Homey Cloud with custom/unsupported/virtual devices

I’d like to use Homey Cloud with devices that are currently not supported by any of the apps in the App Store.

Is there a way to create some “dummy devices” that I could hook up to my own server?
The closest I got was to create my own Home Assistant instance with proxy etc, and import a device from there, but it’s a major hack IMO :frowning:

It would be nice if it was flexible enough that it’s not only the big (and very limited) brands that are supported.

Homey cloud = limited
Homey Pro = less limited