Senior React Native / Expo Engineer

What You'll Do

• Architect the Mobile Clinical Experience: Build dynamic, high-performance mobile tools for patients and providers. Integrate deeply with Apple HealthKit and Google Health Connect to ingest and visualize real-time patient data. Build responsive, secure messaging systems connecting patients to care teams.
• Leverage the Expo Ecosystem: Manage EAS builds, configure custom native modules via Config Plugins, and push seamless over-the-air (OTA) updates to iterate rapidly.
• Design for the Edge: Architect robust offline-first data synchronization strategies and implement aggressive local caching to handle spotty connections.
• Champion the Mobile UX: Obsess over premium native feel, frame rates, navigation transitions, keyboard avoidance, and accessibility standards.
• Build Agentic Workflows: Integrate frontier agentic AI models into mobile interfaces to automate clinical operations and patient support. Use AI tools to accelerate your own development.
• Raise the Engineering Bar: Own mobile architectural decisions, establish code reuse patterns between web and mobile, perform rigorous code reviews, and improve mobile testing practices.

Who You Are (Requirements)

• 5-7+ years of frontend engineering experience with deep, specialized focus on React Native and Expo. Built, shipped, and maintained complex, data-heavy mobile applications in production.
• Expo and Mobile Infrastructure expert: Manage EAS builds, integrate complex native modules (HealthKit/Health Connect) without ejecting, navigate iOS App Store and Google Play review guidelines.
• Master mobile state and performance: Understand React render cycle on mobile, prevent UI thread blocking, optimize list rendering for large datasets, orchestrate complex async data fetching securely.
• Full lifecycle owner: Manage CI/CD pipelines, monitor crash rates (e.g. Sentry), own app reliability in production.
• AI-altered workflows: Use frontier agentic tools (e.g. Codex, Claude) to build faster; able to audit and verify AI output.
• Collaborative builder with low ego, high standards, excellent communication. Thrive in cross-functional healthcare environments shaped by regulations, compliance, and patient safety.
• Excited to work 5 days/week onsite in San Francisco office.

For Staff leveling: Demonstrated track record of setting technical direction across teams, navigating ambiguity, and leveling up engineers.

Nice-to-haves: Experience with native iOS (Swift/Objective-C) or Android (Kotlin/Java).

Stack: React Native, Expo, TypeScript, modern state management. Native iOS/Android experience is a plus.