How to sell a script and plugins to it under licenses?

Question

CMS

Let's say there is a blog engine that I want to sell under licenses (or whatever it is better in 2021).
Those who bought the basic package can also buy add-ons (plugins).
How to do it right?

Answer 1

in 2021, no one will buy a blog engine at all. especially since there is a free WordPress with any kind of plugins.
In 2001, maybe someone would have bought

Answer 2

You find clients, you sell.

Answer 3

Joomla has a free SW JProject component. It allows you to organize the download of scripts by license keys. If your script allows you to update, then you can make an update server on its basis. For sale there is a bundle with the popular JoomShopping store.