Hays Technology
Senior LLM Engineer (RAG & AI Applications)
Job Description
Salary: £85,000 - 125,000 per year
Requirements:- We require a Masters or PhD degree in a STEM or Computing discipline.
- We require full-time, onsite work 5 days a week in our Guildford office.
- We require deep experience in LLM development and deployment.
- We require senior-level experience in AI/ML roles.
- We require 3+ years of hands-on experience designing, building, and deploying LLM-based applications into production environments.
- We require proven experience with C++/C#, ideally integrating ML features into C++ applications.
- We require experience with at least one high-level scientific language such as Python or Julia.
- We require strong technical leadership skills and a commitment to driving engineering best practices and standards.
- We ideally want a background in scientific computing, time-series data, or complex data environments.
- We design, build, and deploy LLM-based applications into production environments.
- We bridge the gap between advanced AI/ML and production-grade software.
- We take models from concept through to scalable deployment.
- We help instil best practice within a newly formed team in our R&D department.
- We influence how AI capability is embedded into our product suite.
- We balance greenfield innovation with enhancement of existing platforms.
- We work across structured, unstructured, and streaming data.
- We contribute to modern AI approaches and help shape how data drives product capability.
- We drive engineering best practices and standards.
- AI
- C#
- Embedded
- Julia
- LLM
- Machine Learning
- Python
- Cloud
- RAG
More:
We are a fast-growth, highly respected software engineering business applying advanced modelling, data science, and machine learning to solve complex, real-world problems at scale. Our technology underpins critical decision-making in high-value environments, combining deep domain expertise with modern engineering practices. We have a strong track record of success and a growing international footprint, and we are investing heavily in AI as a core pillar of our future. This is a fully onsite role based in our head office in the heart of Guildford, close to the University and with excellent transport links to London and the surrounding areas in Surrey. We offer an excellent rewards scheme including an annual bonus of up to 25%, 10% pension match, private healthcare, 25 days holiday, long term sick cover, on-site parking, a shuttle bus for train commuters, and a modern office space with excellent amenities. There are also leadership opportunities as we continue to grow our engineering team.
last updated 32 week of 2026
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About Hays Technology
Hays Technology
Guildford
IT
Skills & Technologies
Inferred from job description
Salary Insight
£105,000
This role
£75,000
UK median
This salary is 40% above the UK median for Senior roles (£75,000/yr).
Based on 2024–2025 UK technology sector benchmarks