Senior LLM Engineer (RAG & AI Applications)

Senior LLM Engineer (RAG & AI Applications)
Guildford, Surrey (Fully Onsite)
£75000 - £125,000 + 25% Bonus, 10% Pension, Private Medical.

- Must have a Masters or PhD Degree in a STEM/Computing discipline.
- Must work full-time, 5 days a week in the Guildford office.
- Must have deep experience in LLM development and deployment.

Your new company
You'll be joining a fast-growth, highly respected software engineering business that applies advanced modelling, data science, and machine learning to solve complex, real-world problems at scale.

Their technology underpins critical decision-making in high-value environments, combining deep domain expertise with modern engineering practices. With a strong track record of success and a growing international footprint, the company is investing heavily in AI as a core pillar of its future.

You will be working full-time in their head office location in the heart of Guildford close to the University and with excellent transport to London and the surrounding areas in Surrey.

Your new role
The key to this role is hands-on experience designing, building, and deploying LLM-based applications into production environments.

We're looking for a Senior Engineer who can bridge the gap between advanced AI/ML and production-grade software, taking models from concept through to scalable deployment. It is not purely an AI/ML role, nor is it a pure coding role - it sits in between the two disciplines as part of a newly formed team within an R&D department helping to instil best practice.

You'll have the opportunity to influence how AI capability is embedded into a well-established product suite, balancing greenfield innovation with enhancing existing platforms. Working across structured, unstructured and streaming data, you'll contribute to modern AI approaches and help shape how data drives product capability.

It's a well-established business with decades of experience taking them a market leading position. Building on an impressive 2024 they pushed towards 100 headcount and have the investment and product positioning to double this in the coming 12 months, with a particular focus on the Engineering team. Given this imminent growth there are leadership opportunities to aspire to down the line.

It's genuinely challenging applied AI in a complex domain. If you're motivated by seeing your work have tangible impact in production, this is an opportunity to operate at a level most roles don't offer.

What you'll need to succeed
This role requires existing Senior level experience in AI/ML roles, 3+ years working hands-on experience designing, building, and deploying LLM-based applications into production environments, not just experimentation.

You must have proven experience working with C++/C# (ideally integrating ML features into C++ applications), and at least one high-level scientific language (e.g., Python, Julia) working at the interface of research and software development.

You will possess strong technical leadership skills and will be motivated to drive engineering best practices and standards.

You must have an advanced Degree in a STEM/Computing discipline and ideally a background in scientific computing, time-series data, or complex data environments.

What you'll get in return
You'll work for a technology focused company building innovative products. There's an excellent rewards scheme in place including an annual bonus up to 25%, 10% pension match, private healthcare, 25 days holiday and long term sick cover. There is parking on site or a shuttle bus for train commuters to Guildford and a modern office space with excellent amenities.

What you need to do now
To find out more and to be considered for this position please apply directly, or contact Max Wilcock, Senior Business Director on (phone number removed).

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