[t-8ch]

Hi,

I would like to develop a mechanism for Calibre to discover and use systemwide installed plugins in addition to builtin plugins and plugins loaded from the users settings.

This would allow users and Linux distributions to package third-party plugins the same way as the rest of the system, including custom distribution or pip package repositories.

My primary idea is to use the existing setuptools discovery mechanism for plugins: pkg_resource entrypoints.
This is the standard Python way, does not require any dependencies and should always work.
The only disadvantage I can see is that existing plugins probably don't have setuptools metadata. But that should be easy to add, first downstream by people packaging the plugins and later directly inside the plugins repository.

I am willing to implement this feature and see it through, but first I'd like to get feedback from the Calibre team whether this has a chance of being accepted.

Thanks