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# AI Engineer

- **Company:** Portfolio Group Ltd
- **Location:** London, UK
- **Experience:** Expert
- **Salary:** £80,000 - £90,000
- **Contract:** Permanent contract
- **Skills:** LangGraph Framework, Artificial Intelligence, Amazon Web Services, Cloud Computing, Python (Programming Language), Machine Learning, Search Technologies, Systems Integration, LangChain, Retrieval-Augmented Generation, Large Language Models, Prompt Engineering, Model Validation, Llamaindex, AI Platforms, Graph RAG, Databricks
- **Published:** November 10, 2026
- **Apply:** https://www.cv-library.co.uk/job/225819836/AI-Engineer

## About the Role

* Strong commercial Python engineering experience.
 * Proven experience designing, building and deploying AI/ML applications in production environments.
 * Excellent understanding of RAG, LLM orchestration, embeddings and vector search.
 * Hands-on experience with LangChain, LangGraph or LlamaIndex.
 * A strong understanding of model evaluation and experimentation, not just prompt engineering.
 * Experience building scalable systems with maintainability, testing and performance in mind.
 * Confidence to own technical decisions, challenge approaches and work collaboratively with senior stakeholders.
 * Experience with GraphRAG, Databricks or customer-facing AI products would be a bonus.

## Description

What happens when RAG isn't retrieving the right information, agents make the wrong decisions or LLM outputs aren't good enough?

We're looking for the engineer who knows how to investigate those problems, challenge the architecture and build something better.

We're partnering with an established organisation making significant investments in AI, intelligent search and generative technology.

This is an opportunity for a Senior AI Engineer to take a leading hands-on role in developing sophisticated AI solutions, with a particular focus on production engineering, retrieval performance, evaluation and scalable architecture.

The challenges you'll tackle

 * Designing and developing production-grade RAG pipelines and intelligent search solutions.
 * Building generative AI and agentic workflows using LangChain, LangGraph and LlamaIndex.
 * Improving retrieval using advanced chunking, reranking, retrieval fusion and grounding strategies.
 * Evaluating LLM outputs, identifying failure patterns and improving accuracy, robustness and reliability.
 * Developing structured evaluation approaches to measure AI quality and guide technical improvements.
 * Exploring model optimisation, fine-tuning and instruction tuning where appropriate.
 * Engineering scalable Python-based AI services and integrating them into wider platforms.
 * Working with cloud infrastructure, with a preference for AWS.
 * Taking technical ownership of solutions, contributing to architecture and mentoring other engineers.