Applied LLM Specialist

4763532
  • Job type

    Permanent
  • Location

    London
  • Working Pattern

    Full-time
  • Specialism

    Intelligent Automation
  • Industry

    Advertising, Media and PR
  • Pay

    £90,000 - £100,000
  • Closing date

    13 Feb 2026

Applied LLM Specialist

Our client, a market leading agency, is looking for an LLM specialist to design and implement an AI capability within a product environment. The LLM Specialist role is very much a hands-on and delivery-focused role, with an emphasis on reliability, evaluation, and practical integration.

The LLM Specialist responsibilities are
  • Design the approach for integrating LLMs into a product workflow, including model selection and orchestration.
  • Build and iterate prompting strategies, tool use, and structured outputs.
  • Implement evaluation and quality measurement, including test sets, rubrics, and regression checks.
  • Create an improvement loop using real user feedback and outcomes.
  • Add guardrails for safety, reliability, and consistency.
  • Optimise for cost, latency, and throughput using routing, batching, caching, and fallbacks.
  • Work closely with the engineering lead to integrate the AI layer cleanly into the platform.
  • Document configuration, prompts, evaluation methodology, and operating guidelines for handover.
Required experience
  • Proven experience deploying LLM features into real products, not just prototypes.
  • Strong Python and practical ML engineering skills.
  • Experience with several of the following:
    • RAG and embedding
    • Vector databases
    • Fine-tuning or adaptation approaches
    • Evaluation frameworks and measurement
    • Prompt injection considerations and output constraints
  • Strong product mindset and comfort balancing quality, speed, and cost.
Nice to have
  • Experience with workflow tools, internal platforms, or approval and review loops.
  • Familiarity with cloud deployment patterns for AI services.


What you need to do now


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Talk to George Brown, the specialist consultant managing this position

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