Head of Data Science

Principle AI Data Scientist (LLM Architecture) A leading UK Managed Service Provider is launching a new applied AI practice for enterprise clients. We're hiring a Principle AI Data Scientist to design LLM solutions, defend the choices behind them, and turn deep model knowledge into results clients will pay for. This is not a back office research role. You'll work directly with client engineering leads and senior technical stakeholders, from the first whiteboard session to production deployment. Why this role stands out

• Real architect-level ownership. You'll shape how LLMs are fine-tuned, evaluated and deployed for named enterprise accounts. You won't be working through someone else's backlog.
• A ground-floor opportunity. You'll help build a new AI practice inside an established, commercially stable business, rather than competing for attention at a crowded AI startup.
• Science that stays sharp. You'll join a small, technically elite team where “customer-facing” doesn't mean watering down the science. It means being trusted to represent it.
• Visible impact. The people making buying and build decisions will see and value your technical depth. What you'll be doing
• Acting as the main technical point of contact for enterprise clients on LLM projects, from scoping through to deployment
• Designing LLM training, fine-tuning and evaluation pipelines for each client's use case and data environment
• Turning unclear client requirements into concrete technical architectures and delivery plans
• Leading technical discovery and whiteboard sessions with client engineering and data science teams
• Owning model performance, evaluation methodology and responsible deployment recommendations
• Working with sales, account management and delivery to make sure every design is technically sound and can be delivered commercially within a managed services model What you'll bring
• 5+ years in applied data science or ML engineering, with hands-on LLM training or fine-tuning experience beyond API use
• Practical experience with transformer architectures, LLM pre-training or fine-tuning workflows, and modern ML frameworks such as PyTorch or Hugging Face
• A strong grounding in evaluation methodology, the trade-offs between RAG and fine-tuning, and production ML deployment patterns
• Confidence and credibility with senior technical stakeholders. You're comfortable with pushback in live technical discussions and equally at home in a boardroom or a terminal. Nice to have
• Experience with distributed training infrastructure (multi-GPU, multi-node)
• A background in pre-sales, solutions architecture or consulting
• Familiarity with model safety, alignment or responsible AI evaluation frameworks
• Experience in an MSP, systems integrator or managed services environment Interested? Location: London Salary: £100,000 - £120,000 Depending On Experience Working pattern: Hybrid