Contract Type: Outside IR35 Day Rate: £375 - £400 per day Senior LLM & Multi-Agent Systems Engineer Location: Flexible (UK or Europe preferred) Type: Permanent / Contract Industry: AI, NLP, and Applied Machine Learning We are seeking a highly experienced AI engineer with deep expertise in large language models (LLMs), multi-agent systems, and emerging prompt and context engineering practices. The ideal candidate will be fluent in the latest industry developments, capable of recalling and applying detailed model specifications, and confident in designing, optimising, and deploying advanced LLM-based architectures for production use. You will work on building scalable, intelligent systems that leverage agentic workflows, advanced reasoning techniques, and multi-agent communication architectures, integrating them into robust, performant, and explainable AI pipelines. Key Responsibilities Architect and implement LLM-based systems with advanced reasoning capabilities, including context engineering, role-based prompting, and multi-agent orchestration. Select and integrate appropriate frameworks and tools (e.g. LangChain, LangGraph, AutoGen, CrewAI, Agno, Smallagons, OpenHands) for specific use cases. Design, optimise, and evaluate tokenisation, embedding, and vector store strategies - including trade-offs between embedding dimensions, indexing performance, and retrieval costs. Implement advanced multi-agent archit...