I built and shipped end‑to‑end product features across web and mobile using React and React Native, supported by Scala backend services and APIs. I developed responsive, reusable UI components in React and implemented cross‑platform mobile screens in React Native with a focus on performance and usability. I designed and integrated Scala API endpoints and business logic to power client workflows, including validation, error handling, and data processing. I improved application performance by optimizing rendering, state management, and network requests across React and React Native clients. I collaborated with product, design, and QA to deliver production releases, write tests, review code, and troubleshoot issues in production.