What's Changed

@nestjs/mapped-types is now a native ES module, and the major version is aligned with the Nest 12 release line (there is no 3.x — 2.1.1 goes straight to 12.0.0).

ESM migration

The package is published as pure ESM ("type": "module", compiled with NodeNext) behind a proper exports map. The legacy root index.js / index.d.ts shims are gone, and deep imports into build internals are no longer resolvable — import from the package root.

require(esm) — CommonJS still works

You do not need to convert your app to ESM. Thanks to Node's require(esm) support, this keeps working:

const { PartialType } = require('@nestjs/mapped-types');