Valdi is a cross-platform UI framework developed by Snapchat that aims to deliver native performance while maintaining fast development speeds. It allows developers to write UI components in TypeScript, which compile directly to native views for iOS, Android, and macOS. This eliminates reliance on web views or JavaScript bridges, leading to more efficient applications. Valdi has been in beta for eight years and is currently used in Snap's production apps, with plans for a full release pending further testing and documentation improvements. The framework boasts several performance-enhancing features. It includes automatic view recycling, which significantly reduces latency by reusing native views. Components can re-render independently, preventing unnecessary updates to parent components. Valdi's C++ layout engine minimizes processing overhead, and its viewport-aware rendering ensures only visible views are activated, making features like infinite scrolling more efficient. Developers can expect instant hot reload capabilities, allowing them to see changes immediately across platforms without recompilation. Valdi also integrates seamlessly into existing applications, enabling developers to incorporate Valdi components into native app architectures or vice versa. It supports writing performance-critical code in languages like C++, Swift, and Kotlin, with type-safe bindings to TypeScript, which simplifies interactions between native code and TypeScript. Other notable features include advanced animations, a built-in testing framework, and support for worker threads, allowing for multi-threaded JavaScript execution. The framework's design emphasizes both performance and developer experience, making it a practical choice for modern app development.