How to wire SwiftData up to external data sources?

In one of the WWDC 2023 videos a presenter said in passing that you can connect SwiftData to whatever complicated setup you have. I haven't been able to find any documentation or connection points for this though.

Obviously I can fetch the data myself and call context.insert(...) for every item, but what about refreshes, deletes, inserts, updates? Where can I wire up these external calls and their responses?

Thanks!

Apple added docs about read-only server side data: https://developer.apple.com/documentation/swiftdata/maintaining-a-local-copy-of-server-data

I'm still not sure how one would integrate for read/write.

How to wire SwiftData up to external data sources?
 
 
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