Senior Machine Learning Systems Engineer

Senior Machine Learning Systems Engineer

London, United Kingdom | Posted on 02/12/2026

We are building the next generation of intelligence. This isn’t just about calling an API; it’s about engineering the plumbing, the memory, and the reasoning logic that allows AI to navigate complex datasets. You will be responsible for delivering fast, brilliant, and architecturally sound solutions.

• Cognitive Architecture: Beyond simple prompts, you will engineer the decision‑making loops (agents) that allow our tools to self‑correct and execute multi‑step coding tasks.
• Context Engineering: Develop the retrieval and embedding logic that ensures the model “sees” the right data at the right time, minimizing noise and maximizing signal.
• System Integrity: Move beyond “vibe‑based” testing. You’ll build rigorous, automated frameworks to quantify model behaviour and prevent regressions in production.
• Model Lifecycle: Own the decision between fine‑tuning a specialised small model versus orchestrating a frontier LLM, balancing latency with reasoning depth.
• Technical Leadership: Act as the “Engineer’s Engineer,” setting the standard for how we write production‑grade ML code and mentor the team on high‑stakes delivery.

• The GenAI Stack: Extensive experience with the “Agentic” ecosystem (orchestration frameworks, vector‑native databases, and semantic search).
• Production ML: A history of shipping models that actually handle traffic. You know that “done” means deployed, monitored, and stable.
• Code‑Fluent: You are a strong software engineer. You are as comfortable in the depths of a Python backend as you are tweaking a model’s temperature. Familiarity with JVM‑based languages (Java/Kotlin) is a significant edge.
• The Scientific Method: You don’t guess; you experiment. You have a background in statistical validation and know how to prove a model’s value via data.

• You find the “unknowns” of Agentic AI exciting, not paralyzing.
• You believe that a model is only as good as the data pipeline feeding it.
• You are tired of “wrapper” apps and want to build deep, integrated AI systems.
• You have 5+ years of total ML experience, with a heavy recent focus on the LLM frontier.