We're looking for a Principal/Staff Software Engineer to build and own the autonomous AI agent systems behind an early-stage healthcare AI startup, starting from scratch. You'll design and ship agent harnesses, tool calling, MCP integrations and multi-turn routing infrastructure for agents that carry out full clinical tasks in large healthcare settings. This is a hands-on individual contributor role. The Staff/Principal title reflects the maturity and ownership expected, not people management. The company wants builders and problem solvers with real intellectual horsepower, people who like hard, open-ended problems and want to own them end to end. You'll work in Python and modern systems languages, on distributed systems that have to be reliable, auditable and safe in a clinical context. It's a rare chance to shape the core technical foundations of a 01 product alongside a very strong engineering team.
Details: Schedule: Full time Location: Remote (Europe) Start: ASAP Duration: Long-term English: Fluent Type of collaboration: B2B Contract or Internal Employment (via EOR in any EU country)
About the project: The project is a stealth, well-funded healthcare AI startup at the pre-seed, 01 stage. It is building autonomous agents that take on full doctor tasks in large healthcare settings. The founders are experienced engineering and healthtech leaders with two healthtech unicorns on their track record. Trials with healthcare partners are already running, and more are on the way. The engineering team has 11 people and is growing, with backgrounds from companies like Google Zurich and NVIDIA and universities like Oxford and TUM. The culture is built around strong IC engineers with good principles who move fast, own their systems and ship to real users.
You have:
Current or recent role as Principal, Staff or Senior Engineer (ML/AI, Software, Backend or Platform)
Proven 01 engineering experience: you've built a product or platform from scratch
Hands-on experience building AI agents, tool calling or multi-turn routing systems and shipping them to production
Strong Python skills and experience with distributed systems at scale
A track record at top tech companies, leading AI labs or well-known AI-native startups that run AI at scale
Recent hands-on coding, not only architecture or management
A stable career history with meaningful tenures
Based in Europe
Nice to have: a degree in Math, Physics or Computer Science from a top university (e.g., Oxford, Cambridge, TUM)
Nice to have: advanced agent-infrastructure experience (custom agent harnesses, MCP, routing, prompt management)
Nice to have: a Data Science or Machine Learning background
Nice to have: experience with Rust, Go or TypeScript
Nice to have: healthcare domain experience, including compliance (e.g., HIPAA/GDPR) or audit trails for ML systems
What to do:
Design, build and own autonomous AI agent systems from scratch, end to end
Build agent harnesses, tool-calling layers and MCP integrations that work reliably at scale
Develop multi-turn routing and orchestration infrastructure for complex clinical workflows
Architect the distributed backend and infrastructure for agents running in large healthcare environments
Build auditability, safety and evaluation into agent systems so they fit a clinical setting
Turn product needs into working systems quickly and help shape the product with the founders
Raise the engineering bar through code quality, sound principles and pragmatic technical decisions
Interview process: 1. HR screening 2. Founder intro call 3. Coding session in python (can use AI during the coding session) 4. 1h agentic system building 5. 1h infrastructure 6. 1h product thinking 7. Offer
