Comment by cweagans

I don't think that's true. I opened https://github.com/dokku/dokku/issues/5008 a while back and Jose didn't seem to disagree.

Addressing your argument directly though: you know that if you spin up a Postgres database for your app, you need to dump the database to disk to back it up (or if you wanna get fancy, you can do a delta from the last backup + a full backup periodically). Anytime a Postgres database exists, you know the steps you need to take to backup that service.

Same with persistent file storage on disk: if you have a directory of files, you need a snapshot of all of those files.

Each _service_ can know how to back itself up. If you tell a Dokku _app_ to back itself up, what you really mean is that each _service_ attached to that app should do whatever it needs to do to create a backup. Then, dokku only needs to collate all of the various backup outputs, include a copy of the git repository that drives the app, tar/zstd it, and write it to disk.

As you pointed out, the user should probably be able to control the backup cadence, where those backups are shipped off to, the retention period, whether or not they are encrypted, etc, but the actual mechanics of performing a backup aren't exactly rocket science. All of the user configurable values can have reasonable defaults too -- they can/should Just Work (tm). There's value in having that work OOTB even if the backups are just being written to disk on the actual Dokku machine somewhere.