This is part of the NServiceBus Upgrade Guide from Version 9 to 10, which also includes the following individual upgrade guides for specific components:
Transports
Persistence
- Azure Storage Persistence Upgrade Version 6 to 7
- Cosmos DB Persistence Upgrade from 3 to 4
- NHibernate Persistence Upgrade Version 10 to 11
- SQL Persistence Upgrade Version 8 to 9
Other
Saga mapping loading with disabled assembly scanning
When assembly scanning is disabled, saga mapping discovery has been tightened. Previously, all assemblies discovered via GetAvailableTypes() were registered with NHibernate, allowing saga mappings to be picked up from any scanned assembly, even if it did not contain saga entities. Now, saga entity types are resolved first from the registered saga metadata, and only assemblies that actually contain those saga entities are treated as the authoritative source of mappings.
As a result, NHibernate no longer pulls in unrelated mappings from arbitrary scanned assemblies. If you rely on saga-related mappings that live in assemblies which do not directly contain saga entities, those mappings must now be manually registered with NHibernate to ensure they are included.