"You don't do a "migration script" for a filesystem, you release the new version of the filesystem"
here's how i upgrade my filesystem:
```
$ zpool upgrade hetznerBackupPool
This system supports ZFS pool feature flags.
Enabled the following features on 'hetznerBackupPool':
zilsaxattr
head_errlog
blake3
block_cloning
vdev_zaps_v2
```