More info: The issue happened when I added an attribute in an entity. And also happened when adding an entity to the same model. The code I'm using to add the persistent store is: try persistentCoordinator.addPersistentStore(ofType: NSInMemoryStoreType, configurationName: "InMemoryStore", at: nil, options: myOptions) try persistentCoordinator.addPersistentStore(ofType: NSSQLiteStoreType, configurationName: "PersistentStore", at: myGroupURL, options: myOptions) In case it fails, I delete the DB and recreate it.

Update on this Q: Apple replied to a feedback I opened saying Xcode does not have official support for Rosetta. I had no option but to put an enormous effort into adding support to Apple Silicon Macs. Thanks, Apple.