Principal Engineer (backed by Y Combinator, $5M+ ARR, $23M+ raised)

The role

A principal-level engineer will own entire problem spaces and technical domains within an event-driven TypeScript platform. You will manage systems including the factory spine, clinical work spine, agent operations, and the data estate.

What you will do

• Own the factory spine to increase deployment volume towards 10,000 PRs a month
• Manage the clinical work spine for orders, tasks, commands, and receipts
• Own agent operations in production including LLM agents with tool use
• Manage the data and metrics estate including warehouse and analytics platform
• Perform architecture syncs and make calls within your domain

Required qualifications

• Owned architecture across multiple companies or many codebases
• Staff-plus IC, chief-architect, or platform-consulting background
• Ship daily at high volume with a fleet of AI agents
• Ability to take ambiguous, load-bearing problems and build them end to end
• Proactive written communication
• Hold clinical-grade correctness including auditability, HIPAA, and fail-closed defaults

Benefits

• Medical, dental, and vision benefits
• In-person retreats
• Meal stipends
• Flexible, unlimited vacation policy

Before you apply

• US Visa Sponsorship: Yes

About the company

Legion Health is building autonomous medical care using AI infrastructure, starting with psychiatry. The company is backed by Y Combinator and leading venture capital firms.