SwiftData

Design persistence so model identity, relationships, query cost, migration, and context ownership remain explicit.

Contents

• Scope and Compatibility
• Workflow
• Models and Relationships
• Containers and Contexts
• Queries
• Migration and Coexistence
• Common Mistakes
• Review Checklist
• References

Scope and Compatibility

This skill owns @Model, ModelContainer, ModelContext, @Query, predicates, fetch descriptors, schema migration, @ModelActor, and SwiftData/CloudKit constraints. Route pure Core Data work to core-data, UI state wiring to swiftui-patterns, and general actor diagnostics to swift-concurrency.