Worked on stabilizing the matrix-js-sdk repository for React Native environments using Hermes, focusing on improving mobile SDK reliability. Addressed a critical startup crash by replacing improper use of Promise.finally() with a two-argument .then(onFulfilled, onRejected) pattern in TypeScript, ensuring that session recalculation logic executes consistently regardless of promise outcome. Added regression tests to verify that session member recalculation remains robust after promise rejections, specifically targeting Hermes-related TypeErrors. Enhanced documentation and test coverage around MatrixRTCSession management, reinforcing cross-platform RTC session stability. Demonstrated disciplined commit practices and a methodical approach to front end development, prioritizing business value and developer confidence.