Hi, I am experiencing main thread freezes from fetching on Main Actor. Attempting to move the function to a background thread, but whenever I reference the TestModel in a nonisolated context or in another model actor, I get this warning: Main actor-isolated conformance of 'TestModel' to 'PersistentModel' cannot be used in actor-isolated context; this is an error in the Swift 6 language mode Is there a way to do this correctly? Recreation, warning on line 13: class TestModel { var property: Bool = true init() {} } struct SendableTestModel: Sendable { let property: Bool } @ModelActor actor BackgroundActor { func fetch() throws -> [SendableTestModel] { try modelContext.fetch(FetchDescriptor<TestModel>()).map { SendableTestModel(property: $0.property) } } }

My app uses iCloud to let users sync their files via their private iCloud Drive, which does not use CloudKit. FileManager.default.url(forUbiquityContainerIdentifier: nil)?.appending(component: "Documents") I plan to transfer my app to another developer account, but I'm afraid it will affect the access of the app to the existing files in that folder. Apple documentation doesn't mention this case. Has anyone done this before and can confirm if the app will continue to work normally after transferring? Thanks

I built a SwiftData App that relies on CloudKit to synchronize data across devices. That means all model relationships must be expressed as Optional. That’s fine, but there is a limitation in using Optional’s in SwiftData SortDescriptors (Crashes App) That means I can’t apply a SortDescriptor to ModelA using some property value in ModelB (even if ModelB must exist) I tried using a computed property in ModelA that referred to the property in ModelB, BUT THIS DOESN”T WORK EITHER! Am I stuck storing redundant data In ModelA just to sort ModelA as I would like???

Testing Environment: iOS 18.4.1 / macOS 15.4.1 I am working on an iOS project that aims to utilize the user's iCloud Drive documents directory to save a specific directory-based file structure. Essentially, the app would create a root directory where the user chooses in iCloud Drive, then it would populate user generated files in various levels of nested directories. I have been attempting to use NSMetadataQuery with various predicates and search scopes but haven't been able to get it to directly monitor changes to files or directories that are not in the root directory. Instead, it only monitors files or directories in the root directory, and any changes in a subdirectory are considered an update to the direct children of the root directory. Example iCloud Drive Documents (Not app's ubiquity container) User Created Root Directory (Being monitored) File A Directory A File B An insertion or deletion within Directory A would only return a notification with userInfo containing data for NSMetadataQueryUpdateChangedItemsKey relating to Directory A, and not the file or directory itself that was inserted or deleted. (Query results array also only contain the direct children.) I have tried all combinations of these search scopes and predicates with no luck: query.searchScopes = [ rootDirectoryURL, NSMetadataQueryUbiquitousDocumentsScope, NSMetadataQueryAccessibleUbiquitousExternalDocumentsScope, ] NSPredicate(value: true) NSPredicate(format: "%K LIKE '*.md'", NSMetadataItemFSNameKey) NSPredicate(format: "%K BEGINSWITH %@", NSMetadataItemPathKey, url.path(percentEncoded: false)) I do see these warnings in the console upon starting my query: [CRIT] UNREACHABLE: failed to get container URL for com.apple.CloudDocs [ERROR] couldn't fetch remote operation IDs: NSError: Cocoa 257 "The file couldn’t be opened because you don’t have permission to view it." "Error returned from daemon: Error Domain=com.apple.accounts Code=7 "(null)"" But I am not sure what to make of that, since it does act normally for finding updates in the root directory. Hopefully this isn't a limitation of the API, as the only alternative I could think of would be to have multiple queries running for each nested directory that I needed updates for.

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://developer.apple.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 having trouble implementing iCloud Drive in my app. I've already taken the obvious steps, including enabling iCloud Documents in Xcode and selecting a container. This container is correctly specified in my code, and in theory, everything should work. The data generated by my app should be saved to iCloud Drive in addition to local storage. The data does get stored in the Files app, but the automatic syncing to iCloud Drive doesn’t work as expected. I’ve also considered updating my .entitlements file. Since I’m at a loss, I’m reaching out for help maybe I’ve overlooked something important that's causing it not to work. If anyone has an idea, please let me know. Thanks in advance!

Description: I'm experiencing a critical issue with SwiftData custom migrations where objects created during migration appear to be inserted successfully but aren't persisted or found by queries after migration completes. The migration logs show objects being created, but subsequent queries return zero results. Problem Details: I'm migrating from schema version V2 to V3, which involves: Renaming Person class to GroupData Keeping the same data structure but changing the class name Using a custom migration stage to copy data from old to new schema Migration Code: swift static let migrationV2toV3 = MigrationStage.custom( fromVersion: LinkMapV2.self, toVersion: LinkMapV3.self, willMigrate: { context in do { let persons = try context.fetch(FetchDescriptor<LinkMapV2.Person>()) print("Found (persons.count) Person objects to migrate") // ✅ Shows 11 objects for person in persons { let newGroup = LinkMapV3.GroupData( id: person.id, // Same UUID name: person.name, // ... other properties ) context.insert(newGroup) print("Inserted GroupData: '\(newGroup.name)'") // ✅ Confirms insertion } try context.save() // ✅ No error thrown print("Successfully migrated \(persons.count) objects") // ✅ Confirms save } catch { print("Migration error: \(error)") } }, didMigrate: { context in do { let groups = try context.fetch(FetchDescriptor<LinkMapV3.GroupData>()) print("Final GroupData count: \(groups.count)") // ❌ Shows 0 objects! } catch { print("Verification error: \(error)") } } ) Console Output: text === MIGRATION STARTED === Found 11 Person objects to migrate Migrating Person: 'Riverside of pipewall' with ID: 7A08C633-4467-4F52-AF0B-579545BA88D0 Inserted new GroupData: 'Riverside of pipewall' ... (all 11 objects processed) ... === MIGRATION COMPLETED === Successfully migrated 11 Person objects to GroupData === MIGRATION VERIFICATION === New GroupData count: 0 // ❌ PROBLEM: No objects found! What I've Tried: Multiple context approaches: Using the provided migration context Creating a new background context with ModelContext(context.container) Using context.performAndWait for thread safety Different save strategies: Calling try context.save() after insertions Letting SwiftData handle saving automatically Multiple save calls at different points Verification methods: Checking in didMigrate closure Checking in app's ContentView after migration completes Using both @Query and manual FetchDescriptor Schema variations: Direct V2→V3 migration Intermediate V2.5 schema with both classes Lightweight migration with @Attribute(originalName:) Current Behavior: Migration runs without errors Objects appear to be inserted successfully context.save() completes without throwing errors But queries in didMigrate and post-migration return empty results The objects seem to exist in a temporary state that doesn't persist Expected Behavior: Objects created during migration should be persisted and queryable Post-migration queries should return the migrated objects Data should be available in the main app after migration completes Environment: Xcode 16.0+ iOS 18.0+ SwiftData Swift 6.0+ Key Questions: Is there a specific way migration contexts should be handled for data to persist? Are there known issues with object persistence in custom migrations? Should we be using a different approach for class renaming migrations? Is there a way to verify that objects are actually being written to the persistent store? The migration appears to work perfectly until the verification step, where all created objects seem to vanish. Any guidance would be greatly appreciated! Additional Context from my investigation: I've noticed these warning messages during migration that might be relevant: text SwiftData.ModelContext: Unbinding from the main queue. This context was instantiated on the main queue but is being used off it. error: Persistent History (76) has to be truncated due to the following entities being removed: (Person) This suggests there might be threading or context lifecycle issues affecting persistence. Let me know if you need any additional information about my setup or migration configuration!

I'm implementing SwiftData with inheritance in an app. I have an Entity class with a property name. This class is inherited by two other classes: Store and Person. The Entity model has a one-to-many relationship with a Transaction class. I can list all my Entity models in a List with a @Query annotation without a problem. However, then I try to access the name property of an Entity from a Transaction relationship, the app crashes with the following error: Thread 1: Fatal error: Never access a full future backing data - PersistentIdentifier(id: SwiftData.PersistentIdentifier.ID(backing: SwiftData.PersistentIdentifier.PersistentIdentifierBacking.managedObjectID(0x96530ce28d41eb63 <x-coredata://DABFF7BB-C412-474E-AD50-A1F30AC6DBE9/Person/p4>))) with Optional(F07E7E23-F8F0-4CC0-B282-270B5EDDC7F3) From my attempts to fix the issue, I noticed that: The crash seems related to the relationships with classes that has inherit from another class, since it only happens there. When I create new data, I can usually access it without any problem. The crash mostly happens after reloading the app. This error has been mentioned on the forum (for example here), but in a context not related with inheritance. You can find the full code here. For reference, my models looks like this: @Model class Transaction { @Attribute(.unique) var id: String var name: String var date: Date var amount: Double var entity: Entity? var store: Store? { entity as? Store } var person: Person? { entity as? Person } init( id: String = UUID().uuidString, name: String, amount: Double, date: Date = .now, entity: Entity? = nil, ) { self.id = id self.name = name self.amount = amount self.date = date self.entity = entity } } @Model class Entity: Identifiable { @Attribute(.preserveValueOnDeletion) var name: String var lastUsedAt: Date @Relationship(deleteRule: .cascade, inverse: \Transaction.entity) var operations: [Transaction] init( name: String, lastUsedAt: Date = .now, operations: [Transaction] = [], ) { self.name = name self.lastUsedAt = lastUsedAt self.operations = operations } } @available(iOS 26, *) @Model class Store: Entity { @Attribute(.unique) var id: String var locations: [Location] init( id: String = UUID().uuidString, name: String, lastUsedAt: Date = .now, locations: [Location] = [], operations: [Transaction] = [] ) { self.locations = locations self.id = id super.init(name: name, lastUsedAt: lastUsedAt, operations: operations) } } In order to reproduce the error: Run the app in the simulator. Click the + button to create a new transaction. Relaunch the app, then click on any transaction. The app crashes when it tries to read te name property while building the details view.

Hi, I'm implementing iCloud backup functionality in my web application using CloudKit JS, but I'm running into some issues. I'd appreciate any help you can provide. Issue: The iCloud backup feature isn't working properly in our web app. I believe I've correctly set up the Apple Developer Program registration and API token generation. While a demo implementation works perfectly with iCloud backup, our app implementation is failing. Specifically: "Sign in with Apple" succeeds However, ck.getDefaultContainer().setupAuth() returns null In the working demo, setupAuth() returns a proper value Even after logging in through the redirect URL provided in the "421 Misdirected Request" error response and executing setupAuth(), it still returns null I've essentially copied the working demo code directly, so I suspect the issue might be related to token generation, permissions, or account configuration. Questions: Could you provide detailed step-by-step instructions for implementing iCloud backup in a web application? I've noticed there are configuration items in the Developer Console and Certificates console, so I may have missed something in one of these areas. Based on the symptoms described, what are the possible causes for setupAuth() returning null in CloudKit JS? Could configuration issues be indirectly causing this, or is it more likely a timing issue or SDK coding problem? Specifically regarding the 421 error and redirect flow - is there something in the configuration that could cause setupAuth() to return null even after successful authentication through the redirect? Thanks in advance for your help!

Hi all, In my SwiftUI / SwiftData / Cloudkit app which is a series of lists, I have a model object called Project which contains an array of model objects called subprojects: final class Project1 { var name: String = "" @Relationship(deleteRule: .cascade, inverse: \Subproject.project) var subprojects : [Subproject]? init(name: String) { self.name = name self.subprojects = [] } } The user will select a project from a list, which will generate a list of subprojects in another list, and if they select a subproject, it will generate a list categories and if the user selects a category it will generate another list of child objects owned by category and on and on. This is the pattern in my app, I'm constantly passing arrays of model objects that are the children of other model objects throughout the program, and I need the user to be able to add and remove things from them. My initial approach was to pass these arrays as bindings so that I'd be able to mutate them. This worked for the most part but there were two problems: it was a lot of custom binding code and when I had to unwrap these bindings using init?(_ base: Binding<Value?>), my program would crash if one of these arrays became nil (it's some weird quirk of that init that I don't understand at al). As I'm still learning the framework, I had not realized that the @model macro had automatically made my model objects observable, so I decided to remove the bindings and simply pass the arrays by reference, and while it seems these references will carry the most up to date version of the array, you cannot mutate them unless you have access to the parent and mutate it like such: project.subcategories?.removeAll { $0 == subcategory } project.subcategories?.append(subcategory) This is weirding me out because you can't unwrap subcategories before you try to mutate the array, it has to be done like above. In my code, I like to unwrap all optionals at the moment that I need the values stored in them and if not, I like to post an error to the user. Isn't that the point of optionals? So I don't understand why it's like this and ultimately am wondering if I'm using the correct design pattern for what I'm trying to accomplish or if I'm missing something? Any input would be much appreciated! Also, I do have a small MRE project if the explanation above wasn't clear enough, but I was unable to paste in here (too long), attach the zip or paste a link to Google Drive. Open to sharing it if anyone can tell me the best way to do so. Thanks!

I have a document based SwiftData app in which I would like to implement a persistent cache. For obvious reasons, I would not like to store the contents of the cache in the documents themselves, but in my app's data directory. Is a use case, in which a document based SwiftData app uses not only the ModelContainers from the currently open files, but also a ModelContainer writing a database file in the app's documents directory (for cache, settings, etc.) supported? If yes, how can you inject two different ModelContexts, one tied to the currently open file and one tied to the local database, into a SwiftUI view?

Hi, I'm trying to sign in with Apple CloudKit. I'm using the following code: 'use client'; import { CLOUDKIT_CONSTANTS } from '@/constants/cloudkit'; import { setCloudKitConfigured } from '@/lib/cloudkitSingleton'; import { CloudKitStatic } from '@/types/cloudkit'; import Script from 'next/script'; declare global { interface Window { CloudKit: CloudKitStatic; } } export default function Home() { const initializeCloudKit = async () =&gt; { console.info('⭐️ initializeCloudKit - start'); // 古い認証情報を削除 try { // LocalStorageから古い認証情報を削除 const keysToRemove = []; for (let i = 0; i &lt; localStorage.length; i++) { const key = localStorage.key(i); if (key &amp;&amp; (key.includes('cloudkit') || key.includes('CloudKit'))) { keysToRemove.push(key); } } keysToRemove.forEach(key =&gt; localStorage.removeItem(key)); // SessionStorageからも削除 const sessionKeysToRemove = []; for (let i = 0; i &lt; sessionStorage.length; i++) { const key = sessionStorage.key(i); if (key &amp;&amp; (key.includes('cloudkit') || key.includes('CloudKit'))) { sessionKeysToRemove.push(key); } } sessionKeysToRemove.forEach(key =&gt; sessionStorage.removeItem(key)); console.log('古い認証情報を削除しました'); } catch (cleanupError) { console.warn('認証情報のクリーンアップ中にエラー:', cleanupError); } try { const cloudKit = window.CloudKit.configure({ containers: [ { containerIdentifier: 'XXXXXX', apiTokenAuth: { apiToken: 'XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX', persist: false, signInButton: { id: 'cloudkit-sign-in-button', theme: 'black', }, signOutButton: { id: 'cloudkit-sign-out-button', theme: 'black', }, }, environment: 'development', }, ], }); console.info('⭐️ cloudKit', cloudKit); setCloudKitConfigured(true); const container = cloudKit.getDefaultContainer(); console.info('⭐️ CloudKit configured, setting up auth...'); // 初期認証状態をチェック try { const initialUser = await container.setUpAuth(); console.info('⭐️ setUpAuth result:', initialUser); } catch (authError) { console.info('⭐️ setUpAuth error (expected for unauthenticated):', authError); } // CloudKitの標準コールバックも併用（念のため） try { container.whenUserSignsIn().then((userInfo: any) =&gt; { console.info('⭐️ CALLBACK: whenUserSignsIn fired!', userInfo); }); container.whenUserSignsOut().then(() =&gt; { console.info('⭐️ CALLBACK: whenUserSignsOut fired!'); }); } catch (callbackError) { console.info('⭐️ Callback setup error (non-critical):', callbackError); } console.info('⭐️ initializeCloudKit - completed'); } catch (error) { console.error('⭐️ Critical CloudKit initialization error:', error); } }; return ( &lt;&gt; &lt;Script src="https://cdn.apple-cloudkit.com/ck/2/cloudkit.js" strategy="afterInteractive" onLoad={() =&gt; { initializeCloudKit(); }} onError={error =&gt; { console.error('⭐️ CloudKit initialization error:', error); }} /&gt; &lt;div id="cloudkit-sign-in-button" /&gt; &lt;div id="cloudkit-sign-out-button" /&gt; &lt;/&gt; ); } In Chrome secret tab, I can sign in successfully. But in Chrome normal tab, I can't sign in. In normal tab, following error occurs on sign in button click: cloudkit.js:14 Uncaught (in promise) Error: UNKNOWN_ERROR cloudkit.js:14 GET https://api.apple-cloudkit.com/database/1/XXXXXX/XXXXXX/public/users/caller?ckjsBuildVersion=2420ProjectDev22&amp;ckjsVersion=2.6.4&amp;clientId=XXXXX-XXXXXXX-XXXX-XXXXX&amp; ckAPIToken=XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XXXX 421 (Misdirected Request) I think, cloudkit instance has re-initialized when I click the sign in button only in normal tab. So I can't sign in. Do you have any idea what might be causing the error ? Thanks in advance for your help!

Hi everyone, I am experiencing an iCloud provisioning problem I cannot resolve, and Developer Support has not been able to help. My App ID: com.exaqservices.ArkyvTiles Symptoms: 1. In Xcode (v16.2), enabling iCloud in Signing & Capabilities repeatedly fails with: The app ID does not include the iCloud container. Click Try Again. Clicking Try Again does nothing. The error persists forever. 2. In Certificates, Identifiers & Profiles: • The iCloud capability is enabled for this App ID. • The CloudKit container is selected. • But the portal no longer shows the “iCloud Documents” checkbox, which used to be required for ubiquitous document support. 3. Xcode cannot regenerate provisioning profiles because it claims the App ID is missing the iCloud container — even though the container is attached. 4. Provisioning profiles on the Apple Developer site all appear expired, and new ones do not generate correctly. 5. The App Store Connect interface also does not show an iCloud Services section under App Information → Capabilities as older guides describe. Expected Behavior: Since iCloud and the CloudKit container are enabled on the App ID, Xcode should successfully enable: • com.apple.developer.icloud-services • com.apple.developer.icloud-container-identifiers • com.apple.developer.ubiquity-container-identifiers (if needed) • com.apple.developer.ubiquity-kvstore-identifier Instead, the entitlements never propagate. What I suspect: This seems like an App ID metadata mismatch or a stale backend entry where: • the CloudKit container is attached but the entitlement isn’t linked, • the “iCloud Documents” flag is missing due to a UI transition, • provisioning profiles cannot be regenerated because the App ID is not updating correctly. What I need help with: Can someone from Apple engineering confirm: • Whether my App ID metadata is corrupted, • If entitlements need to be manually refreshed, • Or if the “iCloud Documents” toggle has moved or is no longer exposed? This is blocking development completely — I cannot build, sign, or deploy the app with iCloud. Thank you! Alan Metzger

Is there a way to view the data saved when using swiftdata? Even after deleting all models, the storage space taken up by the app in Settings is too large.

Hello, I'm trying to work on an iPadOS and macOS app that will rely on the document-based system to create some kind of orientation task to follow. Let say task1.myfile will be a check point regulation from NYC to SF and task2.myfile will be a visit as many key location as you can in SF. The file represent the specific landmark location and rules of the game. And once open, I will be able to read KML/GPS file to evaluate their score based with the current task. But opened GPS files does not have to be stored in the task file itself, it stay alongside. I wanted to use that scenario to experiment with SwiftData (I'm a long time CoreData user, I even wrote my own WebDAV based persistent store back in the day), and so, mix both on file and in memory persistent store, with distribution based on object class. With CoreData it would have been possible, but I do not see how to achieve that with SwiftData and DocumentGroup integration. Any idea how to do that?

Overview I'm developing a document-based app for macOS using SwiftData. When I undo/redo changes using Command-Z/Command-Shift-Z, the app reliably crashes with the following error: SwiftData/ModelSnapshot.swift:46: Fatal error: Unexpected backing data for snapshot creation: SwiftData._FullFutureBackingData<DocumentTest.ChildItem> And before the app crashes, what always happens is that UndoManager stops removing/restoring instances of ChildItem (but continues to remove/restore instances of ParentItem). The issue goes away when I enclose the relevant code in ModelContext.transaction(block:). However, this shouldn't be necessary, as ModelContext.autosaveEnabled is true by default. The issues are occurring with Xcode 26.4 (17E192) and macOS Tahoe 26.4 (25E246). I have modified the macOS Document App project template to showcase the issue. The sample project, along with a screen recording of the crash, can be downloaded from here: https://drive.google.com/drive/folders/13bCB1qRZ6273BI81zW2zUUBraSvv6p5w?usp=share_link Is this expected behavior or should I file a bug report in Feedback Assistant? Steps to Reproduce To recreate the issue, follow these steps: Download and extract the "Xcode Project.zip" file linked above. Open the extracted "DocumentTest" project in Xcode. Build and run the "DocumentTest" app. In the document selection window, click "New Document" at the bottom-left. In the app, click the "+" button at the top-right to add a ParentItem with ChildItems. Click on the added ParentItem's button to add another ChildItem to it. Repeat steps 5–6 until you have 5 ParentItems with an additional ChildItem. Press Command-Z 10 times to undo all the changes. Press Command-Shift-Z 10 times to redo all the changes. Repeat steps 8–9 until UndoManager stops removing/restoring the additional ChildItem, and continue repeating them until the app eventually crashes (you may have to repeat them 5–10 times before the issue occurs). If you uncomment the ModelContext.transaction(block:) at line 13 of ContentView.swift and repeat the same steps above, no ChildItems will go missing and the app will not crash. Code ParentItem Model @Model final class ParentItem { var timestamp: Date @Relationship( deleteRule: .cascade, inverse: \ChildItem.parentItem ) var childItems: [ChildItem] = [] init(timestamp: Date) { self.timestamp = timestamp } } ChildItem Model @Model final class ChildItem { var index: Int var parentItem: ParentItem? init(index: Int) { self.index = index } } Creating, Inserting, and Linking ParentItem and ChildItem // Create and insert ParentItem let newParentItem = ParentItem( timestamp: Date() ) modelContext.insert(newParentItem) // Create and insert ChildItems var newChildItems: [ChildItem] = [] for index in 0..<Int.random(in: 2...8) { let newChildItem = ChildItem(index: index) newChildItems.append(newChildItem) modelContext.insert(newChildItem) } /* Establish relationship between ParentItem and ChildItems */ for newChildItem in newChildItems { newParentItem.childItems.append( newChildItem ) newChildItem.parentItem = newParentItem } Adding an Additional ChildItem to ParentItem // Uncommenting this block fixes the crash // try! modelContext.transaction { // Create and insert the new ChildItem let newChildItem = ChildItem( index: parentItem.childItems.count ) modelContext.insert(newChildItem) // Establish relationship to parentItem parentItem.childItems.append(newChildItem) newChildItem.parentItem = parentItem // }

I have started from here: Apple's guide on the sharing core data objects between iCloud users and I have created a sample project that has Collections and Items. Everything works great while I stay on Swift 5, like with the initial project. I would like to migrate to Swift 6 (Default Actor Isolaton @MainActor, Approachable Concurrency: Yes) on the project and I am stuck at extension CDCollection: Transferable { ... }. When compiling with Swift 5, there is a warning: Conformance of 'NSManagedObject' to 'Sendable' is unavailable in iOS; this is an error in the Swift 6 language mode. After resolving almost all compile-time warnings I'm left with: Conformance of 'CDCollection' to protocol 'Transferable' crosses into main actor-isolated code and can cause data races. Which I don't think will work, because of the warning shown above. It can be worked around like: nonisolated extension CDCollection: Transferable, @unchecked Sendable Then there are errors: let persistentContainer = PersistenceController.shared.persistentContainer Main actor-isolated static property 'shared' can not be referenced from a nonisolated context. I've created the following class to have a Sendable object: struct CDCollectionTransferable: Transferable { var objectID: NSManagedObjectID var persistentContainer: NSPersistentCloudKitContainer public static var transferRepresentation: some TransferRepresentation { CKShareTransferRepresentation { collectionToExport in let persistentContainer = collectionToExport.persistentContainer let ckContainer = CloudKitProvider.container var collectionShare: CKShare? if let shareSet = try? persistentContainer.fetchShares( matching: [collectionToExport.objectID]), let (_, share) = shareSet.first { collectionShare = share } /** Return the existing share if the collection already has a share. */ if let share = collectionShare { return .existing(share, container: ckContainer) } /** Otherwise, create a new share for the collection and return it. Use uriRepresentation of the object in the Sendable closure. */ let collectionURI = collectionToExport.objectID .uriRepresentation() return .prepareShare(container: ckContainer) { let collection = await persistentContainer.viewContext .perform { let coordinator = persistentContainer.viewContext .persistentStoreCoordinator guard let objectID = coordinator?.managedObjectID( forURIRepresentation: collectionURI ) else { fatalError( "Failed to return the managed objectID for: \(collectionURI)." ) } return persistentContainer.viewContext.object( with: objectID ) } let (_, share, _) = try await persistentContainer.share( [collection], to: nil ) return share } } } } And I'm able to compile and run the app with this change: let transferable = CDCollectionTransferable( objectID: collection.objectID, persistentContainer: PersistenceController.shared .persistentContainer ) ToolbarItem { ShareLink( item: transferable, preview: SharePreview("Share \(collection.name)!") ) { MenuButtonLabel( title: "New Share", systemImage: "square.and.arrow.up" ) } } The app crashes when launched with libdispatch.dylib`_dispatch_assert_queue_fail: 0x1052c6ea4 <+0>: sub sp, sp, #0x50 0x1052c6ea8 <+4>: stp x20, x19, [sp, #0x30] 0x1052c6eac <+8>: stp x29, x30, [sp, #0x40] 0x1052c6eb0 <+12>: add x29, sp, #0x40 0x1052c6eb4 <+16>: adrp x8, 63 0x1052c6eb8 <+20>: add x8, x8, #0xa0c ; "not " 0x1052c6ebc <+24>: adrp x9, 62 0x1052c6ec0 <+28>: add x9, x9, #0x1e5 ; "" 0x1052c6ec4 <+32>: stur xzr, [x29, #-0x18] 0x1052c6ec8 <+36>: cmp w1, #0x0 0x1052c6ecc <+40>: csel x8, x9, x8, ne 0x1052c6ed0 <+44>: ldr x10, [x0, #0x48] 0x1052c6ed4 <+48>: cmp x10, #0x0 0x1052c6ed8 <+52>: csel x9, x9, x10, eq 0x1052c6edc <+56>: stp x9, x0, [sp, #0x10] 0x1052c6ee0 <+60>: adrp x9, 63 0x1052c6ee4 <+64>: add x9, x9, #0x9db ; "BUG IN CLIENT OF LIBDISPATCH: Assertion failed: " 0x1052c6ee8 <+68>: stp x9, x8, [sp] 0x1052c6eec <+72>: adrp x1, 63 0x1052c6ef0 <+76>: add x1, x1, #0x9a6 ; "%sBlock was %sexpected to execute on queue [%s (%p)]" 0x1052c6ef4 <+80>: sub x0, x29, #0x18 0x1052c6ef8 <+84>: bl 0x105301b18 ; symbol stub for: asprintf 0x1052c6efc <+88>: ldur x19, [x29, #-0x18] 0x1052c6f00 <+92>: str x19, [sp] 0x1052c6f04 <+96>: adrp x0, 63 0x1052c6f08 <+100>: add x0, x0, #0xa11 ; "%s" 0x1052c6f0c <+104>: bl 0x1052f9ef8 ; _dispatch_log 0x1052c6f10 <+108>: adrp x8, 95 0x1052c6f14 <+112>: str x19, [x8, #0x1f0] -> 0x1052c6f18 <+116>: brk #0x1 The app still crashes when I comment this code, and all Core Data related warnings. I'm quite stuck now as I want to use Swift 6. Has anyone figured CloudKit, CoreData and Swift 6 for sharing between users?

My Code: let op = CKModifyRecordsOperation(recordIDsToDelete:recordIDsToDelete) op.modifyRecordsCompletionBlock = { _, deleteRecordIDs, error in if error == nil { print("successful delete deleteRecordIDS = \(deleteRecordIDs)") } else { print("delete error = \(error?.localizedDescription)") } } op.database = CKContainer.default().privateCloudDatabase op.qualityOfService = .userInitiated CKContainer.default().privateCloudDatabase.add(op) My problem is that CKRecord are not deleted once I reinstall the app: when I reinstall the app and try to delete a CloudKit record, the method is executed successfully (error is nil) but the records are still in CloudKit Dashboards.

Hi Writing an app in Swift on Xcode for my iPhone, all software is the latest version. If after making a minor change and re-building all the application data has disappeared, is there a way to see if it is still in the .modelContainer and just not showing up?

Hi, I’m completely stuck with a very strange CloudKit problem that started recently and has now killed all iCloud sync for a live production app. What is happening Production container: iCloud.gainzCloud (created ~11 months ago, has been working perfectly until now) In Xcode 26.0 (17A321): → Signing & Capabilities → iCloud is enabled → Container correctly shows as iCloud.gainzCloud → App builds and runs on device/simulator with zero provisioning or container errors CloudKit Dashboard (https://icloud.developer.apple.com/dashboard/): completely blank – “No containers found” Result: CloudKit sync is dead for every user (development + production environments) What I know for sure Apple Developer Support confirmed the container iCloud.gainzCloud still exists and is correctly attached to my Team ID on their backend Personal iCloud (Mail, Notes, Photos, etc.) syncs perfectly on the same Mac / same Apple ID under macOS Tahoe 26.1 I have NOT changed the password on either the Apple ID or the Developer Program account New containers I create appear in Xcode but never show up in the Dashboard Environment macOS Tahoe 26.1 (latest) Xcode Version 26.0 (17A321) Has anyone on the new Tahoe/Xcode 26 releases seen the CloudKit Dashboard suddenly go completely empty while Xcode still “sees” the container just fine? Any known trick to force the dashboard to re-index containers or clear whatever cache is broken? Thanks a lot in advance – this is blocking all iCloud functionality for a released app with active users.