persistence-setup_skill

Overview

This skill generates a production-ready persistence layer for Swift apps using SwiftData (iOS 17+/macOS 14+) or CoreData, with optional iCloud (CloudKit) sync. It scaffolds container setup, repository patterns, optional example models, and CloudKit configuration so you can add local storage and device sync quickly. The output is tailored to your project’s target, existing persistence, and bundle identifier.

How this skill works

The skill first inspects the project for deployment target, existing SwiftData/CoreData usage, and iCloud entitlements to avoid conflicts. It then asks which framework to generate, whether to enable iCloud, and whether to include a sample model. Finally it writes a small set of files (container, repository, concrete implementations, optional models and CloudKit config) and adapts templates to project naming and bundle ID.

When to use it

• You want to add local data persistence to a Swift app
• You need a clean repository pattern and container setup for SwiftData or CoreData
• You plan to enable iCloud/CloudKit sync across user devices
• You are migrating from an older persistence layer to SwiftData
• You want example models and integration snippets for immediate use

Best practices

• Detect existing persistence first and choose extend, migrate, or create separately
• Prefer SwiftData for iOS 17+/macOS 14+ unless an existing CoreData stack requires keeping CoreData
• Make CloudKit container and entitlements match your app bundle before enabling iCloud
• Generate example models only to demonstrate patterns; adapt field names and relationships to your domain
• Verify modelContainer is applied at the app root and test persistence across launches and devices

Example use cases

• Scaffold a SwiftData-based persistence layer with a sample Item model for a todo app
• Add CoreData compatibility for apps targeting pre-iOS 17 while maintaining a repository interface
• Enable CloudKit sync for user data with entitlements and CloudKit container configuration
• Migrate a small CoreData model to SwiftData with repository wrappers for testing
• Provide a testable Repository protocol and concrete SwiftData repository for unit testing