React Native EU 2021 - Virtual Conference: Day II

Microsoft engineers Lorenzo Chandra and Tommy describe brownfield development, where teams build React Native features in separate repositories and integrate them into host apps such as Outlook and Teams. React Native Test App lets developers work without building a full host app, and rnx-kit check helps align package versions and fix dependency configuration across monorepos.

Callstack developer Paweł Trzciwa explains how code splitting can load features on demand in modular apps, super apps, and hardware companion apps. He presents Re.Pack, a webpack-based React Native solution, and outlines async chunks, dynamic scripts, and Module Federation. At the time of the talk, basic local and remote chunk loading was available, while Module Federation was planned.

Monica compares Flipper, React Native Debugger, and Reactotron, covering their plugins, breakpoints, profiling, and tradeoffs such as setup and performance overhead. Grant Sander demonstrates Reanimated 2 worklets, shared values, and gesture handling; Alexander Kotik compares React Native Animated, Lottie, and Reanimated for building purposeful animations that run smoothly.

Matthias Ingiro shows how app packages, Hermes bytecode, and stored data can be inspected, and discusses tools such as MobSF, Frida, and Objection. Thor from Stripe demonstrates PaymentSheet in an Expo app and explains that native UI handles card details without exposing them to the JavaScript bridge. He notes that digital goods generally require the app stores’ in-app purchase systems.

Louis Rusevsky demonstrates test-driven development with React Native Testing Library, using a Hacker News app to test story switching and link behavior. Lars Thorup presents recorded Bluetooth traffic as reusable integration-test data, reducing dependence on manual mocks. Akshat Paul and Wojciech Kwiatek cover WebRTC video and VoIP, including signaling, STUN and TURN, permissions, and native call handling.