website for our full diversity statement