Senior / Lead Applied AI Engineer- AI Labs

Sits within On's AI Lab and Emerging Technology Incubation team, which explores, prototypes, and builds frontier digital products and agentic systems intended to help everyday people build a joyful, lifelong relationship with movement while transforming organisational operations. The Lead Software Engineer serves as a core technical anchor across backend, data, and applied-AI architectures, blending early-stage product exploration with the engineering rigour needed to deploy scalable, production-ready systems. The position reports to the Senior Lead - Staff Software Engineer for AI Labs and works closely with Product, Design, and Research.

• Lead backend, data, and applied-AI architecture across emerging incubation ventures, contributing across frontend and mobile surfaces to ship cohesive vertical slices.
• Partner with Product, Design, and Research to translate early-stage hypotheses into structured domain models, clear technical RFCs, and production-ready applications.
• Design and build core infrastructure for interactive, multimodal agentic experiences, including low-latency streaming runtimes, tiered agent memory structures, hybrid retrieval pipelines, and programmatic evaluation frameworks.
• Validate user value at early-stage speed while establishing cloud-native (GCP, GKE), secure, observable foundations that transition smoothly into platforms across wider engineering clusters.
• Leverage frontier AI tooling and coding agents to explore unfamiliar domains rapidly, pairing velocity with strict type safety, deep system comprehension, and maintainable code that elevates engineering standards across the squad.
• Serve as a collaborative technical partner across teams in Zurich, prototyping partners in London, and cross-functional stakeholders, shaping strategic product direction and technical execution.

• Proven experience building production-grade multimodal agentic systems, including components such as tiered agent memory, multimodal ingestion, RAG, real-time voice or streaming pipelines, tool integration protocols (such as MCP), and automated evaluation workflows.
• A degree in Computer Science, Software Engineering, or a related technical discipline, or equivalent practical experience.
• Demonstrated track record operating in high-ambiguity environments with a strong product mindset.
• Experience navigating enterprise cloud infrastructure (GCP, GKE) and aligning stakeholders through architectural RFCs.
• Strong engineering foundations in Python (FastAPI, Pydantic, asyncio) and/or TypeScript (NestJS).
• Depth in relational and vector data modelling (PostgreSQL, pgvector), event-driven architectures, and API design.
• Practical background in building and scaling distributed backend systems.
• Adaptability to support frontend/mobile applications (React, TypeScript, Flutter) or container infrastructure (Docker, Kubernetes) when initiatives require it.
• A collaborative mindset skilled at partnering with Product, Design, and Research to shape early concepts into reliable software solutions.
• A self-directed learner driven to explore emerging technical domains and tackle complex, evolving problems.

• Familiarity with real-time multimodal streaming runtimes (such as LiveKit, WebRTC, Gemini Multimodal Live, OpenAI Realtime, or ElevenLabs) and low-latency interaction patterns (barge-in handling, prefetching, asynchronous tool dispatching).
• Experience collaborating with external technology partners or working within health, human movement, or advanced R&D incubation settings.

• Hybrid role working 3 days a week in the Zurich office.

• Relocation support is available for this role.

operates like a research laboratory, bringing together engineering, sport science and design experts to challenge limits and create solutions that shape the future of On and the industry.