- name
- swiftdata-code-review
- description
- Reviews SwiftData code for model design, queries, concurrency, and migrations. Use when reviewing .swift files with import SwiftData, @Model, @Query, @ModelActor, or VersionedSchema.
SwiftData Code Review
Quick Reference
| Issue Type | Reference |
|---|---|
| @Model, @Attribute, @Relationship, delete rules | references/model-design.md |
| @Query, #Predicate, FetchDescriptor, #Index | references/queries.md |
| @ModelActor, ModelContext, background operations | references/concurrency.md |
| VersionedSchema, MigrationStage, lightweight/custom | references/migrations.md |
Hard gates (before reporting findings)
Run in order; do not assert an issue until the gate for that issue passes.
- Scope — pass when: You have the target
.swiftpath(s) and confirmed SwiftData surface in scope (e.g.import SwiftData,@Model,@Query,@ModelActor,VersionedSchema, or migration types). If none apply, stop or narrow scope with one sentence. - Reference — pass when: For each checklist area you evaluate (models, queries, concurrency, migrations), you opened the matching
references/*.mdfrom the Quick Reference table or wroteN/A: no <area> in this reviewwith a one-line reason. - Evidence — pass when: Every finding uses the
[FILE:LINE] ISSUE_TITLEheader (line range allowed) from the file you read; no finding without a cite. - Report — pass when: Findings list cites first (or inline) using
[FILE:LINE] ISSUE_TITLE, then severity or checklist grouping—no uncited assertions.
Review Checklist
- [ ] Models marked
final(subclassing crashes) - [ ] @Relationship decorator on ONE side only (not both)
- [ ] Delete rules explicitly set (not relying on default .nullify)
- [ ] Relationships initialized to empty arrays, not default objects
- [ ] Batch operations used for bulk inserts (
append(contentsOf:)) - [ ] @Query not loading thousands of items on main thread
- [ ] External values in predicates captured in local variables
- [ ] Scalar comparisons in predicates (not object references)
- [ ] @ModelActor used for background operations
- [ ] PersistentIdentifier/DTOs used to pass data between actors
- [ ] VersionedSchema defined for each shipped version
- [ ] MigrationPlan passed to ModelContainer
When to Load References
- Reviewing @Model or relationships -> model-design.md
- Reviewing @Query or #Predicate -> queries.md
- Reviewing @ModelActor or background work -> concurrency.md
- Reviewing schema changes or migrations -> migrations.md
Review Questions
- Could this relationship assignment cause NULL foreign keys?
- Is @Relationship on both sides creating circular references?
- Could this @Query block the main thread with large datasets?
- Are model objects being passed between actors unsafely?
- Would schema changes require a migration plan?