CoreData to SwiftData Persistence Migration Plan

Role: Senior Apple Platform Storage Architect with deep expertise in SQLite, Core Data migration pipelines, and SwiftData schemas.

Context

• Client app: {{client_app_name}}
• Current persistence architecture: {{current_persistence_framework}}
• Relational model complexity: {{entity_relationship_complexity}}
• CloudKit integration requirement: {{cloudkit_sync_requirement}}
• Database migration risk level: {{database_migration_risk_level}}
• Deployment target: iOS {{minimum_os_deployment_target}}

Task

Author an end-to-end persistence migration plan for {{client_app_name}} to transition from {{current_persistence_framework}} to SwiftData, handling {{entity_relationship_complexity}} while guaranteeing zero data loss under {{database_migration_risk_level}} conditions on iOS {{minimum_os_deployment_target}}.

Method

1. Audit the existing .xcdatamodeld configuration and map NSManagedObject classes directly to SwiftData @Model equivalents.
2. Review schema relationships and evaluate constraints against {{cloudkit_sync_requirement}} compatibility rules.
3. Design a staged migration plan managing SQLite store compatibility without corrupting existing user databases.
4. Define SchemaMigrationPlan stages including custom migration stages for non-trivial transformations.
5. Outline the transition strategy from NSFetchedResultsController to SwiftUI @Query macro bindings.
6. Formulate background processing and batch mutation strategies using ModelActor and dedicated background ModelContext instances.
7. Detail automated validation tests verifying SQLite store integrity and CloudKit record synchronization.

Constraints

• MUST guarantee fallback and rollback integrity with zero database corruption on schema failure.
• MUST NOT break CloudKit schema compatibility if {{cloudkit_sync_requirement}} is active.
• MUST validate that all @Model class relationships maintain explicit deletion rules.
• Background operations MUST execute on dedicated ModelActor instances.

Output format

Generate a structured engineering plan containing:

1. Schema Translation Specification (entity and relationship mapping)
2. Staged Migration and Schema Evolution Strategy (handling {{database_migration_risk_level}})
3. Concurrency & Query Architecture (ModelActor and SwiftUI @Query guidelines)
4. Rollback and Verification Runbook (data integrity verification steps)

Self-review

• Ensure all variables ({{client_app_name}}, {{current_persistence_framework}}, {{entity_relationship_complexity}}, {{cloudkit_sync_requirement}}, {{database_migration_risk_level}}, {{minimum_os_deployment_target}}) are integrated.
• Confirm that custom migration stages are addressed if complex transformations exist.
• Verify that the four required output sections match the explicit schema contract.