Senior Machine Learning Engineer - GenAI, LLM, RAG

Senior Machine Learning Engineer - GenAI, LLM, RAG - 12 month contract

I'm looking for Machine Learning Engineers (and Senior Data Scientists with strong engineering capability) who have real, hands-on experience building GenAI applications end-to-end. Not just prototypes, but production systems.

This is a full-stack ML Engineering role where you'll design, build, deploy, and monitor GenAI applications that integrate LLMs as part of a wider system.

You'll be working on:

  • Building production-grade GenAI applications using Python
  • Developing LLM-powered systems with LangChain, LangSmith, and modern Python libraries
  • Designing and implementing RAG pipelines, vector stores, and retrieval logic
  • Building agentic workflows, tool-calling, and multi-step reasoning systems
  • Implementing guardrails, safety layers, and controls
  • Designing monitoring for latency, drift, hallucinations, cost, and safety signals
  • Integrating LLMs into broader application architectures (APIs, services, orchestration)
  • Working across the full life cycle: data prep - modelling - evaluation - deployment - observability

We're looking for people who have:

  • Delivered real GenAI applications into production, not just PoCs
  • Strong Python engineering skills
  • Experience with LangChain, LangSmith, LlamaIndex, or similar frameworks
  • Deep understanding of LLM behaviour, prompting, evaluation, and optimisation
  • Experience building monitoring, logging, and guardrail frameworks
  • Ability to work across the stack: data, model, application, and infrastructure
  • Strong communication skills and ability to work with product, engineering, and business teams

This is ideal for ML Engineers who love building end-to-end systems, not just models. People who can take a GenAI idea from concept to production and own the full life cycle.

If you've built and shipped GenAI applications and want to work on high-impact, enterprise-scale projects, please apply.

Job Details

Company
Puritas Group
Location
London, United Kingdom
Employment Type
Contract
Salary
GBP Annual
Posted