Transmogrifier without Plone? (ETL Pipeline construction with transmogrifier)?

I am interested in using collective.transmogrifier · PyPI for my next migration task, wihich to (sadly) take plone content and push it into another CMS that's not Plone.

(ARC XP is the next move for us for those wondering)

I noticed for quite a while that the official docs have:

Note that a transmogrifier pipeline can be used to process any number of things, and is not specific to Plone content import. However, it’s original intent is to provide a pluggable way to import legacy content.

I'm making progress looking at the tests and other examples, but if anyone has a complete example of a transmogrifier pipeline without a plone context, I'd be quite interested to take a look.

It might also be useful for colloective.transmogrifier to have some docs and examples for this 'process any number of things' use case, which I find fascinating in itself. The broader migration community would certainly love some kind of data migration (the new kids are calling it ETL Pipelines now).

Edited the title to get some google love for "ETL" google searches, which land you on a bunch of companies promising you custom ETL solutions for a low-low-price. This is what transmogrifier does.