If you are hosting your own software to provide add-ons, styles or languages for XenForo, you may hook into Install & Upgrade by providing your own Install & Upgrade handler. You may push it to our GitHub repository and we’ll bundle it up with the next release, or you can release it as a separate add-on that hooks into Install & Upgrade.
You can find a number of interfaces in `ThemeHouse/InstallAndUpgrade/InstallAndUpgrade/Interfaces`. You may implement any of them as you need. Common implementations and tools can be found in `ThemeHouse/InstallAndUpgrade/InstallAndUpgrade/Traits`.
Install & Upgrade detects available handlers via the `th_installupgrade_handler` content type.