Isomorphic Base64

isomorphic-base64 is a compact, zero-dependency utility that provides consistent Base64 encoding and decoding functionality across both Node.js and browser environments. It exports `atob` and `btoa` functions, mirroring the browser's global Web API for Base64 operations. Currently at version 1.0.2, the package was last published over a decade ago (May 2015), indicating a highly stable and mature codebase that has seen no significant breaking changes or feature additions, operating on a maintenance-only release cadence. Its key differentiator is providing a reliable polyfill or abstraction layer, ensuring that applications can perform Base64 transformations uniformly without needing to conditionally implement Node.js's `Buffer` API or rely on the global `window.atob`/`window.btoa` in browsers. It primarily handles ASCII/Latin-1 strings, a common limitation of the native `atob`/`btoa` functions.