LLM / GenAI Engineer

Duration: Initial 6 months (with strong extension potential)

About the Role

We're supporting a leading organisation looking to hire an experienced LLM / Generative AI Engineer to design and deliver advanced GenAI solutions.This is a hands-on contract role suited to someone with deep expertise in Large Language Models (LLMs), prompt engineering, and building production-grade GenAI applications. You'll play a key role in delivering innovative AI capabilities that drive real business value.

Key Responsibilities

• Design, build, and deploy LLM-powered applications and GenAI solutions
• Develop and optimise prompt engineering strategies for performance and accuracy
• Implement RAG (Retrieval-Augmented Generation) pipelines using structured and unstructured data
• Fine-tune and customise foundation models and LLMs where required.
• Integrate GenAI solutions into enterprise systems, APIs, and applications
• Work with data teams to build and optimise vector databases and embedding pipelines
• Ensure solutions are scalable, secure, and production-ready
• Implement monitoring, evaluation, and guardrails for LLM outputs
• Collaborate with stakeholders to translate use cases into technical solutions
• Stay up to date with emerging trends in LLMs, GenAI, and AI tooling

Experience Required

• Strong commercial experience (typically 4-8+ years) in software engineering, data science, or machine learning
• Proven experience building and deploying LLM / Generative AI applications in production environments
• Hands-on experience with RAG architectures, embeddings, and vector search
• Experience working with LLM APIs and frameworks (e.g., OpenAI, Azure OpenAI, Anthropic, Hugging Face)
• Strong understanding of prompt engineering techniques and optimisation strategies
• Experience working with vector databases (e.g., Pinecone, Weaviate, FAISS, Chroma)
• Practical experience with model evaluation, tuning, and performance optimisation
• Experience integrating AI solutions into APIs, microservices, and front-end applications
• Strong understanding of data handling, preprocessing, and pipeline development
• Knowledge of AI safety, hallucination mitigation, and guardrail implementation
• Experience working in agile, cross-functional delivery environments
• Previous contract or consulting experience in enterprise settings is highly desirable.

Key Skills

• Python (essential)
• LLM frameworks (LangChain, LlamaIndex, Semantic Kernel)
• API integration and microservices development
• Cloud platforms (Azure, AWS, or GCP)
• Vector databases and embeddings
• Git, CI/CD, and DevOps practices

Desirable Experience

• Experience with Azure AI / Microsoft Copilot stack
• Fine-tuning open-source models (e.g., LLaMA, Mistral)
• Experience with multi-modal models (text, image, audio)
• Front-end integration experience (e.g., React-based AI applications)
• Exposure to AI governance and responsible AI frameworks
• Industry experience in [Finance / Retail / Healthcare - tailor as needed]

What's on Offer

• Opportunity to work on cutting-edge GenAI and LLM projects
• High-impact role delivering real-world AI use cases
• Flexible working arrangements
• Competitive day rate with strong extension potential

Apply Now

If you're a skilled LLM / Generative AI Engineer looking for your next contract and want to work on innovative AI solutions, we'd love to hear from you.

Hays Specialist Recruitment Limited acts as an employment agency for permanent recruitment and employment business for the supply of temporary workers. By applying for this job you accept the T&C's, Privacy Policy and Disclaimers which can be found at hays.co.uk