Angular Elements allows you to create Custom Elements (from the WebComponents spec) from Angular Components.

This means that those components can be used outside of an Angular app!

The project is a standard Angular 6 project with a few additions:

src/app/element.module.ts   Module with the component to be used as Angular Element. Imported by App Module
src/main.element.ts         bootstrap the Element Module
src/polyfills.element.ts    polyfills for the Element Module
build-elements.js           script to generate the exported file and demo project

The component can be developed as any other Angular component: run ng serve and navigate to http://localhost:4200/.

The build configuration of the Angular Elements is defined in a separate project in angular.json.

You can run this configuration with npm run build:elements. It creates a build in dist/elements-build that only contains ElementModule.

After this build the ./build-elements.js script creates the final js file and demo project in dist/elements.