The stuff I've found by searching has confused me, so hopefully someone can help simplify it for me? I have an app (I use it for logging which books I've given away), and I could either add a bunch of things to the app, or I could have another app (possibly a CLI tool) to generate some reports I'd like.

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.

I’m trying to build a CRUD app using SwiftData, @Query model and multidatepicker. The data from a multidatepicker is stored or persists in SwiftData as Set = []. My current dilemma is how to use SwiftData and @Query model Predicate to find all records on the current date. I can’t find any SwiftData documentation or examples @Query using Set = []. My CRUD app should retrieve all records for the current date. Unfortunately, I don’t know the correct @Query model syntax for Set = [].

What have people's experience with converting locally stored app data to a more browser based accessible format? Firebase seems expensive, Subabase a bit more challenging, and CloudKit too restrictive.

I have developed an podcast app, where subscriped podcast & episodes synched with iCloud. So its working fine with iOS & iPad with latest os version, but iCloud not synching in iPod with version 15. Please help me to fix this. Thanks Devendra K.

Hello, I am building a pretty large database (~40MB) to be used in my SwiftData iOS app as read-only. While inserting and updating the data, I noticed a substantial increase in size (+ ~10MB). A little digging pointed to ACHANGE and ATRANSACTION tables that apparently are dealing with Persistent History Tracking. While I do appreciate the benefits of that, I prefer to save space. Could you please point me in the right direction?

Hello, thank you Apple for supporting custom store with SwiftData and the Schema type is superb to work with. I have successfully set one up with SQL and have some feedback and issues regarding its APIs. There’s a highlighted message in the documentation about not using internal restricted symbols directly, but they contradict with the given protocols and I am concerned about breaking any App Store rules. Are we allowed to use these? If not, they should be opened up as they’re useful. BackingData is required to set up custom snapshots, initialization, and getting/setting values. And I want to use it with createBackingData() to directly initialize instances from snapshots when transferring them between server and client or concurrency. RelationshipCollection for casting to-many relationships from backing data or checking if an array contains a PersistentModel. SchemaProperty for type erasure in a collection. Schema.Relationship has KeyPath properties, but it is missing for Schema.Attribute and Schema.CompositeAttribute. Which means you can’t purely depend on the schema to map data. I am unable to access the properties of a custom struct type in a predicate unless I use Mirror with schemaMetadata() or CustomStringConvertible on the KeyPath directly to extract it. Trivial, but… the KeyPath property name is inconsistent (it’s all lowercase). It would be nice to retrieve property names from custom struct types, since you are unable access CodingKeys that are auto synthesized by Codable for structs. But I recently realized they’re a part Schema.CompositeAttribute, however I don’t know how to match these without the KeyPath… I currently map my entities using CodingKeys to their PredicateCodableKeyPathProviding.… but I wish for a simpler alternative! It’s unclear how to provide the schema to the snapshot before new models are created. I currently use a static property, but I want to make it flexible if more schemas and configurations are added later on. I considered saving and loading the schema in a temporary location, but doubtful that the KeyPath values will be available as they are not Codable. I suspect schemaMetadata() has the information I need to map the backing data without a schema for snapshots, but as mentioned previously, properties are inaccessible… Allow access to entity metatypes, like value types from SchemaProperty. They’re useful for getting data out of snapshots and casting them to CodingKeys and PredicateCodableKeyPathProviding. They do not carry over when you provide them in the Schema. I am unable to retrieve the primary key from PersistentIdentifier. It seems like once you create one, you can’t get it out, like the DataStoreConfiguration in ModelContainer is not the one you used to set it up. I cannot cast it, it is an entirely different struct? I have to use JSONSerialization to extract it, but I want to get it directly since it is not a column in my database. It is transformed when it goes to/from my tables. It’s unknown how to support some schema options, such as Spotlight and CloudKit. Allow for extending macro options, such as adding options to set as primary key, whether to auto increment, etc… You can create a schema for super and sub entities, but it doesn’t appear you can actually set them up from the @Model macro or use inheritance on these models… SwiftData history tracking seems incomplete for HistoryDelete, because that protocol requires HistoryTombstone, but this type cannot be instantiated, nor does it contain anything useful to infer from. As an aside, I want to create my own custom ModelActor that is a global actor. However, I’m unable to replicate the executor that Apple provides where the executor has a ModelContext, because this type does not conform to Sendable. So how did Apple do this? The documentation doesn’t mention unchecked Sendable, but I figure if the protocol is available then we would be able to set up our own. And please add concurrency features! Anyway, I hope for more continued support in the future and I am looking forward to what’s new this WWDC! 😊

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

Starting 20th March 2025, I see an increase in bandwidth and latency for one of my CloudKit projects. I'm using NSPersistentCloudKitContainer to synchronise my data. I haven't changed any CloudKit scheme during that time but shipped an update. Since then, I reverted some changes from that update, which could have led to changes in the sync behaviour. Is anyone else seeing any issues? I would love to file a DTS and use one of my credits for that, but unfortunately, I can't because I cannot reproduce it with a demo project because I cannot travel back in time and check if it also has an increase in metrics during that time. Maybe an Apple engineer can green-light me filing a DTS request, please.

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.

Apple's iCloud File Management documentation says to "avoid special punctuation or other special characters" in filenames, but doesn't specify which characters. I need a definitive list to implement filename sanitization in my shipping app. Confirmed issues Our iOS app (CyberTuner, App Store, 15 years shipping on App Store) manages .rcta files in the iCloud ubiquity container via NSFileManager APIs. We've confirmed two characters causing sync failures: Ampersand (&): A file named Yamaha CP70 & CP80.rcta caused repeated "couldn't be backed up" dialogs. ~12 users reported this independently. Replacing & resolved it immediately. No other files in the same directory were affected. Percent (%): A file with % in the filename was duplicated by iCloud sync (e.g., filename% 1.rcta, filename% 2.rcta), and the original was lost. Currently reproducing across multiple devices. Both characters have special meaning in URL encoding (% is the escape character, & is the query parameter separator), which suggests the issue may be in URL handling within the sync pipeline. What I'm looking for: A definitive list of characters that cause problems in the iCloud sync pipeline specifically — not APFS restrictions, but CloudDocs/FileProvider/server-side issues. Confirmation whether these characters are problematic: & % # ? + / : * " < > | Is there a system API for validating or sanitizing filenames for iCloud compatibility before writing to the ubiquity container? Our users are piano technicians who naturally name files "Steinway & Sons" — we need to know exactly what to sanitize rather than guessing. Environment: iOS 17–26, Xcode 26.1, APFS, NSFileManager ubiquity container APIs Bundle FEEDBACK ASSISTANT ID FB21900837

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?

Hello everyone, I am experiencing a persistent authentication error when querying a custom user profile record, and the error message seems to be a red herring. My Setup: I have a custom CKRecord type called ColaboradorProfile. When a new user signs up, I create this record and store their hashed password, salt, nickname, and a custom field called loginIdentifier (which is just their lowercase username). In the CloudKit Dashboard, I have manually added an index for loginIdentifier and set it to Queryable and Searchable. I have deployed this schema to Production. The Problem: During login, I run an async function to find the user's profile using this indexed loginIdentifier. Here is the relevant authentication code: func autenticar() async { // ... setup code (isLoading, etc.) let lowercasedUsername = username.lowercased() // My predicate ONLY filters on 'loginIdentifier' let predicate = NSPredicate(format: "loginIdentifier == %@", lowercasedUsername) let query = CKQuery(recordType: "ColaboradorProfile", predicate: predicate) // I only need these specific keys let desiredKeys = ["password", "passwordSalt", "nickname", "isAdmin", "isSubAdmin", "username"] let database = CKContainer.default().publicCloudDatabase do { // This is the line that throws the error let result = try await database.records(matching: query, desiredKeys: desiredKeys, resultsLimit: 1) // ... (rest of the password verification logic) } catch { // The error always lands here logDebug("Error authenticating with CloudKit: \(error.localizedDescription)") await MainActor.run { self.errorMessage = "Connection Error: \(error.localizedDescription)" self.isLoading = false self.showAlert = true } } } The Error: Even though my query predicate only references loginIdentifier, the catch block consistently reports this error: Error authenticating with CloudKit: Field 'createdBy' is not marked queryable. I know createdBy (the system creatorUserRecordID) is not queryable by default, but my query isn't touching that field. I already tried indexing createdBy just in case, but the error persists. It seems CloudKit cannot find or use my index for loginIdentifier and is incorrectly reporting a fallback error related to a system field. Has anyone seen this behavior? Why would CloudKit report an error about createdBy when the query is explicitly on an indexed, custom field? I'm new to Swift and I'm struggling quite a bit. Thank you,

In a document based SwiftData app for macOS, how do you go about opening a (modal) child window connected to the ModelContainer of the currently open document? Using .sheet() does not really result in a good UX, as the appearing view lacks the standard window toolbar. Using a separate WindowGroup with an argument would achieve the desired UX. However, as WindowGroup arguments need to be Hashable and Codable, there is no way to pass a ModelContainer or a ModelContext there: WindowGroup(id: "myWindowGroup", for: MyWindowGroupArguments.self) { $args in ViewThatOpensInAWindow(args: args) } Is there any other way?

Hi everyone, Im trying to set up CloudKit for my Unreal Engine 5.4 project but seem to be hitting some roadblocks on how to set up the Record Types. From my understanding I need to set up a "file" record type with a "contents" asset field - but even with this it doesn't seem to work :( Any unreal engine devs with some experience on this who could help me out? Thanks!

Greetings i have an app that uses three different SwiftData models and i want to know what is the best way to use the them accross the app. I though a centralized behaviour and i want to know if it a correct approach.First let's suppose that the first view of the app will load the three models using the @Enviroment that work with @Observation. Then to other views that add data to the swiftModels again with the @Environment. Another View that will use the swiftData models with graph and datas for average and min and max.Is this a corrent way? or i should use @Query in every view that i want and ModelContext when i add the data. @Observable class CentralizedDataModels { var firstDataModel: [FirstDataModel] = [] var secondDataModel: [SecondDataModel] = [] var thirdDataModel: [ThirdDataModel] = [] let context: ModelContext init(context:ModelContext) { self.context = context } }

The NSMetadataUbiquitousItemDownloadingStatusKey indicates the status of a ubiquitous (iCloud Drive) file. A key value of NSMetadataUbiquitousItemDownloadingStatusDownloaded is defined as indicating there is a local version of this file available. The most current version will get downloaded as soon as possible . However this no longer occurs since iOS 18.4. A ubiquitous file may remain in the NSMetadataUbiquitousItemDownloadingStatusDownloaded state for an indefinite period. There is a workaround: call [NSFileManager startDownloadingUbiquitousItemAtURL: error:] however this shouldn't be necessary, and introduces delays over the previous behaviour. Has anyone else seen this behaviour? Is this a permanent change? FB17662379

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!

In core-data I have a contact and location entity. I have one-to-many relationship from contact to locations and one-to-one from location to contact. I create contact in a seperate view and save it. Later I create a location, fetch the created contact, and save it while specifying the relationship between location and contact contact and test if it actually did it and it works. viewContext.perform { do { // Set relationship using the generated accessor method currentContact.addToLocations(location) try viewContext.save() print("Saved successfully. Locations count:", currentContact.locations?.count ?? 0) if let locs = currentContact.locations { print("📍 Contact has \(locs.count) locations.") for loc in locs { print("➡️ Location: \(String(describing: (loc as AnyObject).locationName ?? "Unnamed"))") } } } catch { print("Failed to save location: \(error.localizedDescription)") } } In my NSManagedObject class properties I have this : for Contact: @NSManaged public var locations: NSSet? for Location: @NSManaged public var contact: Contact? in my persistenceController I have: for desc in [publicStore, privateStore] { desc.setOption(true as NSNumber, forKey: NSPersistentStoreRemoteChangeNotificationPostOptionKey) desc.setOption(true as NSNumber, forKey: NSPersistentHistoryTrackingKey) desc.setOption(true as NSNumber, forKey: NSMigratePersistentStoresAutomaticallyOption) desc.setOption(true as NSNumber, forKey: NSInferMappingModelAutomaticallyOption) desc.setOption(true as NSNumber, forKey: "CKSyncCoreDataDebug") // Optional: Debug sync // Add these critical options for relationship sync desc.setOption(true as NSNumber, forKey: "NSPersistentStoreCloudKitEnforceRecordExistsKey") desc.setOption(true as NSNumber, forKey: "NSPersistentStoreCloudKitMaintainReferentialIntegrityKey") // Add this specific option to force schema update desc.setOption(true as NSNumber, forKey: "NSPersistentStoreRemoteStoreUseCloudKitSchemaKey") } When synchronization happens on CloudKit side, it creates CKRecords: CD_Contact and CD_Location. However for CD_Location it creates the relationship CD_contact as a string and references the CD_Contact. This I thought should have come as REFERENCE On the CD_Contact there is no CD_locations field at all. I do see the relationships being printed on coredata side but it does not come as REFERENCE on cloudkit. Spent over a day on this. Is this normal, what am I doing wrong here? Can someone advise?

I have a CoreData model with two configuration - but several problems. Notably the viewContext only shows data from the .private configuration. Here is the setup: The private configuration holds entities, for example, User and Course and the shared one holds entities, for example, Player and League. I setup the NSPersistentStoreDescriptions to use the same container but with a databaseScope of .private/.shared and with the configuration of "Private"/"Shared". loadPersistentStores() does not report an error. If I try container.initializeCloudKitSchema() only the .private configuration produces CKRecord types. If I create a companion app using one configuration (w/ all entities) the schema initialization creates all CKRecord types AND I can populate some data in the .private and a created CKShare. I see that data in the CloudKit dashboard. If I axe the companion app and run the real thing w/ two configurations, the viewContext only has the .private data. Why? If when querying history I use NSPersistentHistoryTransaction.fetchRequest I get a nil return when using two configurations (but non-nil when using one).