@Daniel Gafni showed me how to do this with dagster. I notice that ‘PartitionMappings’ are experimental API. They are missing from the docs on the website. Is there any plans to make this non experimental?

They should be on the docs site. I'll add them. We don't have a particular date in mind for unexperimentalizing them - we just want to see them be used and have the opportunity to hammer out any problems before marking them stable