Render my custom Vue component

I’ve been trying to follow this guide to create my custom component.
Guide Official

But when I test my component, are not there. just create the div but the component is not loaded in the tree of component of vue.

I create the folder of feature in app/assets/javascript/cool_feature. with index.js and folder component.

And I call the reference in haml files using #js-cool-feature.

The load of the component is automatic? I meant i ran gdk stop webpack and tan yarn run webpack. an then restart gdk restart webpack rails-web. but it does not work. I can’t load my component.