I have an iOS app (1Address) which allows users to share their address with family and friends using CloudKit Sharing. Users share their address record (CKRecord) via a share link/url which when tapped allows the receiving user to accept the share and have a persistent view into the sharing user's address record (CKShare). However, most users when they recieve a sharing link do not have the app installed yet, and so when a new receiving user taps the share link, it prompts them to download the app from the app store. After the new user downloads the app from the app store and opens the app, my understanding is that the system (iOS) will/should then vend to my app the previously tapped cloudKitShareMetadata (or share url), however, this metadata is not being vended by the system. This forces the user to re-tap the share link and leads to some users thinking the app doesn't work or not completing the sharing / onboarding flow. Is there a workaround or solve for this that doesn't require the user to tap the share link a second time? In my scene delegate I am implementing: func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {...} And also func scene(_ scene: UIScene, continue userActivity: NSUserActivity) {...} And also: func windowScene(_ windowScene: UIWindowScene, userDidAcceptCloudKitShareWith cloudKitShareMetadata: CKShare.Metadata) {...} And: func scene(_ scene: UIScene, openURLContexts URLContexts: Set<UIOpenURLContext>) {...} Unfortunately, none of these are called or passed metadata on the initial app run after install. Only after the user goes back and taps a link again can they accept the share. This documentation: https://aninterestingwebsite.com/documentation/cloudkit/ckshare says that adding the CKSharingSupported key to your app's Info.plist file allows the system to launch your app when a user taps or clicks a share URL, but it does not clarify what should happen if your app is being installed for the first time. This seems to imply that the system is holding onto the share metadata and/or url, but for some reason it is not being vended to the app on first run. Open to any ideas here for how to fix and I also filed feedback: FB20934189.

If use a SortDescriptor for a model and sort by some attribute from a relationship, in DEBUG mode it all works fine and sorts. However, in release mode, it is an instant crash. SortDescriptor(.name, order: .reverse) ---- works SortDescriptor(.assignedUser?.name, order: .reverse) ---- works in debug but crash in release. What is the issue here, is it that SwiftData just incompetent to do this?

I encountered an error when trying to rollback context after deleting some model with multiple one-to-many relationships when encountered a problem later in a deleting method and before saving the changes. Something like this: do { // Fetch model modelContext.delete(model) // Do some async work that potentially throws try modelContext.save() } catch { modelContext.rollback() } When relationship is empty - the parent has no children - I can safely delete and rollback with no issues. However, when there is even one child when I call even this code: modelContext.delete(someModel) modelContext.rollback() I'm getting a fatal error: SwiftData/ModelSnapshot.swift:46: Fatal error: Unexpected backing data for snapshot creation: SwiftData._FullFutureBackingData<ChildModel> I use ModelContext from within the ModelActor but using mainContext changes nothing. My ModelContainer is quite simple and problem occurs on both in-memory and persistent storage, with or without CloudKit database being enabled. I can isolate the issue in test environment, so the model that's being deleted (or any other) is not being accessed by any other part of the application. However, problem looks the same in the real app. I also changed the target version of iOS from 18.0 to 26.0, but to no avail. My models look kind of like this: @Model final class ParentModel { var name: String @Relationship(deleteRule: .cascade, inverse: \ChildModel.parent) var children: [ChildModel]? init(name: String) { self.name = name } } @Model final class ChildModel { var name: String @Relationship(deleteRule: .nullify) var parent: ParentModel? init(name: String) { self.name = name } } I tried many approaches that didn't help: Fetching all children (via fetch) just to "populate" the context Accessing all children on parent model (via let _ = parentModel.children?.count) Deleting all children reading models from parent: for child in parentModel.children ?? [] { modelContext.delete(child) } Deleting all children like this: let parentPersistentModelID = parentModel.persistentModelID modelContext.delete(model: ChildModel.self, where: #Predicate { $0.parent.persistentModelID == parentPersistentModelID }, includeSubclasses: true) Removing @Relationship(deleteRule: .nullify) from ChildModel relationship definition I found 2 solution for the problem: To manually fetch and delete all children prior to deleting parent: let parentPersistentModelID = parentModel.persistentModelID for child in try modelContext.fetch(FetchDescriptor<ChildModel>(predicate: #Predicate { $0.parent.persistentModelID == parentPersistentModelID })) { modelContext.delete(child) } modelContext.delete(parentModel) Trying to run my code in child context (let childContext = ModelContext(modelContext.container)) All that sounds to me like a problem deep inside Swift Data itself. The first solution I found, fetching potentially hundreds of child models just to delete them in case I might need to rollback changes on some error, sounds like awful waste of resources to me. The second one however seems to work fine has that drawback that I can't fully test my code. Right now I can wrap the context (literally creating class that holds ModelContext and calls its methods) and in tests for throwing methods force them to throw. By creating scratch ModelContext I loose that possibility. What might be the real issue here? Am I missing something?

Hi All, I work on a cross platform app, iOS/macOS. All devises on iOS could synchronize data from Coredata : I create a client, I see him an all iOS devices. But when I test on macOs (with TestFlight) the Mac app could not get any information from iOs devices. On Mac, cloud drive is working because I could download and upload documents and share it between all devices, so the account is working but with my App on MacOS, there is no synchronisation. idea????

I am following Apple's instruction to sync SwiftData with CloudKit. While initiating the ModelContainer, right after removing the store from Core Data, the error occurs: FAULT: NSInternalInconsistencyException: This NSPersistentStoreCoordinator has no persistent stores (unknown). It cannot perform a save operation.; (user info absent) I've tried removing default.store and its related files/folders before creating the ModelContainer with FileManager but it does not resolve the issue. Isn't it supposed to create a new store when the ModelContainer is initialized? I don't understand why this error occurs. Error disappears when I comment out the #if DEBUG block. Code: import CoreData import SwiftData import SwiftUI struct InitView: View { @Binding var modelContainer: ModelContainer? @Binding var isReady: Bool @State private var loadingDots = "" @State private var timer: Timer? var body: some View { VStack(spacing: 16) { Text("Loading\(loadingDots)") .font(.title2) .foregroundColor(.gray) } .padding() .onAppear { startAnimation() registerTransformers() let config = ModelConfiguration() let newContainer: ModelContainer do { #if DEBUG // Use an autorelease pool to make sure Swift deallocates the persistent // container before setting up the SwiftData stack. try autoreleasepool { let desc = NSPersistentStoreDescription(url: config.url) let opts = NSPersistentCloudKitContainerOptions(containerIdentifier: "iCloud.my-container-identifier") desc.cloudKitContainerOptions = opts // Load the store synchronously so it completes before initializing the // CloudKit schema. desc.shouldAddStoreAsynchronously = false if let mom = NSManagedObjectModel.makeManagedObjectModel(for: [Page.self]) { let container = NSPersistentCloudKitContainer(name: "Pages", managedObjectModel: mom) container.persistentStoreDescriptions = [desc] container.loadPersistentStores { _, err in if let err { fatalError(err.localizedDescription) } } // Initialize the CloudKit schema after the store finishes loading. try container.initializeCloudKitSchema() // Remove and unload the store from the persistent container. if let store = container.persistentStoreCoordinator.persistentStores.first { try container.persistentStoreCoordinator.remove(store) } } // let fileManager = FileManager.default // let sqliteURL = config.url // let urls: [URL] = [ // sqliteURL, // sqliteURL.deletingLastPathComponent().appendingPathComponent("default.store-shm"), // sqliteURL.deletingLastPathComponent().appendingPathComponent("default.store-wal"), // sqliteURL.deletingLastPathComponent().appendingPathComponent(".default_SUPPORT"), // sqliteURL.deletingLastPathComponent().appendingPathComponent("default_ckAssets") // ] // for url in urls { // try? fileManager.removeItem(at: url) // } } #endif newContainer = try ModelContainer(for: Page.self, configurations: config) // ERROR!!! } catch { fatalError(error.localizedDescription) } modelContainer = newContainer isReady = true } .onDisappear { stopAnimation() } } private func startAnimation() { timer = Timer.scheduledTimer( withTimeInterval: 0.5, repeats: true ) { _ in updateLoadingDots() } } private func stopAnimation() { timer?.invalidate() timer = nil } private func updateLoadingDots() { if loadingDots.count > 2 { loadingDots = "" } else { loadingDots += "." } } } import CoreData import SwiftData import SwiftUI @main struct MyApp: App { @State private var modelContainer: ModelContainer? @State private var isReady: Bool = false var body: some Scene { WindowGroup { if isReady, let modelContainer = modelContainer { ContentView() .modelContainer(modelContainer) } else { InitView(modelContainer: $modelContainer, isReady: $isReady) } } } }

I have several macOS applications that use CloudKit. I need to test and finds out what happens when the user signs out of their iCloud account. That's because the application may lose data after signing out and then signing in again. Every time I do that, it'll take 15, 20 minutes... I don't time it, but it takes quite a gigantic time to sign out as the spinner keeps rolling. Why does it take so long to just sign out? This sign out effect is untestable because it takes a long time to sign out of an iCloud account and then make changes to the code and then test again. In case you need to know, my system version is Sequoia 15.7.

I currently have a schema in production (cloudKit and local files) containing non-optional transformable values, e.g. @Attribute(.transformable(by: TestTransformer.self)) var number: TestTransformable = TestTransformable.init(value: 100) Unfortunately, this is preventing any migration from succeeding (documented at length in FB22151570). Briefly summarized, any migration from a Schema containing non-optional transformable values fails between willMigrate and didMigrate with the error "Can't find model for source store". This occurs for all migrations, including lightweight with a migration plan, lightweight without a plan, and custom migrations. Worst of all, this also prevents migration to optional transformable values, or the elimination of the transformable value entirely, leaving us completely stuck. (note: optional transformable values only work when they have a default value set to nil, otherwise even these have issues migrating) We already have features being blocked by this issue, and would like to preserve user-data while restoring our ability to move forwards with database. Are there any known workarounds for using SwiftData (+CloudKit) when schema migration is non-operational?

While testing record creation in public CloudKit database for authenticated user I am able to do so without any issues. But for devices missing iCloud account or authentication expired I am seeing the below error: ▿ <CKError 0x97a959200: "Permission Failure" (10/2007); server message = "CREATE operation not permitted"; op = 67331DE3AF3DD666; uuid = 1F3ACD4F-A799-4CD4-ADF0-EDE9E12F2DCB; container ID = "***"> _nsError : <CKError 0x97a959200: "Permission Failure" (10/2007); server message = "CREATE operation not permitted"; op = 67331DE3AF3DD666; uuid = 1F3ACD4F-A799-4CD4-ADF0-EDE9E12F2DCB; container ID = "***"> I am unable to add create/write permission to _world security role in dashboard. Is this something not supported by Cloudkit? Only authenticated iCloud users will be able to create and write data to public database as well?

I have a SwiftData flashcard app which I am syncing with CloudKit using NSPersistentCloudKitContainer. While syncing itself is working perfectly, I have noticed a dramatic increase in the app size after enabling sync. Specifically, without CloudKit, 15k flashcards results in the default.store file being about 4.5 MB. With CloudKit, default.store is about 67 MB. I have inspected the store and found that most of this increase is due to the ANSCKRECORDMETADATA table. My question is, does implementing CloudKit normally cause this magnitude of increase in storage? If it doesn’t, is there something in my model, schema, implementation, etc. that could be causing it? Below are two other posts describing a similar issue, but neither with a solution. I replied to the first one about a month ago. I then submitted this to Developer Technical Support, but was asked to post my question in the forums, so here it is. Strange behavior with 100k+ records in NSPersistentCloudKitContainer Huge increase in sqlite file size after adopting CloudKit

We are trying to solve for the following condition with SwiftData + CloudKit: Lots of data in CloudKit Perform "app-reset" to clear data & App settings and start fresh. Reset data models with try modelContext.delete(model:_) myModel.count() confirms local deletion (0 records); but iCloud Console shows expectedly slow process to delete. Old CloudKit data is returning during the On Boarding process. Questions: • Would making a new iCloud Zone for each reset work around this, as the new zone would be empty? We're having trouble finding details about how to do this with SwiftData. • Would CKSyncEngine have a benefit over the default SwiftData methods? Open to hearing if anyone has experienced a similar challenge and how you worked around it!

Since running on iOS 14b1, I'm getting this in my log (I have Core Data logging enabled): error: Store opened without NSPersistentHistoryTrackingKey but previously had been opened with NSPersistentHistoryTrackingKey - Forcing into Read Only mode store at 'file:///private/var/mobile/Containers/Shared/AppGroup/415B75A6-92C3-45FE-BE13-7D48D35909AF/StoreFile.sqlite' As far as I can tell, it's impossible to open my store without that key set - it's in the init() of my NSPersistentContainer subclass, before anyone calls it to load stores. Any ideas?

I am trying out the new AttributedString binding with SwiftUI’s TextEditor in iOS26. I need to save this to a Core Data database. Core Data has no AttributedString type, so I set the type of the field to “Transformable”, give it a custom class of NSAttributedString, and set the transformer to NSSecureUnarchiveFromData When I try to save, I first convert the Swift AttributedString to NSAttributedString, and then save the context. Unfortunately I get this error when saving the context, and the save isn't persisted: CoreData: error: SQLCore dispatchRequest: exception handling request: <NSSQLSaveChangesRequestContext: 0x600003721140> , <shared NSSecureUnarchiveFromData transformer> threw while encoding a value. with userInfo of (null) Here's the code that tries to save the attributed string: struct AttributedDetailView: View { @ObservedObject var item: Item @State private var notesText = AttributedString() var body: some View { VStack { TextEditor(text: $notesText) .padding() .onChange(of: notesText) { item.attributedString = NSAttributedString(notesText) } } .onAppear { if let nsattributed = item.attributedString { notesText = AttributedString(nsattributed) } else { notesText = "" } } .task { item.attributedString = NSAttributedString(notesText) do { try item.managedObjectContext?.save() } catch { print("core data save error = \(error)") } } } } This is the attribute setup in the Core Data model editor: Is there a workaround for this? I filed FB17943846 if someone can take a look. Thanks.

If I set my build settings "default actor isolation" to MainActor, how do my @ModelActor actors and model classes need to look like ? For now, I am creating instances of my @ModelActor actors and passing my modelContext container and processing all data there. Everything stays in this context. No models are transferred back to MainActor. Now, after changing my project settings, I am getting a huge amount of warnings. Do I need to set all my model classes to non-isolated and the @ModelActor actor as well? Is there any new sample code to cover this topic ... did not find anything for now. Thanks in advance, Marc

Hi everyone, On macOS 26.4 beta (with Xcode 26.4 beta), I’m seeing the following console messages in a brand new SwiftData + CloudKit template project (no custom logic added, fresh CloudKit container): updateTaskRequest called for a pre-running task com.apple.coredata.cloudkit.activity.export.F9EE783D-7521-4EC2-B42C-9FD1F29BA5C4 updateTaskRequest called for an already running/updated task com.apple.coredata.cloudkit.activity.export.F9EE783D-7521-4EC2-B42C-9FD1F29BA5C4 Error updating background task request: Error Domain=BGSystemTaskSchedulerErrorDomain Code=8 "(null)" These messages appear: When CloudKit is enabled Occasionally on app launch Often when bringing the app back to the foreground (Cmd-Tab away and back) Even with zero additional SwiftData logic They do not appear when CloudKit is disabled. This behavior is reproducible on a completely new project with a fresh CloudKit container. Questions: What exactly do these messages indicate? Is BGSystemTaskScheduler Code=8 expected in this context? Are these safe to ignore? Is this a known change in logging behavior in macOS 26.4 beta? Additionally, in a larger project I’ve observed SwiftData crashes and initially suspected these logs might be related. However, since the issue reproduces in a fresh template project, I’m unsure whether this is simply verbose beta logging or something more serious. Any clarification would be appreciated. Filed as FB21993521.

Hi. I'm hoping someone might be able to help us with an issue that's been affecting our standalone watchOS app for some time now. We've encountered consistent crashes on Apple Watch devices when the app enters the background while the device is offline (i.e., no Bluetooth and no Wi-Fi connection). Through extensive testing, we've isolated the problem to the use of NSPersistentCloudKitContainer. When we switch to NSPersistentContainer, the crashes no longer occur. Interestingly, this issue only affects our watchOS app. The same CloudKit-based persistence setup works reliably on our iOS and macOS apps, even when offline. This leads us to believe the issue may be specific to how NSPersistentCloudKitContainer behaves on watchOS when the device is disconnected from the network. We're targeting watchOS 10 and above. We're unsure if this is a misconfiguration on our end or a potential system-level issue, and we would greatly appreciate any insight or guidance.

I'm a first time developer for Swift, (getting on a bit!) but after programming in VB back in the late 90s I wanted to write an app for iPhone. I think I might have gone about it the wrong way, but I've got an app that works great on my iPhone or works great on my iPad. It saves the data persistently on device, but, no matter how much I try, what I read and even resorting to AI (ChatGPT & Gemini) I still can't get it to save the data on iCloud to synchronise between the two and work across the devices. I think it must be something pretty fundamental I'm doing (or more likely not doing) that is causing the issue. I'm setting up my signing and capabilities as per the available instructions but I always get a fatal error. I think it might be something to do with making fields optional, but at this point I'm second guessing myself and feeling a complete failure. Any advice or pointers would be really gratefully appreciated. I like my app and would like eventually to get it on the App Store but at this point in time I feel it should be on the failed projects heap! I've even tried a new Xcode project for iOS and asking it to use SwiftData and CloudKit - the default project should work - right? But it absolutely doesn't for me. Please send help!!

I have the following struct doing some simple tasks, running a network request and then saving items to Core Data. Per Xcode 26's new default settings (onisolated(nonsending) & defaultIsolation set to MainActor), the struct and its functions run on the main actor, which works fine and I can even safely omit the context.perform call because of it, which is great. struct DataHandler { func importGames(withIDs ids: [Int]) async throws { ... let context = PersistenceController.shared.container.viewContext for game in games { let newGame = GYGame(context: context) newGame.id = UUID() } try context.save() } } Now, I want to run this in a background thread to increase performance and responsiveness. So I followed this session (https://aninterestingwebsite.com/videos/play/wwdc2025/270) and believe the solution is to mark the struct as nonisolated and the function itself as @concurrent. The function now works on a background thread, but I receive a crash: _dispatch_assert_queue_fail. This happens whether I wrap the Core Data calls with context.perform or not. Alongside that I get a few new warnings which I have no idea how to work around. So, what am I doing wrong here? What's the correct way to solve this simple use case with Swift 6's new concurrency stuff and the default main actor isolation in Xcode 26? Curiously enough, when setting onisolated(nonsending) to false & defaultIsolation to non isolating, mimicking the previous behavior, the function works without crashing. nonisolated struct DataHandler { @concurrent func importGames(withIDs ids: [Int]) async throws { ... let context = await PersistenceController.shared.container.newBackgroundContext() for game in games { let newGame = GYGame(context: context) newGame.id = UUID() // Main actor-isolated property 'id' can not be mutated from a nonisolated context; this is an error in the Swift 6 language mode } try context.save() } }

Hi, I’m working on a macOS app that includes a file browser component. And I’m trying to match Finder’s behavior for color tags and folder icons. For local files/folders everything works fine: Tag color key returns the expected label number via NSColor * labelColor = nil; [fileURL getResourceValue:&labelColor forKey:NSURLLabelColorKey error:nil]; NSNumber * labelKey = nil; [fileURL getResourceValue:&labelKey forKey:NSURLLabelNumberKey error:nil]; QLThumbnailGenerator obtains the expected colored folder icon (including emoji/symbol overlay if set) via QLThumbnailGenerationRequest * request = [[QLThumbnailGenerationRequest alloc] initWithFileAtURL:fileURL size:iconSize scale:scaleFactor representationTypes:QLThumbnailGenerationRequestRepresentationTypeIcon]; request.iconMode = YES; [[QLThumbnailGenerator sharedGenerator] generateBestRepresentationForRequest:request completionHandler:^(QLThumbnailRepresentation * _Nullable thumbnail, NSError * _Nullable error) { if (thumbnail != nil && error == nil) { NSImage * thumbnailImage = [thumbnail NSImage]; // ... } }]; However, for items on iCloud Drive (whether currently downloaded locally or only stored in the cloud), the same code always produces gray colors, while Finder shows everything correctly: NSURLLabelNumberKey always returns 1 (gray) for items with color tags, and 0 for non-tagged. Folder icons returned via QLThumbnailGenerator are gray, no emoji/symbol overlays. Reading tag data from xattr gives values like “Green\1” (tag name matches, but numeric value is still "Gray"). Also, if I move a correctly-tagged local item into iCloud Drive, it immediately becomes gray in my app (Finder still shows the correct colors). Question: What is the supported way to retrieve Finder tag colors and the correct folder icon appearance (color + overlays) for items in iCloud Drive, so that the result matches Finder? I am on macOS Tahoe 26.2/26.3, Xcode 26.2 (17C52). If you need any additional details, please let me know. Thanks!

Hi everyone, I’m working on an offline-first iOS app using Core Data. I have a question about safe future updates: in my project, I want to be able to add new optional fields to existing Entities or even completely new Entities in future versions — but nothing else (no renaming, deleting, or type changes). Here’s how my current PersistenceController looks: import CoreData struct PersistenceController { static let shared = PersistenceController() let container: NSPersistentContainer init(inMemory: Bool = false) { container = NSPersistentContainer(name: "MyApp") if inMemory { container.persistentStoreDescriptions.first!.url = URL(fileURLWithPath: "/dev/null") } container.loadPersistentStores(completionHandler: { (storeDescription, error) in if let error = error as NSError? { print("Core Data failed to load store: \(error), \(error.userInfo)") } }) container.viewContext.automaticallyMergesChangesFromParent = true } } Do I need to explicitly set these properties to ensure lightweight migration works? shouldMigrateStoreAutomatically = true shouldInferMappingModelAutomatically = true Or, according to the documentation, are they already true by default, so I can safely add optional fields and new Entities in future versions without breaking users’ existing data? Thanks in advance for your guidance!

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?