I have one target building and filling the SwiftData store and then copying the same store file to another target of the app to use the contents. That worked fine from iOS 17 to iOS 26.0.1 Under iOS 26.1 I am getting following error: CoreData: error: This store file was previously used on a build with Persistence-1522 but is now running on a build with Persistence-1518. file:///Users/xxx/Library/Developer/CoreSimulator/Devices/0FE92EA2-57FA-4A5E-ABD0-DAB4DABC3E02/data/Containers/Data/Application/B44D3256-9B09-4A60-94E2-C5F11A6519E7/Documents/default.store What does it mean and how to get back to working app under iOS 26.1?

Here is what I thought I want to give each user a unique container, when the user login or register, the user could isolate their data in specific container. I shared the container in a singleton actor, I found it's possible to update the container in that actor. But I think it won't affect the modelContext which is in the Environment. Does SwiftData allow me or recommend to do that?

After Xcode 26.1 was updated and installing the OS 26.1 simulators, my app started crashing related to transformable properties. When I checked my schema, I noticed that properties with array collection types are suddenly set with an option transformable with Optional("NSSecureUnarchiveFromData")], even though I do not use any transformable types. I verified the macros, no transformable was specified. This is causing ModelCoders to encode/decode my properties incorrectly. This is not an issue when I switch back to OS 26.0 simulators.

Hello, In our app, we’ve modeled our schema using inheritance introduced in iOS 26.0, and we’re implementing SwiftData History to re-fetch models only when necessary. @Model public class Transaction { @Attribute(.preserveValueOnDeletion) public var date: Date = Date() public var amount: Double = 0 public var memo: String? } @Model public final class Spending: Transaction { public var installmentIndex: Int = 1 public var installment: Int = 1 public var installmentID: UUID? } If data has been deleted from database, we need to check a date property to determine whether to re-fetch datas. To do this, we added the preserveValueOnDeletion attribute to date property so we could retrieve it from the History tombstone value. However, after adding this attribute, a crash occurs. There is a console log Could not cast value of type 'Swift.ReferenceWritableKeyPath<Shared.ModelSchemaV5.Transaction, Foundation.Date>' (0x106bf8328) to 'Swift.PartialKeyPath<Shared.ModelSchemaV5.Spending>' (0x1094f21d8). and error log attached StrictMoneyChecking-2025-11-07-105108.txt I also tried this in the recent SampleTrip app, and fetching all history after a deletion causes the same crash. Is this issue currently being worked on or under investigation?

When I used to do Migrations, I always used ETL and then push to a dev system to review/test before going production. The migration support is SwiftData is fine for a little tweak. I might as well just just use new schema and context and write the custom code than use the SwiftData migration support.

Hi there! I'm making an app that stores data for the user's profile in SwiftData. I was originally going to use UserDefaults but I thought SwiftData could save Images natively but this is not true so I really could switch back to UserDefaults and save images as Data but I'd like to try to get this to work first. So essentially I have textfields and I save the values of them through a class allProfileData. Here's the code for that: import SwiftData import SwiftUI @Model class allProfileData { var profileImageData: Data? var email: String var bio: String var username: String var profileImage: Image { if let data = profileImageData, let uiImage = UIImage(data: data) { return Image(uiImage: uiImage) } else { return Image("DefaultProfile") } } init(email:String, profileImageData: Data?, bio: String, username:String) { self.profileImageData = profileImageData self.email = email self.bio = bio self.username = username } } To save this I create a new class (I think, I'm new) and save it through ModelContext import SwiftUI import SwiftData struct CreateAccountView: View { @Query var profiledata: [allProfileData] @Environment(\.modelContext) private var modelContext let newData = allProfileData(email: "", profileImageData: nil, bio: "", username: "") var body: some View { Button("Button") { newData.email = email modelContext.insert(newData) try? modelContext.save() print(newData.email) } } } To fetch the data, I originally thought that @Query would fetch that data but I saw that it fetches it asynchronously so I attempted to manually fetch it, but they both fetched nothing import SwiftData import SwiftUI @Query var profiledata: [allProfileData] @Environment(\.modelContext) private var modelContext let fetchRequest = FetchDescriptor<allProfileData>() let fetchedData = try? modelContext.fetch(fetchRequest) print("Fetched count: \(fetchedData?.count ?? 0)") if let imageData = profiledata.first?.profileImageData, let uiImage = UIImage(data: imageData) { profileImage = Image(uiImage: uiImage) } else { profileImage = Image("DefaultProfile") } No errors. Thanks in advance

If an app is using top-level models, meaning they exist outside the VersionedSchema enum, is it safe to keep them outside of the VersionedSchema enum and use a migration plan for simple migrations. Moving the models within the VersionedSchema enum I believe would change the identity of the models and result in data being lost, although correct me if I'm wrong in that statement. The need presently is just to add another variable to the model and then set that variable within the init function: var updateId = UUID() The app is presently in TestFlight although I'd like to preserve data for users that are currently using the app. The data within SwiftData is synchronized with CloudKit and so I'd also like to avoid any impact to synchronization. Any thoughts on this would be greatly appreciated.

I've run into a strange issue. If a sheet loads a view that has a SwiftData @Query, and there is an if statement in the view body, I get the following error when running an iOS targetted SwiftUI app under MacOS 26.1: Set a .modelContext in view's environment to use Query While the view actually ends up loading the correct data, before it does, it ends up re-creating the sqlite store (opening as /dev/null). The strange thing is that this only happens if there is an if statement in the body. The statement need not ever evaluate true, but it causes the issue. Here's an example. It's based on the default xcode new iOS project w/ SwiftData: struct ContentView: View { @State private var isShowingSheet = false var body: some View { Button(action: { isShowingSheet.toggle() }) { Text("Show Sheet") } .sheet(isPresented: $isShowingSheet, onDismiss: didDismiss) { VStack { ContentSheetView() } } } func didDismiss() { } } struct ContentSheetView: View { @Environment(\.modelContext) private var modelContext @Query public var items: [Item] @State var fault: Bool = false var body: some View { VStack { if fault { Text("Fault!") } Button(action: addItem) { Label("Add Item", systemImage: "plus") } List { ForEach(items) { item in Text(item.timestamp, format: Date.FormatStyle(date: .numeric, time: .standard)) } } } } private func addItem() { withAnimation { let newItem = Item(timestamp: Date()) modelContext.insert(newItem) } } } It requires some data to be added to trigger, but after adding it and dismissing the sheet, opening up the sheet with trigger the Set a .modelContext in view's environment to use Query. Flipping on -com.apple.CoreData.SQLDebug 1 will show it trying to recreate the database. If you remove the if fault { Text("Fault!") } line, it goes away. It also doesn't appear to happen on iPhones or in the iPhone simulator. Explicitly passing modelContext to the ContentSheetView like ContentSheetView().modelContext(modelContext) also seems to fix it. Is this behavior expected?

Hi all... The app I'm building is not really a beginner level test app, it's intended to be published so I want everything to be done properly while I'm both learning and building the app. I'm new to swift ecosystem but well experienced with python and JS ecosystems. These two models are causing my app to crash @Model final class CustomerModel { var id: String = UUID().uuidString var name: String = "" var email: String = "" var phone: String = "" var address: String = "" var city: String = "" var postalCode: String = "" var country: String = "" @Relationship(deleteRule: .nullify) var orders: [OrderModel]? @Relationship(deleteRule: .nullify) var invoices: [InvoiceModel]? init() {} } @Model final class OrderModel { var id: String = UUID().uuidString var total: Double = 0 var status: String = "processing" var tracking_id: String = "" var order_date: Date = Date.now var updated: Date = Date.now var delivery_date: Date? var active: Bool = true var createdAt: Date = Date.now var items: [OrderItem]? @Relationship(deleteRule: .nullify) var invoice: InvoiceModel? @Relationship(deleteRule: .nullify) var customer: CustomerModel? init() {} } both referenced in this model: @Model final class InvoiceModel{ var id: String = UUID().uuidString var status: String = "Pending" var comment: String = "" var dueDate: Date = Date.now var createdAt: Date = Date.now var updated: Date = Date.now var amount: Double = 0.0 var paymentTerms: String = "Once" var paymentMethod: String = "" var paymentDates: [Date] = [] var numOfPayments: Int = 1 @Relationship(deleteRule: .nullify, inverse: \OrderModel.invoice) var order: OrderModel? @Relationship(deleteRule: .nullify) var customer: CustomerModel? init() {} } This is my modelContainer in my index structure: @main struct Aje: App { var appContainer: ModelContainer = { let schema = Schema([UserModel.self, TaskModel.self, SubtaskModel.self, InventoryModel.self, SupplierModel.self]) let config = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false, allowsSave: true, groupContainer: .automatic, cloudKitDatabase: .automatic) do{ return try ModelContainer(for: schema, configurations: [config]) }catch{ fatalError("An error has occured: \(error)") } }() var body: some Scene { WindowGroup { ContentView() } .modelContainer(appContainer) } } This works fine but the below after adding the problematic models crashes the app unless CloudKit is disabled @main struct Aje: App { var appContainer: ModelContainer = { let schema = Schema([UserModel.self, TaskModel.self, SubtaskModel.self, InventoryModel.self, SupplierModel.self, InvoiceModel.self, OrderModel.self, CustomerModel.self]) let config = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false, allowsSave: true, groupContainer: .automatic, cloudKitDatabase: .automatic) do{ return try ModelContainer(for: schema, configurations: [config]) }catch{ fatalError("An error has occured: \(error)") } }() var body: some Scene { WindowGroup { ContentView() } .modelContainer(appContainer) } }

Apple WTF? What did you do to all my Apps? none of them work in iOS26.1 (all worked in 26.0). XCode simply says: CoreData: error: addPersistentStoreWithType:configuration:URL:options:error: returned error NSCocoaErrorDomain (134140) * SwiftData is supposed to do all these automatically 🤷🏻

Hello 👋, I encounter the "This model instance was invalidated because its backing data could no longer be found the store" crash with SwiftData. Which from what I understood means I try to access a model after it has been removed from the store (makes sense). I made a quick sample to reproduce/better understand because there some case(s) I can't figure it out. Let's take a concrete example, we have Home model and a Home can have many Room(s). // Sample code @MainActor let foo = Foo() // A single reference let database = Database(modelContainer: sharedModelContainer) // A single reference @MainActor class Foo { // Properties to explicilty keep reference of model(s) for the purpose of the POC var _homes = [Home]() var _rooms = [Room]() func fetch() async { let homes = await database.fetch().map { sharedModelContainer.mainContext.model(for: $0) as! Home } print(ObjectIdentifier(homes[0]), homes[0].rooms?.map(\.id)) // This will crash here or not. } // Same version of a delete function with subtle changes. // Depending on the one you use calling delete then fetch will result in a crash or not. // Keep a reference to only homes == NO CRASH func deleteV1() async { self._homes = await database.fetch().map { sharedModelContainer.mainContext.model(for: $0) as! Home } await database.delete() } // Keep a reference to only rooms == NO CRASH func deleteV2() async { self._rooms = await database.fetch().map { sharedModelContainer.mainContext.model(for: $0) as! Home }[0].rooms ?? [] await database.delete() } // Keep a reference to homes & rooms == CRASH 💥 func deleteV3() async { self._homes = await database.fetch().map { sharedModelContainer.mainContext.model(for: $0) as! Home } self._rooms = _homes[0].rooms ?? [] // or even only retain reference to rooms that have NOT been deleted 🤔 like here "id: 2" make it crash // self._rooms = _homes[0].rooms?.filter { r in r.id == "2" } ?? [] await database.delete() } } Calling deleteV() then fetch() will result in a crash or not depending on the scenario. I guess I understand deleteV1, deleteV2. In those case an unsaved model is served by the model(for:) API and accessing properties later on will resolve correctly. The doc says: "The identified persistent model, if known to the context; otherwise, an unsaved model with its persistentModelID property set to persistentModelID." But I'm not sure about deleteV3. It seems the ModelContext is kind of "aware" there is still cyclic reference between my models that are retained in my code so it will serve these instances instead when calling model(for:) API ? I see my home still have 4 rooms (instead of 2). So I then try to access rooms that are deleted and it crash. Why of that ? I mean why not returning home with two room like in deleteV1 ? Because SwiftData heavily rely on CoreData may be I miss a very simple thing here. If someone read this and have a clue for me I would be extremely graceful. PS: If someone wants to run it on his machine here's some helpful code: // Database let sharedModelContainer: ModelContainer = { let schema = Schema([ Home.self, Room.self, ]) let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false) debugPrint(modelConfiguration.url.absoluteString.replacing("%20", with: "\\ ")) return try! ModelContainer(for: schema, configurations: [modelConfiguration]) }() extension Database { static let shared = Database(modelContainer: sharedModelContainer) } @ModelActor actor Database { func insert() async { let r1 = Room(id: "1", name: "R1") let r2 = Room(id: "2", name: "R2") let r3 = Room(id: "3", name: "R3") let r4 = Room(id: "4", name: "R4") let home = Home(id: "1", name: "My Home") home.rooms = [r1, r2, r3, r4] modelContext.insert(home) try! modelContext.save() } func fetch() async -> [PersistentIdentifier] { try! modelContext.fetchIdentifiers(FetchDescriptor<Home>()) } @MainActor func delete() async { let mainContext = sharedModelContainer.mainContext try! mainContext.delete( model: Room.self, where: #Predicate { r in r.id == "1" || r.id == "4" } ) try! mainContext.save() // 🤔 Calling fetch here seems to solve crash too, force home relationship to be rebuild correctly ? // let _ = try! sharedModelContainer.mainContext.fetch(FetchDescriptor<Home>()) } } // Models @Model class Home: Identifiable { @Attribute(.unique) public var id: String var name: String @Relationship(deleteRule: .cascade, inverse: \Room.home) var rooms: [Room]? init(id: String, name: String, rooms: [Room]? = nil) { self.id = id self.name = name self.rooms = rooms } } @Model class Room: Identifiable { @Attribute(.unique) public var id: String var name: String var home: Home? init(id: String, name: String, home: Home? = nil) { self.id = id self.name = name self.home = home } }

I'm experiencing the following error with my SwiftData container when running a build: Code=134504 "Cannot use staged migration with an unknown model version." Code Structure - Summary I am using a versionedSchema to store multiple models in SwiftData. I started experiencing this issue when adding two new models in the newest Schema version. Starting from the current public version, V4.4.6, there are two migrations. Migration Summary The first migration is to V4.4.7. This is a lightweight migration removing one attribute from one of the models. This was tested and worked successfully. The second migration is to V5.0.0. This is a custom migration adding two new models, and instantiating instances of the two new models based on data from instances of the existing models. In the initial testing of this version, no issues were observed. Issue and Steps to Reproduce Reproduction of issue: Starting from a fresh build of the publicly released V4.4.6, I run a new build that contains both Schema Versions (V4.4.7 and V5.0.0), and their associated migration stages. This builds successfully, and the container successfully migrates to V5.0.0. Checking the default.store file, all values appear to migrate and instantiate correctly. The second step in reproduction of the issue is to simply stop running the build, and then rebuild, without any code changes. This fails to initialize the model container every time afterwards. Going back to the simulator after successive builds are stopped in Xcode, the app launches and accesses/modifies the model container as normal. Supplementary Issue: I have been putting up with the same, persistent issue in the Xcode Preview Canvas of "Failed to Initialize Model Container" This is a 5 in 6 build issue, where builds will work at random. In the case of previews, I have cleared all data associated with all previews multiple times. The only difference being that the simulator is a 100% failure rate after the initial, successful initialization. I assume this is due to the different build structure of previews. Lastly, of note, the Xcode previews fail at the same line in instantiating the model container as the simulator does. From my research into this issue, people say that the Xcode preview is instantiating from elsewhere. I do have a separate model container set up specifically for canvas previews, but the error does not occur in that container, but rather the app's main container. Possible Contributing Factors & Tested Facts iOS: While I have experienced issues with SwiftData and the complier in iOS 26, I can rule that out as the issue here. This has been tested on simulators running iOS 18.6, 26.0.1, and 26.1, all encountering failures to initialize model container. While in iOS 18, subsequent builds after the successful migration did work, I did eventually encounter the same error and crash. In iOS 26.0.1 and 26.1, these errors come immediately on the second build. Container Initialization for V4.4.6 do { container = try ModelContainer( for: Job.self, JobTask.self, Day.self, Charge.self, Material.self, Person.self, TaskCategory.self, Service.self, migrationPlan: JobifyMigrationPlan.self ) } catch { fatalError("Failed to Initialize Model Container") } Versioned Schema Instance for V4.4.6 (V4.4.7 differs only by versionIdentifier) static var versionIdentifier = Schema.Version(4, 4, 6) static var models: [any PersistentModel.Type] { [Job.self, JobTask.self, Day.self, Charge.self, Material.self, Person.self, TaskCategory.self, Service.self] } Container Initialization for V5.0.0 do { let schema = Schema([Jobify.self, JobTask.self, Day.self, Charge.self, MaterialItem.self, Person.self, TaskCategory.self, Service.self, ServiceJob.self, RecurerRule.self]) container = try ModelContainer( for: schema, migrationPlan: JobifyMigrationPlan.self ) } catch { fatalError("Failed to Initialize Model Container") } Versioned Schema Instance for V5.0.0 static var versionIdentifier = Schema.Version(5, 0, 0) static var models: [any PersistentModel.Type] { [ JobifySchemaV500.Job.self, JobifySchemaV500.JobTask.self, JobifySchemaV500.Day.self, JobifySchemaV500.Charge.self, JobifySchemaV500.Material.self, JobifySchemaV500.Person.self, JobifySchemaV500.TaskCategory.self, JobifySchemaV500.Service.self, JobifySchemaV500.ServiceJob.self, JobifySchemaV500.RecurerRule.self ] } Addressing Differences in Object Names Type-aliasing: All my model types are type-aliased for simplification in view components. All types are aliased as 'JobifySchemeV446.<#Name#>' in V.4.4.6, and 'JobifySchemaV500.<#Name#>' in V5.0.0 Issues with iOS 26: My type-aliases dating back to iOS 17 overlapped with lower level objects in Swift, including 'Job' and 'Material'. These started to be an issue with initializing the model container when running in iOS 26. The type aliases have been renamed since, however the V4.4.6 build with the old names runs and builds perfectly fine in iOS 26 If there is any other code that may be relevant in determining where this error is occurring, I would be happy to add it. My current best theory is simply that I have mistakenly omitted code relevant to the SwiftData Migration.

We have an unreleased SwiftData app for iOS18+. While we were testing I saw reports on the forum about unexpected database migrations for codable arrays on iOS26.1. I'd like to ask a couple of questions: 1- Does this issue originate from the new Xcode version, or is it specific to iOS 26.1? 2- Is it possible to change our attribute so that users on older iOS versions receive the same model, preventing a migration from being triggered when they upgrade to iOS 26.1? One of our models looks like this: struct Point: Codable, Hashable { let x: Int let y: Int } @Model class Grid { private(set) var gridId: String = "" var points: [Point] = [] var updatedAt: Date = Date() private(set) var createdAt: Date = Date() #Index<Grid>([\.gridId]) ... } I can think of some options like: // 1 @Attribute(.transformable(by: CustomJsonTransformer.self)) var points: [Point] = [] // 2 @Attribute(.externalStorage) var points: [Point] = [] // 3 var points: Data = Data() // store points as data However, I'm not sure which one to use. What would you recommend to handle this, or is there a better strategy you would suggest?

Hi Given a simple multiplatform app about Mushrooms, stored in SwiftData, hosted in iCloud using a TextEditor @Model final class Champignon: Codable { var nom: String = "" ../.. @Attribute(.externalStorage) var attributedStringData: Data = Data() var attributedString: AttributedString { get { do { return try JSONDecoder().decode(AttributedString.self, from: attributedStringData) } catch { return AttributedString("Failed to decode AttributedString: \(error)") } } set { do { self.attributedStringData = try JSONEncoder().encode(newValue) } catch { print("Failed to encode AttributedString: \(error)") } } } ../.. Computed attributedString is used in a TextEditor private var textEditorView: some View { Section { TextEditor(text: $model.attributedString) } header: { HStack { Text("TextEditor".localizedUppercase) .foregroundStyle(.secondary) Spacer() } } } Plain Text encode, decode and sync like a charm through iOS and macOS Use of "FontAttributes" (Bold, Italic, …) works the same But use of "ForegroundColorAttributes" trigger an error : Failed to decode AttributedString: dataCorrupted(Swift.DecodingError.Context(codingPath: [_CodingKey(stringValue: "Index 3", intValue: 3), AttributeKey(stringValue: "SwiftUI.ForegroundColor", intValue: nil), CodableBoxCodingKeys(stringValue: "value", intValue: 1)], debugDescription: "Platform color is not available on this platform", underlyingError: nil)) Is there a way to encode/decode attributedString data platform conditionally ? Or another approach ? Thanks for advices

Hi, I am implementing a premium feature in my app where CloudKit syncing is available only for "Pro" users. The Workflow: Free Users: I initialize the ModelContainer with cloudKitDatabase: .none so their data stays local. Pro Upgrade: When a user purchases a subscription, I restart the container with cloudKitDatabase: .automatic to enable syncing. The Problem: If a user starts as "Free" (creates local data) and later upgrades to "Pro", the app crashes immediately upon launch with the following error: Fatal error: Failed to create ModelContainer: SwiftDataError(_error: SwiftData.SwiftDataError._Error.loadIssueModelContainer, _explanation: nil) It seems that SwiftData fails to load the existing data once the configuration changes to expect a CloudKit-backed store. My Question: Is there a supported way to "toggle" CloudKit on for an existing local dataset without causing this crash? I want the user's existing local data to start syncing once they pay, but currently, it just crashes. My code: import Foundation import SwiftData public enum DataModelEnum: String { case task, calendar public static let container: ModelContainer = { let isSyncEnabled = UserDefaults.isProUser let config = ModelConfiguration( groupContainer: .identifier("group.com.yourcompany.myApp"), cloudKitDatabase: isSyncEnabled ? .automatic : .none ) do { return try ModelContainer(for: TaskModel.self, CalendarModel.self, configurations: config) } catch { fatalError("Failed to create ModelContainer: \(error)") } }() }

I am using SwiftData with CloudKit to synchronize data across multiple devices, and I have encountered an issue: occasionally, abnormal sync behavior occurs between two devices (it does not happen 100% of the time—only some users have reported this problem). It seems as if synchronization between the two devices completely stops; no matter what operations are performed on one end, the other end shows no response. After investigating, I suspect the issue might be caused by both devices simultaneously modifying the same field, which could lead to CloudKit's logic being unable to handle such conflicts and causing the sync to stall. Are there any methods to avoid or resolve this situation? Of course, I’m not entirely sure if this is the root cause. Has anyone encountered a similar issue?

CloudKit CKRecordZone Deletion Issue Problem: CloudKit record zones deleted via CKDatabase.modifyRecordZones(deleting:) or CKModifyRecordZonesOperation are successfully removed but then reappear. I suspect they are automatically reinstated by CloudKit sync, despite successful deletion confirmation. Environment: SwiftData with CloudKit integration Custom CloudKit zones created for legacy zone-based sharing Observed Behavior: Create custom zone (e.g., "TestZone1") via CKDatabase.modifyRecordZones(saving:) Copy records to zone for sharing purposes Delete zone using any CloudKit deletion API - returns success, no errors Immediate verification: Zone is gone from database.allRecordZones() After SwiftData/CloudKit sync or app restart: Zone reappears Reproduction: Tested with three different deletion methods - all exhibit same behaviour: modifyRecordZones(deleting:) async API CKModifyRecordZonesOperation (fire-and-forget) CKModifyRecordZonesOperation with result callbacks Zone deletion succeeds, change tokens (used to track updates to shared records) cleaned up But zones are restored presumably by CloudKit background sync Expected: Deleted zones should remain deleted Actual: Zones are reinstated, creating orphaned zones

Simple code like struct ContentView: View { @Query var items: [Item] var body: some View { VStack { Image(systemName: "globe") .imageScale(.large) .foregroundStyle(.tint) Text("Hello, world!") } .padding() } } causes UI Hierarchy crash, on Simulators, iPhone and Mac I found no solution but use @State with fetch descriptor.

Trying to support undo & redo in an app that utilizes Swift Data and as with anything other than provided simplistic Apple demo examples the experience is not great. The problem: Im trying to build functionality that allows users to add items to an item group, where item and item group have a many-to-many relationship e.g. item group can hold many items and items can appear in multiple groups. When trying to do so with relatively simple setup of either adding or removing item group from items relationship array, I am pretty consistently met with a hard crash after performing undo & redo. Sometimes it works the first few undo & redos but 95% of the time would crash on the first one. Could not cast value of type 'Swift.Optional<Any>' (0x20a676be0) to 'Swift.Array<App.CodableStructModel>' (0x207a2bc08). Where CodableStructModel is a Codable Value type inside Item. Adding and removing this relationship should be undoable & redoable as typical for Mac interaction and is "supported" by SwiftData by default, meaning that the developer has to actively either wholly opt out of undo support in their modelContainer setup or do it on a per action scale with the only thing I know of: modelContext.processPendingChanges() modelContext.undoManager?.disableUndoRegistration() ..... modelContext.processPendingChanges() modelContext.undoManager?.enableUndoRegistration() General rant on SwiftData: Random crashes, inconsistencies, random cryptic errors thrown by the debugger and general lack of production level stability. Each update breaks something new and there is very little guidance and communication from the Swift Data team on how to adapt and more importantly consideration for developers that have adopted Swift Data. If SwiftData is not ready for production, it would go a long way to clearly communicate that and mark it as Beta product.

Greetings my fellow engineers, I use SwiftData in my iOS app. The schema is unversioned and consists of a single model. I've been modifying the model for almost two years now and relying on automatic database migrations. I had no problems for all that time, but now trying to add a property to the model or even remove a property from the model results in an error which seems like SwiftData is no longer capable of performing an automatic migration. The log console has things like the following: CoreData: error: NSUnderlyingError : Error Domain=NSCocoaErrorDomain Code=134190 "(null)" UserInfo={reason=Each property must have a unique renaming identifier} CoreData: error: reason : Can't find or automatically infer mapping model for migration CoreData: error: storeType: SQLite CoreData: error: configuration: default CoreData: annotation: options: CoreData: annotation: NSMigratePersistentStoresAutomaticallyOption : 1 CoreData: annotation: NSInferMappingModelAutomaticallyOption : 1 CoreData: annotation: NSPersistentStoreRemoteChangeNotificationOptionKey : 1 CoreData: annotation: NSPersistentHistoryTrackingKey : 1 CoreData: error: <NSPersistentStoreCoordinator: 0x7547b5480>: Attempting recovery from error encountered during addPersistentStore: 0x753f8d800 Error Domain=NSCocoaErrorDomain Code=134140 "Persistent store migration failed, missing mapping model." Have you ever encountered such an issue? What are my options?