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 10 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.
To change the target of the compiled js file to either es5 or es2015, update the "postbuild:elements" script in package.json. Default it creates an es2015 file.