React Native Developer

Role: React Native Developer

Location: Alameda, CA(Hybrid)

Employment Type: C2C or W2

Role Summary

• build and maintain consumer mobile features across iOS and Android using React Native, including CGM data visualization, AI-powered food logging, personalized metabolic insights, and AI health assistant experiences.
• Own your areas of the React Native codebase end to end, from architecture and design through implementation, testing, and ongoing maintenance.
• Write clean, well-tested, performant React Native code that works reliably across a wide range of iOS and Android devices and OS versions.
• Identify and resolve performance issues across the React Native layer, including JavaScript thread bottlenecks, render
• optimization, and memory management.
• Work with native modules and understand how React Native bridges to iOS and Android platform capabilities, including integrations with CGM hardware SDKs and Bluetooth data streams.
• Participate in Lingo's ongoing migration from React Native toward native iOS and Android where appropriate, contributing your perspective on what should migrate and how.
• Conduct code reviews that raise the quality bar across the mobile team, sharing knowledge and holding a high standard for readability, testability, and maintainability.
• Partner with Product and Design to translate requirements into well-scoped, high-quality engineering solutions and push back constructively when scope or approach creates unnecessary complexity.
• Contribute to mobile testing practices, including unit, integration, and end-to-end testing across the React Native layer.

Required Qualification:

Bachelor's degree in computer science, Engineering, or a related technical discipline.

5+ years of professional software engineering experience, with at least 3 years using React Native as a primary technology in a production consumer application. Strong, demonstrable React Native expertise, including component architecture, state management, navigation, performance optimization, and the React Native new architecture (JSI, Fabric, TurboModules).

Working knowledge of iOS and/or Android platform fundamentals, sufficient to understand how React Native interacts with the native layer, read and interpret native code when debugging, and make informed decisions about native module usage.

Experience working with native modules in a React Native application, including consuming existing native modules and understanding how they bridge to platform capabilities.

Solid understanding of mobile application architecture patterns, including state management solutions (Redux, Zustand, or equivalent), navigation libraries, and offline-first design.

Experience with mobile performance profiling and optimization at the React Native layer, including identifying and resolving JavaScript thread and render performance issues.

Experience writing automated tests for React Native applications, including unit and integration tests and familiarity with end-to-end testing frameworks. Preferred Qualifications

Hands-on experience writing native iOS code in Swift or native Android code in Kotlin, beyond reading and debugging into actively building native modules or platform-specific features.

Experience in consumer health, digital health, or regulated industries where software quality has direct implications for end users.

Familiarity with CGM, biosensor, or IoT data integration in mobile applications, particularly real-time data streams from wearable hardware.

Exposure to Bluetooth Low Energy protocols and mobile SDK integration for wearable or connected health devices.

Exposure to on-device AI or ML capabilities such as Core ML or TensorFlow Lite integrated within a React Native application.

Experience with app store release processes for iOS and Android, including CI/CD pipeline integration for mobile builds.

Prior experience at a high-growth consumer technology company or digital health environment.