Certain directories within a jail can be swapped out to (datasets) "outside". This means that this data is stored independently of the jail. The goal is, similar to Docker, to be as little dependent as possible on the jail itself.

This way, if the jail is corrupted or deleted for some reason, we are able to restore the previous configuration and data with minimal effort. How this can be achieved (generically) I have described here and the Gitea article added the two directories that can be offloaded externally.