ng-packagr
Compile and package Angular libraries in Angular Package Format (APF)
Compile and package Angular libraries in Angular Package Format (APF). Paths in the ngPackage section are resolved relative to the location of the package.json file. In the above example, public_api.ts is the entry file to the library's sources and must be placed next to package.json (a sibling in the same folder). You can easily run ng-package through a npm/yarn script.