How to properly backup my addon?

I develop addon and wants Hassio to seamlessly backup it’s data, so users does not need to configure something only for my addon.

I read Developing an add-on | Home Assistant Developer Docs but backup is mentioned only in some config options without actually explaining how Hassio backup addons and what addon developer should do to support it.

Is it explained somewhere else?
Could you explain it here? :slight_smile: