Did you find a solution to this? I am having almost identical crashes, but only on some devices (iPhone 7s and SE). I did not migrate any data, but I am using peristent store with descriptions. I cant recreate the crash myself. Here is my crash log language Exception Type: EXC_BREAKPOINT (SIGTRAP) Exception Codes: 0x0000000000000001, 0x00000001950b6a18 Termination Signal: Trace/BPT trap: 5 Termination Reason: Namespace SIGNAL, Code 0x5 Terminating Process: exc handler [188] Triggered by Thread: 0 Thread 0 name: Thread 0 Crashed: 0 libswiftCore.dylib 0x00000001950b6a18 _assertionFailure(_:_:file:line:flags:) + 492 (AssertCommon.swift:132) 1 libswiftCore.dylib 0x00000001950b6a18 _assertionFailure(_:_:file:line:flags:) + 492 (AssertCommon.swift:132) 2 SPWidgetExtension 0x0000000100471dd4 closure #1 in closure #1 in CoreDataHelper.persistentContainer.getter + 464 (CoreDataHelper.swift:153) 3 SPWidgetExtension 0x0000000100471e18 thunk for @escaping @callee_guaranteed (@guaranteed NSPersistentStoreDescription, @guaranteed Error?) - () + 64 (compiler-generated:0) 4 CoreData 0x000000019775a570 -[NSPersistentStoreCoordinator _doAddPersistentStoreWithDescription:privateCopy:completeOnMainThread:withHandler:] + 1008 (NSPersistentStoreCoordinator.m:1461) 5 CoreData 0x000000019760146c -[NSPersistentStoreCoordinator addPersistentStoreWithDescription:completionHandler:] + 268 (NSPersistentStoreCoordinator.m:1507) 6 CoreData 0x000000019782e880 -[NSPersistentContainer _loadStoreDescriptions:withCompletionHandler:] + 232 (NSPersistentContainer.m:284) 7 CoreData 0x0000000197609658 -[NSPersistentContainer loadPersistentStoresWithCompletionHandler:] + 316 (NSPersistentContainer.m:271) 8 SPWidgetExtension 0x0000000100471bc4 closure #1 in CoreDataHelper.persistentContainer.getter + 620 (CoreDataHelper.swift:151) 9 SPWidgetExtension 0x00000001004717e0 CoreDataHelper.persistentContainer.getter + 40 (CoreDataHelper.swift:144) 10 SPWidgetExtension 0x00000001004657e4 context.get + 4 (CoreDataHelper.swift:27) 11 SPWidgetExtension 0x00000001004657e4 getContext + 28 (WidgetData.swift:274) 12 SPWidgetExtension 0x00000001004657e4 init + 48 (WidgetProvider.swift:21)