js2mjs is a development‑time utility that rewrites a compiled ESM codebase from using `.js` files to using `.mjs` files, updating import paths accordingly so the output can run under Node.js with `"type":"module"`. It’s aimed at TypeScript (or other) projects that emit an ES‑module distribution compatible with bundlers but not with Node’s strict file‑extension rules. The tool is intended for developers who need a quick post‑build conversion of their `dist/esm` folder to a Node‑ready `.mjs` layout.