b64u-lite is an extremely lightweight, isomorphic base64url library (531 bytes) designed for Node, browser, and React Native environments. It provides essential functions for encoding and decoding base64url strings, with optional padding support, making it ideal for developers who need a minimal, efficient solution for base64url operations in their projects. This library is particularly useful for developers working on web applications, Node.js services, or React Native apps where bundle size and performance are critical.