Senior React Native / Expo Engineer

Mochi Health•San Francisco, CA

11d•$230,000 - $330,000•Onsite

About The Position

Mochi Health is seeking a Senior React Native / Expo Engineer to join their team. The company is building an AI-driven marketplace to improve healthcare accessibility, focusing on connecting patients with providers, transparent pharmacy pricing, and affordable medications. They have experienced rapid growth and are expanding into preventative healthcare areas like hormone optimization, longevity medicine, and peptide therapies. The role involves owning the mobile applications that serve as the primary daily touchpoint for patients and providers, architecting solutions for sensitive biometric tracking, secure communication, and complex medication management. Mochi Health emphasizes a high talent density environment with significant leverage for its engineering team, aiming to rebuild healthcare from the patient's perspective.

Requirements

5-7+ years of frontend engineering experience with a deep, specialized focus on React Native and Expo.
Experience building, shipping, and maintaining complex, data-heavy mobile applications in production.
Expertise in the modern Expo ecosystem, including managing EAS builds and integrating complex native modules without ejecting.
Understanding of iOS App Store and Google Play Store review guidelines.
Mastery of mobile state and performance, including React render cycle, UI thread optimization, list rendering, and asynchronous data fetching.
Experience with full lifecycle ownership, including CI/CD pipelines, crash rate monitoring (e.g., Sentry), and app reliability.
Experience using frontier agentic AI tools (e.g., Codex 5.3, Claude Opus 4.6) to accelerate development and ability to audit/verify AI output.
Low ego, high standards, and excellent communication skills.
Ability to thrive in cross-functional environments with healthcare regulations, compliance, and patient safety considerations.
Willingness to work in-person 5 days a week in the San Francisco office.

Nice To Haves

Experience with native iOS (Swift/Objective-C) or Android (Kotlin/Java) development.
Demonstrated track record of setting technical direction across teams.
Experience navigating deep ambiguity.
Proven ability to measurably level up engineers around you.

Responsibilities

Architect the Mobile Clinical Experience: Build dynamic, high-performance mobile tools for patients and providers, integrating with Apple HealthKit and Google Health Connect for real-time data, and developing secure messaging systems.
Leverage the Expo Ecosystem: Utilize Expo and EAS for a unified cross-platform experience, managing build pipelines, custom native modules, and over-the-air updates.
Design for the Edge: Architect robust, offline-first data synchronization strategies and implement aggressive local caching for reliable access to care plans, even with spotty connections.
Champion the Mobile UX: Focus on premium, native app feel, optimizing frame rates, navigation transitions, keyboard avoidance, and accessibility standards.
Build Agentic Workflows: Integrate AI capabilities into mobile interfaces to automate clinical operations and streamline patient support, utilizing frontier agentic models.
Raise the Engineering Bar: Own key mobile architectural decisions, establish patterns for code reuse between web and mobile clients, and elevate engineers through code review and testing practices.