Currently, this is only possible with the NHibernate persister and a custom mapping.
it's worth noting that append only data models can work out of the box with RavenDB as RavenDB OCC kicks in only if the saga data instance has been touched/modified.
@mauroservienti not saying that RavenDB does not support append only by adding new documents its that none of our saga persister implementations support append only natively.
Feedback for 'Saga concurrency' https://docs.particular.net/nservicebus/sagas/concurrency
Location in GitHub: https://github.com/Particular/docs.particular.net/blob/master/nservicebus/sagas/concurrency.md
In Create an append only Saga Model it's stated that:
it's worth noting that append only data models can work out of the box with RavenDB as RavenDB OCC kicks in only if the saga data instance has been touched/modified.