Job Specifications
About Data At Holland & Barrett
Location: Hybrid working – occasional office presence. London or Nuneaton when required.
Holland & Barrett is investing heavily in the next generation of digital and AI capability - not as an experiment, but as a core part of how we help millions of customers live healthier lives.
We're now hiring our first LLM Data Scientist to shape how LLMs show up across the business - on our website, in our content, in our recommendations, and in the tools our teams use behind the scenes.
The Role
If you're someone who loves the intersection of LLM systems, experimentation, and real‑world product impact, this is the kind of role where your work won't stay hidden. You'll see it live, in customer‑facing journeys, SEO performance, personalisation, and in the quality of the content we publish.
And to be clear: this is not a role for someone who has only ever engineered prompts in isolation. You'll definitely write prompts - but the value here comes from understanding how LLMs behave in real systems, with real data, and knowing how to evaluate, measure, optimise and deploy them at scale. If you have the data science mindset and the LLM engineering skillset, this is where you can genuinely shape things.
What you'll actually be doing?
Designing, testing, and optimising prompts and prompt‑chains for production LLM applications
Building evaluation frameworks to measure quality, safety, relevance, latency and cost
Working with RAG architectures, embeddings and vector databases to improve retrieval and contextual accuracy
Owning and developing our SEO content‑optimisation tool - improving product page copy for both relevance and discoverability
Helping power personalised recommendations and messaging in our Personalisation squad
Enhancing our Wellness Hub (our library of health articles and expert content) by generating, rewriting and improving pieces in safe, evidence‑based ways
Partnering with Data Engineering on context management, memory strategies, tool/function‑calling, observability and logging
Monitoring and mitigating model drift, prompt degradation and system regressions
Acting as a go‑to LLM expert across the business, helping teams understand what's possible and what's not
Staying close to the evolving LLM landscape and translating new ideas into useful, practical improvements
How We'll See Your Impact
Customers engage more with product pages because the content is more helpful and tailored
SEO performance improves thanks to your optimisation tools
We publish higher‑quality health content that's accurate, engaging and aligned with our brand
Customers receive more relevant recommendations at the right moment
Internal teams work faster thanks to stronger, more reliable LLM‑powered tools
Clear evaluation metrics guide smarter, data‑driven AI adoption
LLM capability across H&B grows because you've helped demystify the technology
The Person
What You'll Need
Hands‑on experience developing LLM applications beyond just prompt writing
Solid data science foundations: experimentation, evaluation, statistical thinking, working with real‑world datasets
Strong understanding of: prompt optimisation, RAG, embeddings, vector stores, context management and LLM evaluation
Very strong Python skills - this is a genuinely hands‑on role
Ability to reason about trade‑offs between quality, latency and cost
Experience with Git, version control and CI/CD
Confidence translating complex LLM concepts for non‑technical colleagues
Curiosity, pragmatism, and comfort shaping a first‑of‑its‑kind role
Benefits
Technology Incentive Scheme - we offer different bonus schemes for all grades in Technology, starting at 10%.
Learning and Development opportunity with Holland & Barrett is a great base for career development long term.
Career progression
Pension company contribution
Your wellbeing is paramount so you can get away and take 28 or 33 Days Holiday per year.
Refer and Earn Scheme - as we're growing you can earn money by referring people to join us from your network.
Epic Extras gives you access to exclusive benefits, free advice and savings from a range of retailers and providers.
Stay healthy with Discounted Products - from day one you'll get a 25% discount (on top of other promotions) when you shop at H&B on anything that you buy.
We all need a little help sometimes, so we offer Free 24/7 Confidential Advice & Colleague Welfare.
Mental Health First Aiders - we have lots of qualified Mental Health First Aiders because its all about your health & wellbeing.
We have colleague Reward and Recognition Schemes, so your hard work and loyalty won't go unnoticed.
And many more!
The Company
Holland & Barrett is one of the nation's most loved and trusted brands, known for offering quality health food, vitamins and supplements all sold by highly trained and qualified advisors.
Bucking the current trend of high street retailers, we forecast significant growth and expansion plans in the comin
About the Company
Holland & Barrett is a leading wellness retailer and one of the largest in Europe. We make health and wellness a way of life for everyone, with a leading range of own brand, innovative vitamins, supplements, specialist food, sports nutrition and ethical beauty brands. Established in 1870, Holland & Barrett has been trusted for wellness for over 150 years and has an omnichannel retail presence of more than 1000 stores across 18 countries worldwide, including over 800 in the UK and Ireland**Holland & Barrett’s colleagues are...
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