I believe his question was about "does this docker instance then rely on an external service/api to run", which it appears it does, and thus wouldn't quite qualify for fully self hosted.
Many reasons why it's important to know that, the one that matters to me personnaly is because of data storage location requirements.
It does not rely on external api or services, you can run this completely isolated (well you would need a postgres instance). The WindmillHub that Windmill fetch data from is completely unidirectional and something purely out of convenience. In theory shouldn't have an impact in your ability to use the product without it, although we should introduce a flag for the product to not even attempt to list the available scripts from the community if that's your wish. I will write an issue on the roadmap about that.
Ah then I guess my (very quick) look at your link was wrong then, I apologize.
I'm personally from the EU AND in an industry with stricter data control than usual which is why I made that particular point. If that is a possibility for your product then I believe you should absolutely have it somewhere on your roadmap, and then make it extra clear in your "self host" description (things like "on premise", "your data never leaves your server", "retain control of your data", ...). It's usually a lot easier to do it early and stand by it than try to make it possible later.
Yes one of our primary target is actually clients with regulatory, compliant or ethical concerns to not control all of their data on-prem. By being open-source and self-hostable, we can meet those standards. I am from France myself and am pretty sensitive about the data privacy issues.
Many reasons why it's important to know that, the one that matters to me personnaly is because of data storage location requirements.