babel-preset-gatsby-package

Babel preset used internally by Gatsby for developing Gatsby packages. It bundles @babel/preset-env, @babel/preset-react, @babel/preset-flow, and several plugins (class properties, optional chaining, transform-runtime). Designed for package authors, not Gatsby site users. Current stable version is 3.16.0, part of Gatsby v5 ecosystem. Released on npm alongside Gatsby releases (~monthly). Supports Node 18+. Key differentiator: automatically configures browser vs Node targets via the `browser` option, tailored for Gatsby package development rather than general React apps.