An anonymous tester reports that, when testing the latest build, attempting to create a voucher throws an HTTP 500 error.

When attempting to reproduce this locally, I noticed the following error in the logs:

allmydata.node.MissingConfigEntry: 'tahoe.cfg' is missing the [storageclient.plugins.privatestorageio-zkapauthz-v1]allowed-public-keys entry

Upon further inspection, I see that the allowed-public-keys values are currently being written to $nodedir/private/servers.yaml when they should instead (as per the error above as well as the ZKAPAuthorizer configuration docs), be written to $nodedir/tahoe.cfg.