I would prefer first-class support for self publishing. Want to install some app, open some-app.com in a browser, and click "download" button.
Since the parent mentioned Debian: this is the model that Debian provides (and yum as well), and Ubuntu extensively uses: https://help.ubuntu.com/community/AptURL
Open some-app.com in a browser, click the apt:// button, and the system will not only install the requested app, but also use the configured channel for updating your apps.
There are numerous improvements to be made in this area, for example to automatically pin a package to an origin, or to limit third-party origins to only installing in /opt/$origin, but the mechanism has been available for two decades.
Since the parent mentioned Debian: this is the model that Debian provides (and yum as well), and Ubuntu extensively uses: https://help.ubuntu.com/community/AptURL
Open some-app.com in a browser, click the apt:// button, and the system will not only install the requested app, but also use the configured channel for updating your apps.
There are numerous improvements to be made in this area, for example to automatically pin a package to an origin, or to limit third-party origins to only installing in /opt/$origin, but the mechanism has been available for two decades.