[eschwartz]

You will want to have backups, of course. But the copy in calibre doesn't get edited -- any changes you make in calibre are written to the database, not the ebook, and only applied to the ebook's COPY when you send it to a new device. Even Polish ebook, or an epub-to-epub convert, creates a .original_epub to save the old version.

Unless you use Tweak ebook, in which case you've opened up calibre's copy for editing.


If you, for example, use Dropbox to back up your calibre library, that might be enough right there. Any changes you make to the calibre library will be synced, so all your books get added to Dropbox, and if you don't edit them, they will remain the same book you first added. Even if you do edit them, you might not care about the old version.