Summary

@microsoft/api-extractor@7.57.0 ships ESM entry points (lib-esm/) with extensionless imports, which breaks Node.js ESM module resolution.

The package's exports field correctly points to lib-esm/index.js:

".": {
  "import": "./lib-esm/index.js",
  "require": "./lib-commonjs/index.js"
}

But lib-esm/index.js contains extensionless imports like:

export { ConsoleMessageId } from './api/ConsoleMessageId';

Node.js ESM requires explicit .js extensions, so this fails with:

Error [ERR_MODULE_NOT_FOUND]: Cannot find module
'.../node_modules/@microsoft/api-extractor/lib-esm/api/ConsoleMessageId'
imported from .../node_modules/@microsoft/api-extractor/lib-esm/index.js

This is a regression from v7.56.3 where this worked correctly.

Repro steps

1. Create a project with "type": "module" in package.json
2. Install @microsoft/api-extractor@7.57.0
3. Import from @microsoft/api-extractor in an ESM context (e.g. via vite-plugin-dts)
4. Run with Node.js v22+

Expected result: Module resolves successfully.

Actual result:

Error [ERR_MODULE_NOT_FOUND]: Cannot find module
'/path/node_modules/@microsoft/api-extractor/lib-esm/api/ConsoleMessageId'

Workaround: Pin @microsoft/api-extractor to 7.56.3.

Standard questions

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