Seafile ‘scrambles’ files and doesn’t make them available to other applications on the host, which I don’t think OP wants.

I have my storage mounted from my NAS using NFS and this is added to Nextcloud using the External Storage plugin. Works great.

The next release of TrueNAS SCALE in October is dropping Kubernetes in favour of plain Docker/Docker Compose. That may be worth a look?

That’s good to hear. Looks like something worth revisiting once it’s been tested well.

I would have used Owncloud Infinite Scale but the fact you can’t use your own existing files makes it a complete non-starter for me. I don’t want my files locked behind Decomposed FS.

Unless I’ve read things wrong, which is entirely possible.