Senior Agentic AI Platform Engineer

On; Greater London; Hybrid; GBP 90,000 - 150,000; Full time

Job summary

On is building a dedicated AI & ML Platform team to deliver scalable, observable, and governance-focused agentic AI infrastructure. We seek engineers who can scale pipelines, ship reliable services, and collaborate across product and business teams to embed AI at scale.

You will work on production-grade systems, including evaluation frameworks, routing gateways, and LLM orchestration, while aligning with security and reliability standards across a global brand.

Qualifications

• Strong background in backend, platform, or data engineering with ML/AI platform exposure.
• 3+ years for mid-level, 5+ years for senior, with production-grade agentic AI experience.

Responsibilities

• Architect, scale, and maintain agentic infrastructure and core platform components.
• Partner with business and product teams to accelerate adoption of agentic workflows.
• Contribute to cross-functional strategy for a unified AI/ML ecosystem and ensure secure, observable production systems.
• Establish engineering best practices and evaluate tooling to support safe, scalable AI at scale.

Skills

Backend Engineering

ML Platform experience

AgentOps

Cloud (GCP)

Observability

Communication

Tools

LangSmith

LangFuse

LLM Gateways

Job description

On is building a dedicated AI & ML Platform team to deliver scalable, observable, and governance-focused agentic AI infrastructure. We seek engineers who can scale pipelines, ship reliable services, and collaborate across product and business teams to embed AI at scale.

You will work on production-grade systems, including evaluation frameworks, routing gateways, and LLM orchestration, while aligning with security and reliability standards across a global brand.