Senior AI/ML Engineer — Agentic LLM Systems (Hybrid, London)

Experis UK; Greater London; On-site; GBP 101,000 - 129,000; Full time

Job summary

Experis UK is hiring an AI / Machine Learning Engineer to design, build, and scale agentic LLM systems for enterprise environments. The role involves crafting tool-calling frameworks, multi-step planning, and robust back‑end services that support AI-driven workflows.

You will work with researchers and engineers to diagnose failures, optimize latency and cost, and contribute to observability and monitoring of production AI systems.

Qualifications

• 4+ years’ experience in ML/AI engineering (LLMs, recommender systems, optimisation, or similar).
• Proven hands-on experience building LLM agents, RAG systems, or orchestrated AI workflows in production.
• Strong Python (with PyTorch, TensorFlow, or similar frameworks).
• Experience with agent frameworks (LangChain, LangGraph, AutoGen, or similar).
• APIs, backend services, and microservices architectures.
• Cloud platforms (AWS, GCP, or Azure) and containerised systems (Docker, Kubernetes).
• Event-driven or serverless architectures familiarity.
• CI/CD pipelines, testing, and infrastructure as code.
• Debugging complex, distributed AI/ML systems.
• Experience running large-scale experiments and evaluating latency, accuracy, cost.
• Observability tools for production systems.

Responsibilities

• Design and build tools, workflows, and infrastructure for agentic LLM systems.
• Develop RAG pipelines, embeddings workflows, and retrieval systems for enterprise data.
• Diagnose and fix failures in agent-generated code and workflows.
• Build frameworks for tool-calling, multi-step planning, orchestration, and agent routing.
• Integrate with LLM providers and support multi-model usage.
• Develop backend services and APIs to support AI-driven applications and workflows.
• Build and run experiments to improve reliability, latency, cost, and success rates.
• Contribute to evaluation frameworks, observability, and monitoring of LLM/agent performance.

Skills

Python

PyTorch

TensorFlow

LangChain

LangGraph

Docker

Kubernetes

AWS

GCP

Azure

APIs

Microservices

CI/CD

Observability

Tools

Pinecone

Weaviate

OpenSearch

Job description

Experis UK is hiring an AI / Machine Learning Engineer to design, build, and scale agentic LLM systems for enterprise environments. The role involves crafting tool-calling frameworks, multi-step planning, and robust back‑end services that support AI-driven workflows.

You will work with researchers and engineers to diagnose failures, optimize latency and cost, and contribute to observability and monitoring of production AI systems.