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CloudKit Query (and Dashboard) returns only a few records
When I query, an existing database with over 10,000 records from an Objective C app (i.e. CKQueryOperation) I get only N x 100 records returned where N varies each time between 0 and about 10 (i.e. never more than 1000 records and always an even multiple of 100). When I do a “Query Records” on the CloudKit Dashboard I get a similar number of pages of records downloaded (i.e. 0-10). If I tap “Query Records” multiple times I will get more pages of records until the full 10,000 are downloaded. This had been working fine until recently, both from the app and the Dashboard. There are multiple Record Types in the database. Only one Record Type is erroring. The other Record Types continue to work both from the app and the Dashboard. In particular, the Users Record Type has many many records and they all download to many pages with a single tap of “Query Records”. I have posted this to the Feedback Assistant under FB22358865. Here is my code: NSPredicate *predicate =[NSPredicate predicateWithFormat:@"modificationDate>%@",dateLastSynched]; CKRecordType theRecordName=[NSString stringWithString:@"Notices”]; // I also try this for @“Links” and @“Messages” and @“EventMessages" CKQuery *query = [[CKQuery alloc] initWithRecordType:theRecordName predicate:predicate]; CKQueryOperation *theOperation=[[CKQueryOperation alloc] initWithQuery:query]; [self startAQueryOperation:(CKQueryOperation *)theOperation theName:(NSString *)recordName]; -(void)startAQueryOperation:(CKQueryOperation *)theOperation theName:(NSString *)recordName{ theOperation.recordFetchedBlock=^(CKRecord *theRecord){ NSLog(@"XXXjust downloaded a %@",recordName); }; theOperation.queryCompletionBlock=^(CKQueryCursor *theCursor, NSError *error){ if(error){ NSLog(@"XXXerror %@",error); } if(theCursor){ CKQueryOperation *anotherOperation=[[CKQueryOperation alloc] initWithCursor:theCursor]; [self startAQueryOperation:anotherOperation theName:recordName]; } }; CKDatabase *publicDatabase = [[CKContainer defaultContainer] publicCloudDatabase]; [publicDatabase addOperation:theOperation]; } When I run this code in the app I get no “XXXerror” from the NSLogs. I get the expected number of “XXXjust downloaded a” EventMessages (435) and Messages (594) and Links (15) but I get varying amounts, 100 or 400 or 500 “xxjust downloaded a” for the Notices when I should get 10,118 records. Thinking that 10,000 records is too much, if I alter “dateLastSynched” for Notices I still get only 100 or 200, not the expected number. Note that the number is always a multiple of 100. This seems to be consistent with the typical number of records I get on the CloudKit dashboard each time I tap “Query Records”.
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1.3k
Jun ’26
Clarification on Current CloudKit CKAsset File Size Limits
Hi, I’m trying to find an authoritative and up-to-date answer regarding the maximum file size supported by CKAsset uploads in CloudKit. I know Apple documentation has historically referenced a 50 MB limit in some places, but from what I can tell, that limit appears to specifically apply to CloudKit Web Services rather than native CloudKit framework usage through CKAsset. At the same time, I frequently see reports from developers claiming they are successfully uploading significantly larger assets through CloudKit, sometimes well beyond 50 MB. However, I haven’t been able to find clear documentation confirming whether this behavior is officially supported, recommended, or simply tolerated under certain conditions. My use case involves potentially syncing assets larger than 50 MB, and I need to determine whether: CloudKit officially supports larger CKAsset uploads today There is a documented hard limit for native CloudKit CKAsset uploads Uploading larger assets is considered reliable/safe for production apps I should instead design around chunked uploads and reconstruction logic I’m specifically interested in current practical and documented limits for CKAsset in 2026, especially for private database usage on Apple platforms. If anyone from Apple or developers with production experience can clarify this, I’d appreciate it. I also opened a DTS incident regarding this question and was advised to ask on the forums so the answer can benefit other developers. Thanks. (I also opened a DTS incident regarding this question and was advised to ask on the forums so the answer can benefit other developers.)
2
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1.3k
May ’26
SwiftData 100% crash when fetching history with codable (test included!)
SwiftData crashes 100% when fetching history of a model that contains an optional codable property that's updated: SwiftData/Schema.swift:389: Fatal error: Failed to materialize a keypath for someCodableID.someID from CrashModel. It is possible that this path traverses a type that does not work with append(), please file a bug report with a test. Would really appreciate some help or even a workaround. Code: import Foundation import SwiftData import Testing struct VaultsSwiftDataKnownIssuesTests { @Test func testCodableCrashInHistoryFetch() async throws { let container = try ModelContainer( for: CrashModel.self, configurations: .init( isStoredInMemoryOnly: true ) ) let context = ModelContext(container) try SimpleHistoryChecker.hasLocalHistoryChanges(context: context) // 1: insert a new value and save let model = CrashModel() model.someCodableID = SomeCodableID(someID: "testid1") context.insert(model) try context.save() // 2: check history it's fine. try SimpleHistoryChecker.hasLocalHistoryChanges(context: context) // 3: update the inserted value before then save model.someCodableID = SomeCodableID(someID: "testid2") try context.save() // The next check will always crash on fetchHistory with this error: /* SwiftData/Schema.swift:389: Fatal error: Failed to materialize a keypath for someCodableID.someID from CrashModel. It is possible that this path traverses a type that does not work with append(), please file a bug report with a test. */ try SimpleHistoryChecker.hasLocalHistoryChanges(context: context) } } @Model final class CrashModel { // optional codable crashes. var someCodableID: SomeCodableID? // these actually work: //var someCodableID: SomeCodableID //var someCodableID: [SomeCodableID] init() {} } public struct SomeCodableID: Codable { public let someID: String } final class SimpleHistoryChecker { static func hasLocalHistoryChanges(context: ModelContext) throws { let descriptor = HistoryDescriptor<DefaultHistoryTransaction>() let history = try context.fetchHistory(descriptor) guard let last = history.last else { return } print(last) } }
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618
May ’26
macOS Tahoe: Denying iCloud access leaves users permanently locked out – no UI recovery path (Regression from Sequoia)
Hi, I'm the developer of Mail Signature (MAS, bundle ID: de.metaflash.mail-signature), a Mac app that uses iCloud Drive to sync email signatures. On macOS Tahoe, when a user denies the iCloud access permission dialog on first launch, there is absolutely no way to reverse that decision through System Settings. Regression from Sequoia: On Sequoia, after denying iCloud access, the app correctly appears under System Settings → Privacy & Security → Files and Folders where the user can toggle access back on. On Tahoe, the app does not appear anywhere in Privacy & Security after denial – not under Files and Folders, not under Apple ID → iCloud, nowhere. Technical details: Affected TCC services: kTCCServiceUbiquity + kTCCServiceLiverpool tccutil reset Ubiquity alone is insufficient Only tccutil reset All triggers the dialog again This suggests both services need to be reset simultaneously Impact: Normal users are permanently locked out with zero recovery path. The only workaround is Terminal: tccutil reset All de.metaflash.mail-signature ...which is completely inaccessible to average consumers. As a MAS developer we have no way to help users programmatically: exec/child_process → sandbox blocked NSUserUnixTask → designed for user-supplied scripts only, not reliable here Apple Events to Terminal → blocked or App Review risk Feedback submitted: FB22746525 Is anyone else seeing this? Would appreciate dups on the Feedback report. Any workaround suggestions from DTS welcome.
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953
May ’26
CKQuerySubscription on public database failing with BAD_REQUEST in Production — distinct from iOS 26.4 silent-push regression
Hello, I'm hitting a persistent CKQuerySubscription save failure on the public database in my Production CloudKit container. I want to flag this is NOT the iOS 26.4 silent-push regression resolved in 26.4.1 (I've confirmed it manifests differently and on devices that predate that bug). App: Win 10 Min (com.luiz.PandaApp) Container: iCloud.com.luiz.PandaApp Current shipping version: 3.2.1 build 420 (approved 2026-05-19) Public database THE ERROR (captured from CKError.userInfo) CKErrorCode 12 (badRequest) CKInternalErrorDomain code 2006 ("BadSyntax") ServerErrorDescription: "attempting to create a subscription in a production container" Execution time per failed attempt: 45-90ms (gateway-level rejection, not data validation). CODE let subscription = CKQuerySubscription( recordType: "GuardianRequest", predicate: NSPredicate(format: "guardianRecordName == %@", me), subscriptionID: "guardian-incoming-(me)", options: [.firesOnRecordCreation] ) let info = CKSubscription.NotificationInfo() info.shouldSendContentAvailable = true subscription.notificationInfo = info try await container.publicCloudDatabase.save(subscription) The .save() throws every time. REPRODUCES ACROSS iPhone on iOS 26.4.2 (i.e., has the 26.4.1 CloudKit regression fix) iPhone on iOS 18.6.x (predates the 26.4 regression entirely) Multiple distinct Apple IDs / userId hashes Fresh installs via TestFlight Updated installs from production CONSISTENTLY: USER_ERROR / BAD_REQUEST. Same error every time. WHY THIS ISN'T THE iOS 26.4 REGRESSION (Thread 820562) That regression caused silent notifications to be DROPPED client-side AFTER successful subscription creation. Our failure is SubscriptionCreate itself being rejected by the CloudKit server before any subscription exists. Different layer, different symptom. iOS 18.6.x devices also fail (they never had the 26.4 token-validation regression code). CLOUDKIT CONSOLE LOGS (sample request UUIDs Apple engineers can lookup) EB30E9D0-8C97-4685-BD16-3E79B3328D6F (2026-05-17 8:08 UTC) EEAA0606-5B50-4640-A950-EEA33B790B8E (2026-05-17, captured in-app) EB4C90CE-9172-4942-B00F-DE4A28388FBA (2026-05-19 7:18 UTC, iOS 18.6.x) F2DF69D9-2339-437A-B59B-7FBD4D57442F (2026-05-19 7:51 UTC, iOS 26.4.x) CloudKit Console → Production → Subscriptions: 0 entries despite 70+ attempts since 2026-05-11. WHAT I'VE VERIFIED / TRIED Schema: GuardianRequest.guardianRecordName and GuardianResponse.requesterRecordName both have QUERYABLE indexes in the Production schema (confirmed in Console). Field types: all STRING. aps-environment entitlement: "production" (changed from "development" in build 420; no change in error pattern). Push Notifications capability: enabled on App ID in Developer Portal AND in Xcode Signing & Capabilities for the main app target. UIBackgroundModes: includes "remote-notification". Re-deployed Production schema from Development on 2026-05-19 (Console reported "no changes"; failure pattern unchanged). Tried with and without info.desiredKeys = []. RecordQuery operations on the same fields and record types in the same container succeed consistently. QUESTIONS Is there a known infrastructure issue affecting public database CKQuerySubscription creation that is distinct from the iOS 26.4 regression (thread 820562)? Is there a per-container configuration that may be in an unexpected state, and if so what should I check? Are there workarounds beyond schema redeployment that have helped other developers in similar situations? Thanks for any guidance.
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965
May ’26
CloudKit console truncates the rows when there are too many
I believe the CloudKit console has an issue when displaying a large number of rows (around 1,677). If I don't perform any filtering and make sure I am on page one (by scrolling to the bottom and ensuring there is only a 'next' button and no 'previous' button), sorting by 'Created' only shows records up to the year 2024. However, if I apply a text filter to search for the latest record, my 2026 records appear correctly. I have attached a screenshot for your reference. I am testing it under Development environment. I am looking at the private database / com.apple.coredata.cloudkit.zone. I had to add the recordName index to browse this data
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786
May ’26
-startDownloadingUbiquitousItemAtURL:error: and NSURLUbiquitousItemDownloadRequestedKey
I'm trying to update the iCloud data handling in our app, and I'm running into an issue with a particular file on one particular device. This file never downloads & I haven't been able to pinpoint what's off about it. Right now we just have 2 iCloud accounts & a handful of devices, so I haven't been able to narrow it down yet, but in most cases, all the cloud files download as expected. However, whether or not the file eventually downloads, the NSURLUbiquitousItemDownloadRequestedKey key seems to be completely useless. For the following code: NSError *error = nil; BOOL success = [[NSFileManager defaultManager] startDownloadingUbiquitousItemAtURL:self.fileURL error:&error]; if (!success) { NSLog(@"error downloading %@ : %@", self.fileURL, error); } else { NSDictionary *resourceValues = [self.fileURL resourceValuesForKeys:@[NSURLUbiquitousItemDownloadRequestedKey, NSURLUbiquitousItemIsDownloadingKey, NSURLUbiquitousItemDownloadingErrorKey, NSURLUbiquitousItemDownloadingStatusKey] error:&error]; if (!error) { NSString *downloadStatus = resourceValues[NSURLUbiquitousItemDownloadingStatusKey]; bool downloadRequested = [resourceValues[NSURLUbiquitousItemDownloadRequestedKey] boolValue]; NSLog(@"download requested: %d", downloadRequested); } // ... } downloadRequested is always false, regardless of whether or not the cloud file eventually downloads. I have 2 questions: is there a way to actually check if a download has been requested for a file? what could be preventing this file from downloading? -startDownloadingUbiquitousItemAtURL:error: doesn't report an error, NSURLUbiquitousItemDownloadingErrorKey is always nil, and no error is reported in the NSMetadataQuery observer.
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1.3k
May ’26
Can Core Data avoid index rebuild when adding a new attribute during lightweight migration?
I’m investigating Core Data lightweight migration behavior with SQLite and ran into a performance issue. Scenario: Model V1: EntityA has one fetchIndex Model V2: EntityA adds a new optional attribute timestamp (Integer 64), with no changes to existing attributes or fetchIndex definitions From a SQLite perspective, this change should be handled by a simple: ALTER TABLE ZENTITYA ADD COLUMN ZTIMESTAMP INTEGER But I observe that Core Data rebuilds the existing index, which becomes a significant performance issue for large databases. CoreData: sql: DROP INDEX IF EXISTS Z_EntityA_id CoreData: sql: ALTER TABLE ZENTITYA ADD COLUMN ZTIMESTAMP INTEGER CoreData: sql: CREATE INDEX IF NOT EXISTS Z_EntityA_byID ON ZENTITYA Question: Is there any way to avoid or bypass index rebuilding for this kind of schema changes?
3
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635
May ’26
CloudKit CKRecordZone Deletion 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
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759
May ’26
CloudKit private database operations fail with CKError 15 / HTTP 500 for one container across multiple apps (FB22539748)
We are seeing a CloudKit private database failure for this specific container: iCloud.com.matrixqlc.photodiet.sync Failure pattern: accountStatus succeeds in some cases ensure/create custom zone succeeds but record/database-level operations consistently fail with: CKErrorDomain code = 15 CKInternalErrorDomain code = 2000 HTTP 500 Failing operations include: allRecordZones() databaseChanges(since:nil) allSubscriptions() fetch record zone metadata save record fetch record query records What makes this unusual is that the issue follows the container, not the app. On the same physical device, same Apple ID, same developer team: PhotoDiet + iCloud.com.matrixqlc.photodiet.sync => fails RepaymentCalculator + iCloud.com.matrixqlc.photodiet.sync => fails PhotoDiet + iCloud.com.matrixqlc.repaymentcalculator.sync2 => succeeds RepaymentCalculator + iCloud.com.matrixqlc.repaymentcalculator.sync2 => succeeds So this does not currently look like: app-specific entitlement/provisioning issues device/account issues CloudKit API misuse in one app record schema or app business logic issues It currently looks like the container iCloud.com.matrixqlc.photodiet.sync itself may be in a bad backend state. Sample request identifiers: RequestUUID: C8403047-0037-4D36-A7A7-CF3C83584A42 RequestUUID: 04437D9D-115E-45F5-87B5-A8CD146AE705 RequestUUID: C924B620-BAEE-403D-B944-151ADCF3419F RequestUUID: A54E79E1-6037-4533-BA09-18FBC436851C RequestUUID: 3EFD8913-3781-47CF-A48C-B651BF38EA50 RequestUUID: 2677A991-40B3-42AB-9CE5-3C4F1288EE08 Feedback Assistant ID: FB22539748 Has anyone seen a container-specific CloudKit private database failure like this, where multiple apps under the same team can access one container normally but consistently fail on another container with CKError 15 / HTTP 500?
3
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975
May ’26
Core Data Multiple NSEntityDescriptions claim the NSManagedObject subclass
Hello everyone, I'm trying to adopt the new Staged Migrations for Core Data and I keep running into an error that I haven't been able to resolve. The error messages are as follows: warning: Multiple NSEntityDescriptions claim the NSManagedObject subclass 'Movie' so +entity is unable to disambiguate. warning: 'Movie' (0x60000350d6b0) from NSManagedObjectModel (0x60000213a8a0) claims 'Movie'. error: +[Movie entity] Failed to find a unique match for an NSEntityDescription to a managed object subclass This happens for all of my entities when they are added/fetched. Movie is an abstract entity subclass, and it has the error error: +[Movie entity] Failed to find which is unique to the subclass entities, but this occurs for all entities. The NSPersistentContainer is loaded only once, and I set the following option after it's loaded: storeDescription.setOption( [stages], forKey: NSPersistentStoreStagedMigrationManagerOptionKey ) The warnings and errors only appear after I fetch or save to context. It happens regardless of whether the database was migrated or not. In my test project, using the generic NSManagedObject with NSEntityDescription.insertNewObject(forEntityName: "MyEntity", into: context) does not cause the issue. However, using the generic NSManagedObject is not a viable option for my app. Setting the module to "Current Project Module" doesn't change anything, except that it now prints "claims 'MyModule.Show'" in the warnings. I have verified that there are no other entities with the same name or renameIdentifier. Has anyone else encountered this issue, or can offer any suggestions on how to resolve it? Thanks in advance for any help!
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635
May ’26
CloudKit container in a broken state
I'm a first time developer, relying heavily on Claude Agent. In my app, I'm using CloudKit to sync data between devices, but after a migration something got corrupted and syncing is no longer working. I'm using SwiftData with NSPersistentCloudKitContainer. I'm using Xcode 26.4.1 on a Mac mini. I'm testing my app on the same Mac mini, running Tahoe 26.4.1 as well as an iPad 12.9 running iPadOS 26.3.1 and an iPhone running iOS 18.7.8. Sync stopped after a cachedTotal property was added to a SwiftData model, which triggered a backfill migration that wrote to all records simultaneously across multiple devices. This was followed by an iCloud sign-out/sign-in on the Mac. Here’s a summary of everything I’ve tried already: Reset All Data on all devices multiple times Deleted and reinstalled the app on all devices Deleted the CloudKit zone twice Force-deleted local SQLite store files to clear change tokens Zone and subscription both appear correct in the dashboard Change token updates when data is written (confirming uploads work) No data propagates to other devices in any direction Uploads appear to succeed (change token changes) but imports never fire on any device. In other words, writes work, reads don’t. Is there a way to fully reset the CloudKit container's production private database for a TestFlight app, or is there a way to diagnose why imports are not firing despite a valid zone and subscription?
2
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668
May ’26
'NSKeyedUnarchiveFromData' should not be used to for un-archiving and will be removed in a future release
Hi, Overview: I get the following error when trying to save / read from SwiftData It happens when I try to save color to SwiftData (code below) Error 'NSKeyedUnarchiveFromData' should not be used to for un-archiving and will be removed in a future release Questions How can I resolve the error? I am not directly using data, I am using just Float values, swift types. Why am I getting this error? Is there a way to add a breakpoint to stop at the exact type causing the error? (Symbolic breakpoint doesn't seem to help) Or is the below code ok and not responsible for the error? Code import SwiftUI nonisolated struct ColorRepresentation: Codable { let red: Float let green: Float let blue: Float let opacity: Float init(colorResolved: Color.Resolved) { red = colorResolved.red green = colorResolved.green blue = colorResolved.blue opacity = colorResolved.opacity } func color() throws -> Color { Color( red: Double(red), green: Double(green), blue: Double(blue), opacity: Double(opacity) ) } } extension ColorRepresentation: Equatable {}
9
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1.1k
May ’26
CKShare-style user-to-user sharing support in SwiftData
Hello everyone, I've really been enjoying SwiftData's approach to handling DBs, however sharing data between users has caused me quite some headaches. I am currently developing an app for my local theatre that will help the assistant directors with production planning and would need a way to share data. On some big productions we have 2 ADs, so they'd need to be able to share the project and do collaborative work on it. I don't need fancy real-time editing or anything. However, SwiftData exposing an equivalent to Core Data’s NSPersistentCloudKitContainer sharing APIs for CKShare-based user-to-user collaboration would be amazing. As the only thing supported is per-user private data sync, I’m currently considering a hybrid approach until the full project could be shared: SwiftData for the main private app data a small separate Core Data + CloudKit sharing stack only for the shared timetables for cast and crew Is that the recommended implementation today, or is there a better SwiftData-friendly way to do this? I also filed Feedback Assistant request FB22712510 asking for native SwiftData support for user-to-user CloudKit sharing. Thanks for any pointers or help! Best regards, Aedan
1
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735
May ’26
CloudKit: Records not indexing
Since publishing new record types to my CloudKit schema in production, a previously unchanged record type has stopped indexing new records. While records of this type are successfully saved without errors, they are not returned in query results—they can only be accessed directly via their recordName. This issue occurs exclusively in the Production environment, both in the CloudKit Console and our iOS app. The problem began on July 21, 2025, and continues to persist. The issue affects only new records of this specific record type; all other types are indexing and querying as expected. The affected record's fields are properly configured with the appropriate index types (e.g., QUERYABLE) and have been not been modified prior to publishing the schema. With this, are there any steps I should take to restore indexing functionality for this record type in Production? There have been new records inserted, and I would prefer to not have to reset the production database, if possible.
5
1
2.1k
Apr ’26
SwiftData+Cloudkit and records with CKAsset import on fresh install never ends.
I’m using SwiftData with CloudKit and running into an issue during initial sync on a fresh device. I’m importing a small set of records, some records has images as CKAsset (with about 5 images ~3MB). Records indexes are the default ones for the Dev env. The problem is that the import process never seems to complete. However, if I delete those records that contains the assets from the iCloud Dashboard, the import finishes successfully. Has anyone experienced something similar? What approach would you recommend to handle this without implementing a custom sync layer on top of CloudKit? I am logging remote changes events (NSPersistentStoreRemoteChange): CloudKit import in progress...|2026-04-25 22:18:10| Then I see: Background Task 49 ("CoreData: CloudKit Import"), was created over 30 seconds ago. In applications running in the background, this creates a risk of termination. Remember to call UIApplication.endBackgroundTask(_:) for your task in a timely manner to avoid this. And then the import never ends. Thanks!
1
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726
Apr ’26
CloudKit, cannot deploy private database initial schema to production
We’re using a private database with a custom zone. Record types and related schema are created programmatically rather than through the dashboard. When running the app in the development environment, I can see that data is saved and can be retrieved successfully. However, in the iCloud console, I don’t see any record types or even the custom zone. Additionally, I’m unable to deploy any schema to production because no changes are detected. Do you have any ideas on what we might be missing? Installing the app from TestFlight when trying to upload a record CloudKit reports this error: <CKError 0x13f40bb10: "Invalid Arguments" (12/2006); server message = "Cannot create new type MyType in production schema" ...>
2
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935
Apr ’26
SwiftData document-based app crashes on undo/redo without ModelContext.transaction(block:)
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 // }
0
0
859
Apr ’26
iCloud Drive silent upload deadlock caused by stale HTTP/3 session in nsurlsessiond (FB22476701)
Summary On macOS 26.4.1 (25E253), iCloud Drive file uploads can enter a silent deadlock where every upload attempt fails at the transport layer. No error is surfaced anywhere — not in Finder, not in System Settings, not in the iCloud status panel. The upload queue simply stops. Other iCloud services (Photos, Mail, App Store) continue to work normally through the same networking infrastructure at the same time. Root Cause The issue is a stale HTTP/3 (QUIC) session cached in the user-level nsurlsessiond process's BackgroundConnectionPool. The deadlock cycle: cloudd requests an upload to the GCS storage endpoint nsurlsessiond provides the cached (broken) HTTP/3 session The TLS handshake succeeds, but the body upload dies mid-transfer (err=T, requestDuration=-1.000, responseHeaderBytes=0) cloudd retries with a new connectionUUID — but nsurlsessiond still routes through the same poisoned QUIC session This repeats indefinitely Killing cloudd alone does not help — nsurlsessiond retains the poisoned pool. Only killing both the user-level cloudd and nsurlsessiond clears the pool and forces a fresh protocol negotiation. The Smoking Gun After killing both daemons, the system falls back to HTTP/1.1 for the stuck uploads — and they complete instantly: Before Kill After Kill Protocol h3 (QUIC) http/1.1 (TCP) Largest upload Failed at partial offsets 26 MB in 1.6 seconds Server response 0 bytes 596 bytes (normal) Same endpoint, same files, same network interface (en5), same power state. The only change was the protocol negotiation after a fresh nsurlsessiond. Reproduction Reproduced 3 times on April 11, 2026 using a standardized set of 8 test files (8 bytes to 20 MB) in a non-shared iCloud Drive folder. Each run showed the identical pattern: Small files (<100 KB) squeeze through before the QUIC session stalls Larger files trigger the deadlock every time 5–6 retries with fresh connectionUUIDs, all failing over protocol=h3 After kill cloudd + nsurlsessiond: immediate flush via protocol=http/1.1 An automated evidence-collection script (collect_h3_deadlock_evidence.sh) captures paired before-kill / after-kill logs. Included in the Feedback report. Symptom Check (for others hitting this) /usr/bin/log show --predicate 'process == "cloudd"' --last 5m 2>&1 \ | grep "putContainer.*err=T.*requestDuration=-1.000.*protocol=h3" | wc -l Output > 0 = this deadlock. Output = 0 = different issue. Recovery (one-liner) kill $(ps -axo user,pid,command | awk -v u="$USER" \ '($1==u && /CloudKitDaemon.framework.*cloudd/ && !/--system/) \ || ($1==u && /\/usr\/libexec\/nsurlsessiond/ && !/--privileged/) \ {print $2}') Both daemons respawn within 1–2 seconds. Do not use killall nsurlsessiond — it would also kill the privileged system instance. What was ruled out Network connectivity (Photos uploaded 8 MB through the same pool simultaneously) iCloud account (metadata operations succeeding, only body uploads failing) File type/content (random data, correlation is with size, not type) Storage quota (1.65 TB free) CFNetworkHTTP3Enabled=false (key is ineffective in 26.4.1) Suggested fixes (from the Feedback report) CFNetwork: Invalidate the QUIC session after N consecutive requestDuration=-1.000 failures CloudKit/NSURLSession: Expose a pool invalidation API like [NSURLSession invalidatePoolEntryForEndpoint:] cloudd: Self-healing retry — create a fresh NSURLSession after M consecutive deadlock-signature failures Finder: At minimum, surface the stuck state to the user instead of failing silently Filed as FB22476701 — includes full reproduction timelines, request/connection UUIDs, sysdiagnose, and a 12-page investigation PDF with architecture diagrams and protocol comparison tables. If you're experiencing the same issue, please file a duplicate referencing FB22476701 — Apple prioritizes by duplicate count. System MacBook Air, macOS 26.4.1 (25E253) iCloud Drive with Desktop & Documents sync en0 (WLAN) + en5 (USB-LAN via Studio Display)
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Apr ’26
CloudKit Query (and Dashboard) returns only a few records
When I query, an existing database with over 10,000 records from an Objective C app (i.e. CKQueryOperation) I get only N x 100 records returned where N varies each time between 0 and about 10 (i.e. never more than 1000 records and always an even multiple of 100). When I do a “Query Records” on the CloudKit Dashboard I get a similar number of pages of records downloaded (i.e. 0-10). If I tap “Query Records” multiple times I will get more pages of records until the full 10,000 are downloaded. This had been working fine until recently, both from the app and the Dashboard. There are multiple Record Types in the database. Only one Record Type is erroring. The other Record Types continue to work both from the app and the Dashboard. In particular, the Users Record Type has many many records and they all download to many pages with a single tap of “Query Records”. I have posted this to the Feedback Assistant under FB22358865. Here is my code: NSPredicate *predicate =[NSPredicate predicateWithFormat:@"modificationDate>%@",dateLastSynched]; CKRecordType theRecordName=[NSString stringWithString:@"Notices”]; // I also try this for @“Links” and @“Messages” and @“EventMessages" CKQuery *query = [[CKQuery alloc] initWithRecordType:theRecordName predicate:predicate]; CKQueryOperation *theOperation=[[CKQueryOperation alloc] initWithQuery:query]; [self startAQueryOperation:(CKQueryOperation *)theOperation theName:(NSString *)recordName]; -(void)startAQueryOperation:(CKQueryOperation *)theOperation theName:(NSString *)recordName{ theOperation.recordFetchedBlock=^(CKRecord *theRecord){ NSLog(@"XXXjust downloaded a %@",recordName); }; theOperation.queryCompletionBlock=^(CKQueryCursor *theCursor, NSError *error){ if(error){ NSLog(@"XXXerror %@",error); } if(theCursor){ CKQueryOperation *anotherOperation=[[CKQueryOperation alloc] initWithCursor:theCursor]; [self startAQueryOperation:anotherOperation theName:recordName]; } }; CKDatabase *publicDatabase = [[CKContainer defaultContainer] publicCloudDatabase]; [publicDatabase addOperation:theOperation]; } When I run this code in the app I get no “XXXerror” from the NSLogs. I get the expected number of “XXXjust downloaded a” EventMessages (435) and Messages (594) and Links (15) but I get varying amounts, 100 or 400 or 500 “xxjust downloaded a” for the Notices when I should get 10,118 records. Thinking that 10,000 records is too much, if I alter “dateLastSynched” for Notices I still get only 100 or 200, not the expected number. Note that the number is always a multiple of 100. This seems to be consistent with the typical number of records I get on the CloudKit dashboard each time I tap “Query Records”.
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Jun ’26
Clarification on Current CloudKit CKAsset File Size Limits
Hi, I’m trying to find an authoritative and up-to-date answer regarding the maximum file size supported by CKAsset uploads in CloudKit. I know Apple documentation has historically referenced a 50 MB limit in some places, but from what I can tell, that limit appears to specifically apply to CloudKit Web Services rather than native CloudKit framework usage through CKAsset. At the same time, I frequently see reports from developers claiming they are successfully uploading significantly larger assets through CloudKit, sometimes well beyond 50 MB. However, I haven’t been able to find clear documentation confirming whether this behavior is officially supported, recommended, or simply tolerated under certain conditions. My use case involves potentially syncing assets larger than 50 MB, and I need to determine whether: CloudKit officially supports larger CKAsset uploads today There is a documented hard limit for native CloudKit CKAsset uploads Uploading larger assets is considered reliable/safe for production apps I should instead design around chunked uploads and reconstruction logic I’m specifically interested in current practical and documented limits for CKAsset in 2026, especially for private database usage on Apple platforms. If anyone from Apple or developers with production experience can clarify this, I’d appreciate it. I also opened a DTS incident regarding this question and was advised to ask on the forums so the answer can benefit other developers. Thanks. (I also opened a DTS incident regarding this question and was advised to ask on the forums so the answer can benefit other developers.)
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May ’26
SwiftData 100% crash when fetching history with codable (test included!)
SwiftData crashes 100% when fetching history of a model that contains an optional codable property that's updated: SwiftData/Schema.swift:389: Fatal error: Failed to materialize a keypath for someCodableID.someID from CrashModel. It is possible that this path traverses a type that does not work with append(), please file a bug report with a test. Would really appreciate some help or even a workaround. Code: import Foundation import SwiftData import Testing struct VaultsSwiftDataKnownIssuesTests { @Test func testCodableCrashInHistoryFetch() async throws { let container = try ModelContainer( for: CrashModel.self, configurations: .init( isStoredInMemoryOnly: true ) ) let context = ModelContext(container) try SimpleHistoryChecker.hasLocalHistoryChanges(context: context) // 1: insert a new value and save let model = CrashModel() model.someCodableID = SomeCodableID(someID: "testid1") context.insert(model) try context.save() // 2: check history it's fine. try SimpleHistoryChecker.hasLocalHistoryChanges(context: context) // 3: update the inserted value before then save model.someCodableID = SomeCodableID(someID: "testid2") try context.save() // The next check will always crash on fetchHistory with this error: /* SwiftData/Schema.swift:389: Fatal error: Failed to materialize a keypath for someCodableID.someID from CrashModel. It is possible that this path traverses a type that does not work with append(), please file a bug report with a test. */ try SimpleHistoryChecker.hasLocalHistoryChanges(context: context) } } @Model final class CrashModel { // optional codable crashes. var someCodableID: SomeCodableID? // these actually work: //var someCodableID: SomeCodableID //var someCodableID: [SomeCodableID] init() {} } public struct SomeCodableID: Codable { public let someID: String } final class SimpleHistoryChecker { static func hasLocalHistoryChanges(context: ModelContext) throws { let descriptor = HistoryDescriptor<DefaultHistoryTransaction>() let history = try context.fetchHistory(descriptor) guard let last = history.last else { return } print(last) } }
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618
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May ’26
macOS Tahoe: Denying iCloud access leaves users permanently locked out – no UI recovery path (Regression from Sequoia)
Hi, I'm the developer of Mail Signature (MAS, bundle ID: de.metaflash.mail-signature), a Mac app that uses iCloud Drive to sync email signatures. On macOS Tahoe, when a user denies the iCloud access permission dialog on first launch, there is absolutely no way to reverse that decision through System Settings. Regression from Sequoia: On Sequoia, after denying iCloud access, the app correctly appears under System Settings → Privacy & Security → Files and Folders where the user can toggle access back on. On Tahoe, the app does not appear anywhere in Privacy & Security after denial – not under Files and Folders, not under Apple ID → iCloud, nowhere. Technical details: Affected TCC services: kTCCServiceUbiquity + kTCCServiceLiverpool tccutil reset Ubiquity alone is insufficient Only tccutil reset All triggers the dialog again This suggests both services need to be reset simultaneously Impact: Normal users are permanently locked out with zero recovery path. The only workaround is Terminal: tccutil reset All de.metaflash.mail-signature ...which is completely inaccessible to average consumers. As a MAS developer we have no way to help users programmatically: exec/child_process → sandbox blocked NSUserUnixTask → designed for user-supplied scripts only, not reliable here Apple Events to Terminal → blocked or App Review risk Feedback submitted: FB22746525 Is anyone else seeing this? Would appreciate dups on the Feedback report. Any workaround suggestions from DTS welcome.
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953
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May ’26
CKQuerySubscription on public database failing with BAD_REQUEST in Production — distinct from iOS 26.4 silent-push regression
Hello, I'm hitting a persistent CKQuerySubscription save failure on the public database in my Production CloudKit container. I want to flag this is NOT the iOS 26.4 silent-push regression resolved in 26.4.1 (I've confirmed it manifests differently and on devices that predate that bug). App: Win 10 Min (com.luiz.PandaApp) Container: iCloud.com.luiz.PandaApp Current shipping version: 3.2.1 build 420 (approved 2026-05-19) Public database THE ERROR (captured from CKError.userInfo) CKErrorCode 12 (badRequest) CKInternalErrorDomain code 2006 ("BadSyntax") ServerErrorDescription: "attempting to create a subscription in a production container" Execution time per failed attempt: 45-90ms (gateway-level rejection, not data validation). CODE let subscription = CKQuerySubscription( recordType: "GuardianRequest", predicate: NSPredicate(format: "guardianRecordName == %@", me), subscriptionID: "guardian-incoming-(me)", options: [.firesOnRecordCreation] ) let info = CKSubscription.NotificationInfo() info.shouldSendContentAvailable = true subscription.notificationInfo = info try await container.publicCloudDatabase.save(subscription) The .save() throws every time. REPRODUCES ACROSS iPhone on iOS 26.4.2 (i.e., has the 26.4.1 CloudKit regression fix) iPhone on iOS 18.6.x (predates the 26.4 regression entirely) Multiple distinct Apple IDs / userId hashes Fresh installs via TestFlight Updated installs from production CONSISTENTLY: USER_ERROR / BAD_REQUEST. Same error every time. WHY THIS ISN'T THE iOS 26.4 REGRESSION (Thread 820562) That regression caused silent notifications to be DROPPED client-side AFTER successful subscription creation. Our failure is SubscriptionCreate itself being rejected by the CloudKit server before any subscription exists. Different layer, different symptom. iOS 18.6.x devices also fail (they never had the 26.4 token-validation regression code). CLOUDKIT CONSOLE LOGS (sample request UUIDs Apple engineers can lookup) EB30E9D0-8C97-4685-BD16-3E79B3328D6F (2026-05-17 8:08 UTC) EEAA0606-5B50-4640-A950-EEA33B790B8E (2026-05-17, captured in-app) EB4C90CE-9172-4942-B00F-DE4A28388FBA (2026-05-19 7:18 UTC, iOS 18.6.x) F2DF69D9-2339-437A-B59B-7FBD4D57442F (2026-05-19 7:51 UTC, iOS 26.4.x) CloudKit Console → Production → Subscriptions: 0 entries despite 70+ attempts since 2026-05-11. WHAT I'VE VERIFIED / TRIED Schema: GuardianRequest.guardianRecordName and GuardianResponse.requesterRecordName both have QUERYABLE indexes in the Production schema (confirmed in Console). Field types: all STRING. aps-environment entitlement: "production" (changed from "development" in build 420; no change in error pattern). Push Notifications capability: enabled on App ID in Developer Portal AND in Xcode Signing & Capabilities for the main app target. UIBackgroundModes: includes "remote-notification". Re-deployed Production schema from Development on 2026-05-19 (Console reported "no changes"; failure pattern unchanged). Tried with and without info.desiredKeys = []. RecordQuery operations on the same fields and record types in the same container succeed consistently. QUESTIONS Is there a known infrastructure issue affecting public database CKQuerySubscription creation that is distinct from the iOS 26.4 regression (thread 820562)? Is there a per-container configuration that may be in an unexpected state, and if so what should I check? Are there workarounds beyond schema redeployment that have helped other developers in similar situations? Thanks for any guidance.
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965
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May ’26
Core Data for 2 level data
I'm attempting to create a feature where I can allow two levels of information
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915
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May ’26
CloudKit console truncates the rows when there are too many
I believe the CloudKit console has an issue when displaying a large number of rows (around 1,677). If I don't perform any filtering and make sure I am on page one (by scrolling to the bottom and ensuring there is only a 'next' button and no 'previous' button), sorting by 'Created' only shows records up to the year 2024. However, if I apply a text filter to search for the latest record, my 2026 records appear correctly. I have attached a screenshot for your reference. I am testing it under Development environment. I am looking at the private database / com.apple.coredata.cloudkit.zone. I had to add the recordName index to browse this data
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786
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May ’26
-startDownloadingUbiquitousItemAtURL:error: and NSURLUbiquitousItemDownloadRequestedKey
I'm trying to update the iCloud data handling in our app, and I'm running into an issue with a particular file on one particular device. This file never downloads & I haven't been able to pinpoint what's off about it. Right now we just have 2 iCloud accounts & a handful of devices, so I haven't been able to narrow it down yet, but in most cases, all the cloud files download as expected. However, whether or not the file eventually downloads, the NSURLUbiquitousItemDownloadRequestedKey key seems to be completely useless. For the following code: NSError *error = nil; BOOL success = [[NSFileManager defaultManager] startDownloadingUbiquitousItemAtURL:self.fileURL error:&error]; if (!success) { NSLog(@"error downloading %@ : %@", self.fileURL, error); } else { NSDictionary *resourceValues = [self.fileURL resourceValuesForKeys:@[NSURLUbiquitousItemDownloadRequestedKey, NSURLUbiquitousItemIsDownloadingKey, NSURLUbiquitousItemDownloadingErrorKey, NSURLUbiquitousItemDownloadingStatusKey] error:&error]; if (!error) { NSString *downloadStatus = resourceValues[NSURLUbiquitousItemDownloadingStatusKey]; bool downloadRequested = [resourceValues[NSURLUbiquitousItemDownloadRequestedKey] boolValue]; NSLog(@"download requested: %d", downloadRequested); } // ... } downloadRequested is always false, regardless of whether or not the cloud file eventually downloads. I have 2 questions: is there a way to actually check if a download has been requested for a file? what could be preventing this file from downloading? -startDownloadingUbiquitousItemAtURL:error: doesn't report an error, NSURLUbiquitousItemDownloadingErrorKey is always nil, and no error is reported in the NSMetadataQuery observer.
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May ’26
Can Core Data avoid index rebuild when adding a new attribute during lightweight migration?
I’m investigating Core Data lightweight migration behavior with SQLite and ran into a performance issue. Scenario: Model V1: EntityA has one fetchIndex Model V2: EntityA adds a new optional attribute timestamp (Integer 64), with no changes to existing attributes or fetchIndex definitions From a SQLite perspective, this change should be handled by a simple: ALTER TABLE ZENTITYA ADD COLUMN ZTIMESTAMP INTEGER But I observe that Core Data rebuilds the existing index, which becomes a significant performance issue for large databases. CoreData: sql: DROP INDEX IF EXISTS Z_EntityA_id CoreData: sql: ALTER TABLE ZENTITYA ADD COLUMN ZTIMESTAMP INTEGER CoreData: sql: CREATE INDEX IF NOT EXISTS Z_EntityA_byID ON ZENTITYA Question: Is there any way to avoid or bypass index rebuilding for this kind of schema changes?
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635
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May ’26
CloudKit CKRecordZone Deletion 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
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759
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May ’26
CloudKit private database operations fail with CKError 15 / HTTP 500 for one container across multiple apps (FB22539748)
We are seeing a CloudKit private database failure for this specific container: iCloud.com.matrixqlc.photodiet.sync Failure pattern: accountStatus succeeds in some cases ensure/create custom zone succeeds but record/database-level operations consistently fail with: CKErrorDomain code = 15 CKInternalErrorDomain code = 2000 HTTP 500 Failing operations include: allRecordZones() databaseChanges(since:nil) allSubscriptions() fetch record zone metadata save record fetch record query records What makes this unusual is that the issue follows the container, not the app. On the same physical device, same Apple ID, same developer team: PhotoDiet + iCloud.com.matrixqlc.photodiet.sync => fails RepaymentCalculator + iCloud.com.matrixqlc.photodiet.sync => fails PhotoDiet + iCloud.com.matrixqlc.repaymentcalculator.sync2 => succeeds RepaymentCalculator + iCloud.com.matrixqlc.repaymentcalculator.sync2 => succeeds So this does not currently look like: app-specific entitlement/provisioning issues device/account issues CloudKit API misuse in one app record schema or app business logic issues It currently looks like the container iCloud.com.matrixqlc.photodiet.sync itself may be in a bad backend state. Sample request identifiers: RequestUUID: C8403047-0037-4D36-A7A7-CF3C83584A42 RequestUUID: 04437D9D-115E-45F5-87B5-A8CD146AE705 RequestUUID: C924B620-BAEE-403D-B944-151ADCF3419F RequestUUID: A54E79E1-6037-4533-BA09-18FBC436851C RequestUUID: 3EFD8913-3781-47CF-A48C-B651BF38EA50 RequestUUID: 2677A991-40B3-42AB-9CE5-3C4F1288EE08 Feedback Assistant ID: FB22539748 Has anyone seen a container-specific CloudKit private database failure like this, where multiple apps under the same team can access one container normally but consistently fail on another container with CKError 15 / HTTP 500?
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975
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May ’26
Core Data Multiple NSEntityDescriptions claim the NSManagedObject subclass
Hello everyone, I'm trying to adopt the new Staged Migrations for Core Data and I keep running into an error that I haven't been able to resolve. The error messages are as follows: warning: Multiple NSEntityDescriptions claim the NSManagedObject subclass 'Movie' so +entity is unable to disambiguate. warning: 'Movie' (0x60000350d6b0) from NSManagedObjectModel (0x60000213a8a0) claims 'Movie'. error: +[Movie entity] Failed to find a unique match for an NSEntityDescription to a managed object subclass This happens for all of my entities when they are added/fetched. Movie is an abstract entity subclass, and it has the error error: +[Movie entity] Failed to find which is unique to the subclass entities, but this occurs for all entities. The NSPersistentContainer is loaded only once, and I set the following option after it's loaded: storeDescription.setOption( [stages], forKey: NSPersistentStoreStagedMigrationManagerOptionKey ) The warnings and errors only appear after I fetch or save to context. It happens regardless of whether the database was migrated or not. In my test project, using the generic NSManagedObject with NSEntityDescription.insertNewObject(forEntityName: "MyEntity", into: context) does not cause the issue. However, using the generic NSManagedObject is not a viable option for my app. Setting the module to "Current Project Module" doesn't change anything, except that it now prints "claims 'MyModule.Show'" in the warnings. I have verified that there are no other entities with the same name or renameIdentifier. Has anyone else encountered this issue, or can offer any suggestions on how to resolve it? Thanks in advance for any help!
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635
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May ’26
CloudKit container in a broken state
I'm a first time developer, relying heavily on Claude Agent. In my app, I'm using CloudKit to sync data between devices, but after a migration something got corrupted and syncing is no longer working. I'm using SwiftData with NSPersistentCloudKitContainer. I'm using Xcode 26.4.1 on a Mac mini. I'm testing my app on the same Mac mini, running Tahoe 26.4.1 as well as an iPad 12.9 running iPadOS 26.3.1 and an iPhone running iOS 18.7.8. Sync stopped after a cachedTotal property was added to a SwiftData model, which triggered a backfill migration that wrote to all records simultaneously across multiple devices. This was followed by an iCloud sign-out/sign-in on the Mac. Here’s a summary of everything I’ve tried already: Reset All Data on all devices multiple times Deleted and reinstalled the app on all devices Deleted the CloudKit zone twice Force-deleted local SQLite store files to clear change tokens Zone and subscription both appear correct in the dashboard Change token updates when data is written (confirming uploads work) No data propagates to other devices in any direction Uploads appear to succeed (change token changes) but imports never fire on any device. In other words, writes work, reads don’t. Is there a way to fully reset the CloudKit container's production private database for a TestFlight app, or is there a way to diagnose why imports are not firing despite a valid zone and subscription?
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668
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May ’26
'NSKeyedUnarchiveFromData' should not be used to for un-archiving and will be removed in a future release
Hi, Overview: I get the following error when trying to save / read from SwiftData It happens when I try to save color to SwiftData (code below) Error 'NSKeyedUnarchiveFromData' should not be used to for un-archiving and will be removed in a future release Questions How can I resolve the error? I am not directly using data, I am using just Float values, swift types. Why am I getting this error? Is there a way to add a breakpoint to stop at the exact type causing the error? (Symbolic breakpoint doesn't seem to help) Or is the below code ok and not responsible for the error? Code import SwiftUI nonisolated struct ColorRepresentation: Codable { let red: Float let green: Float let blue: Float let opacity: Float init(colorResolved: Color.Resolved) { red = colorResolved.red green = colorResolved.green blue = colorResolved.blue opacity = colorResolved.opacity } func color() throws -> Color { Color( red: Double(red), green: Double(green), blue: Double(blue), opacity: Double(opacity) ) } } extension ColorRepresentation: Equatable {}
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May ’26
CKShare-style user-to-user sharing support in SwiftData
Hello everyone, I've really been enjoying SwiftData's approach to handling DBs, however sharing data between users has caused me quite some headaches. I am currently developing an app for my local theatre that will help the assistant directors with production planning and would need a way to share data. On some big productions we have 2 ADs, so they'd need to be able to share the project and do collaborative work on it. I don't need fancy real-time editing or anything. However, SwiftData exposing an equivalent to Core Data’s NSPersistentCloudKitContainer sharing APIs for CKShare-based user-to-user collaboration would be amazing. As the only thing supported is per-user private data sync, I’m currently considering a hybrid approach until the full project could be shared: SwiftData for the main private app data a small separate Core Data + CloudKit sharing stack only for the shared timetables for cast and crew Is that the recommended implementation today, or is there a better SwiftData-friendly way to do this? I also filed Feedback Assistant request FB22712510 asking for native SwiftData support for user-to-user CloudKit sharing. Thanks for any pointers or help! Best regards, Aedan
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735
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May ’26
CloudKit: Records not indexing
Since publishing new record types to my CloudKit schema in production, a previously unchanged record type has stopped indexing new records. While records of this type are successfully saved without errors, they are not returned in query results—they can only be accessed directly via their recordName. This issue occurs exclusively in the Production environment, both in the CloudKit Console and our iOS app. The problem began on July 21, 2025, and continues to persist. The issue affects only new records of this specific record type; all other types are indexing and querying as expected. The affected record's fields are properly configured with the appropriate index types (e.g., QUERYABLE) and have been not been modified prior to publishing the schema. With this, are there any steps I should take to restore indexing functionality for this record type in Production? There have been new records inserted, and I would prefer to not have to reset the production database, if possible.
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Apr ’26
SwiftData+Cloudkit and records with CKAsset import on fresh install never ends.
I’m using SwiftData with CloudKit and running into an issue during initial sync on a fresh device. I’m importing a small set of records, some records has images as CKAsset (with about 5 images ~3MB). Records indexes are the default ones for the Dev env. The problem is that the import process never seems to complete. However, if I delete those records that contains the assets from the iCloud Dashboard, the import finishes successfully. Has anyone experienced something similar? What approach would you recommend to handle this without implementing a custom sync layer on top of CloudKit? I am logging remote changes events (NSPersistentStoreRemoteChange): CloudKit import in progress...|2026-04-25 22:18:10| Then I see: Background Task 49 ("CoreData: CloudKit Import"), was created over 30 seconds ago. In applications running in the background, this creates a risk of termination. Remember to call UIApplication.endBackgroundTask(_:) for your task in a timely manner to avoid this. And then the import never ends. Thanks!
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726
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Apr ’26
CloudKit, cannot deploy private database initial schema to production
We’re using a private database with a custom zone. Record types and related schema are created programmatically rather than through the dashboard. When running the app in the development environment, I can see that data is saved and can be retrieved successfully. However, in the iCloud console, I don’t see any record types or even the custom zone. Additionally, I’m unable to deploy any schema to production because no changes are detected. Do you have any ideas on what we might be missing? Installing the app from TestFlight when trying to upload a record CloudKit reports this error: <CKError 0x13f40bb10: "Invalid Arguments" (12/2006); server message = "Cannot create new type MyType in production schema" ...>
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935
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Apr ’26
SwiftData document-based app crashes on undo/redo without ModelContext.transaction(block:)
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 // }
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859
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Apr ’26
iCloud Drive silent upload deadlock caused by stale HTTP/3 session in nsurlsessiond (FB22476701)
Summary On macOS 26.4.1 (25E253), iCloud Drive file uploads can enter a silent deadlock where every upload attempt fails at the transport layer. No error is surfaced anywhere — not in Finder, not in System Settings, not in the iCloud status panel. The upload queue simply stops. Other iCloud services (Photos, Mail, App Store) continue to work normally through the same networking infrastructure at the same time. Root Cause The issue is a stale HTTP/3 (QUIC) session cached in the user-level nsurlsessiond process's BackgroundConnectionPool. The deadlock cycle: cloudd requests an upload to the GCS storage endpoint nsurlsessiond provides the cached (broken) HTTP/3 session The TLS handshake succeeds, but the body upload dies mid-transfer (err=T, requestDuration=-1.000, responseHeaderBytes=0) cloudd retries with a new connectionUUID — but nsurlsessiond still routes through the same poisoned QUIC session This repeats indefinitely Killing cloudd alone does not help — nsurlsessiond retains the poisoned pool. Only killing both the user-level cloudd and nsurlsessiond clears the pool and forces a fresh protocol negotiation. The Smoking Gun After killing both daemons, the system falls back to HTTP/1.1 for the stuck uploads — and they complete instantly: Before Kill After Kill Protocol h3 (QUIC) http/1.1 (TCP) Largest upload Failed at partial offsets 26 MB in 1.6 seconds Server response 0 bytes 596 bytes (normal) Same endpoint, same files, same network interface (en5), same power state. The only change was the protocol negotiation after a fresh nsurlsessiond. Reproduction Reproduced 3 times on April 11, 2026 using a standardized set of 8 test files (8 bytes to 20 MB) in a non-shared iCloud Drive folder. Each run showed the identical pattern: Small files (<100 KB) squeeze through before the QUIC session stalls Larger files trigger the deadlock every time 5–6 retries with fresh connectionUUIDs, all failing over protocol=h3 After kill cloudd + nsurlsessiond: immediate flush via protocol=http/1.1 An automated evidence-collection script (collect_h3_deadlock_evidence.sh) captures paired before-kill / after-kill logs. Included in the Feedback report. Symptom Check (for others hitting this) /usr/bin/log show --predicate 'process == "cloudd"' --last 5m 2>&1 \ | grep "putContainer.*err=T.*requestDuration=-1.000.*protocol=h3" | wc -l Output > 0 = this deadlock. Output = 0 = different issue. Recovery (one-liner) kill $(ps -axo user,pid,command | awk -v u="$USER" \ '($1==u && /CloudKitDaemon.framework.*cloudd/ && !/--system/) \ || ($1==u && /\/usr\/libexec\/nsurlsessiond/ && !/--privileged/) \ {print $2}') Both daemons respawn within 1–2 seconds. Do not use killall nsurlsessiond — it would also kill the privileged system instance. What was ruled out Network connectivity (Photos uploaded 8 MB through the same pool simultaneously) iCloud account (metadata operations succeeding, only body uploads failing) File type/content (random data, correlation is with size, not type) Storage quota (1.65 TB free) CFNetworkHTTP3Enabled=false (key is ineffective in 26.4.1) Suggested fixes (from the Feedback report) CFNetwork: Invalidate the QUIC session after N consecutive requestDuration=-1.000 failures CloudKit/NSURLSession: Expose a pool invalidation API like [NSURLSession invalidatePoolEntryForEndpoint:] cloudd: Self-healing retry — create a fresh NSURLSession after M consecutive deadlock-signature failures Finder: At minimum, surface the stuck state to the user instead of failing silently Filed as FB22476701 — includes full reproduction timelines, request/connection UUIDs, sysdiagnose, and a 12-page investigation PDF with architecture diagrams and protocol comparison tables. If you're experiencing the same issue, please file a duplicate referencing FB22476701 — Apple prioritizes by duplicate count. System MacBook Air, macOS 26.4.1 (25E253) iCloud Drive with Desktop & Documents sync en0 (WLAN) + en5 (USB-LAN via Studio Display)
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Apr ’26