CloudKit Code Review

Quick Reference

Issue Type Reference

CKContainer, databases, zones, entitlements references/container-setup.md

CKRecord, references, assets, batch operations references/records.md

CKSubscription, push notifications, silent sync references/subscriptions.md

CKShare, participants, permissions, acceptance references/sharing.md

Review Checklist

• Account status checked before private/shared database operations

• Custom zones used (not default zone) for production data

• All CloudKit errors handled with retryAfterSeconds respected

• serverRecordChanged conflicts handled with proper merge logic

• CKErrorPartialFailure parsed for individual record errors

• Batch operations used (CKModifyRecordsOperation ) not individual saves

• Large binary data stored as CKAsset (records have 1MB limit)

• Record keys type-safe (enums) not string literals

• UI updates dispatched to main thread from callbacks

• CKAccountChangedNotification observed for account switches

• Subscriptions have unique IDs to prevent duplicates

• CKShare uses custom zone (sharing requires custom zones)

When to Load References

• Reviewing container/database setup or zones -> container-setup.md

• Reviewing record CRUD or relationships -> records.md

• Reviewing push notifications or sync triggers -> subscriptions.md

• Reviewing sharing or collaboration features -> sharing.md

Output Format

Report issues using: [FILE:LINE] ISSUE_TITLE

Examples:

• [AppDelegate.swift:24] CKContainer not in custom zone

• [SyncManager.swift:156] Unhandled CKErrorPartialFailure

• [DataStore.swift:89] Missing retryAfterSeconds backoff

Review Questions

• What happens when the user is signed out of iCloud?

• Does error handling respect rate limiting (retryAfterSeconds )?

• Are conflicts resolved or does data get overwritten silently?

• Is the schema deployed to production before App Store release?

• Are shared records in custom zones (required for CKShare)?