axiom-data
axiom-data equips AI coding assistants with production-grade database expertise for Apple ecosystem development. Navigate persistence patterns, framework selection, and data architecture decisions with confidence—avoiding common pitfalls that lead to performance issues and data integrity problems. Built for Swift 6, SwiftUI, and modern Apple Intelligence workflows.
axiom-data guides you through SwiftData integration from setup to production. Start by defining your models with @Model macros, configure your ModelContainer at app launch, and use @Query in SwiftUI views for reactive data binding. axiom-data covers threading best practices, background context handling, and common pitfalls like N+1 queries that degrade performance on tvOS and other platforms.
AI-generated summary based on this skill's SKILL.md
Install
CharlesWiltgen/Axiom/axiom-data · repository language: Go
git clone https://github.com/CharlesWiltgen/Axiom
cp -r Axiom/axiom-codex/skills/axiom-data ~/.claude/skills/axiom-dataFrequently asked questions
AI-generated answers based on this skill's SKILL.md and metadata
How to use SwiftData in my app?
axiom-data guides you through SwiftData integration from setup to production. Start by defining your models with @Model macros, configure your ModelContainer at app launch, and use @Query in SwiftUI views for reactive data binding. axiom-data covers threading best practices, background context handling, and common pitfalls like N+1 queries that degrade performance on tvOS and other platforms.
Core Data vs SwiftData—which should I use?
axiom-data helps you choose the right framework for your needs. SwiftData is Apple's modern, Swift-native alternative with simpler syntax and built-in CloudKit sync; Core Data offers deeper control and broader iOS version support. axiom-data breaks down trade-offs: SwiftData excels for new projects targeting iOS 17+, while Core Data remains essential for legacy apps or complex multi-store architectures.
How do I safely add a column to a SwiftData model?
axiom-data provides migration patterns to add columns without data loss. Update your @Model definition with the new property, then use VersionedSchema and MigrationPlan to define the schema version and migration logic. axiom-data emphasizes testing migrations in staging first, using lightweight migrations when possible, and validating data integrity before deploying to production.
What database schema migration safety practices does axiom-data cover?
axiom-data teaches defensive migration strategies: version your schemas explicitly, test migrations with production-like data volumes, use lightweight migrations for simple changes, and implement rollback procedures. It covers both SwiftData and Core Data approaches, including handling edge cases like concurrent migrations and ensuring CloudKit sync consistency during schema evolution.
How do I set up cloud sync and offline-first data persistence?
axiom-data explains modern sync architectures combining SwiftData's CloudKit integration with offline-first patterns. Configure CloudKit containers, handle sync conflicts gracefully, and implement local-first writes with background sync. axiom-data covers detecting connectivity, queuing changes offline, and reconciling state when the device reconnects—critical for widget apps and tvOS environments.
How should I securely store sensitive data like tokens?
axiom-data recommends Keychain for tokens and secrets, never storing them in SwiftData or Core Data. Use CryptoKit for encryption when needed, handle errSecDuplicateItem errors gracefully, and follow best practices for credential lifecycle management. axiom-data also covers secure serialization with Codable, avoiding common mistakes like logging sensitive values or persisting them to iCloud Drive.
SKILL.md
rendered from the published skill — quoted content, verbatim
Data & Persistence
You MUST use this skill for ANY data persistence, database, storage, CloudKit, or serialization work.
<!-- AXIOM_AUDITOR_INLINE_BEGIN — auto-maintained by scripts/build-inlined-auditors.ts; do not hand-edit -->
> Not on Claude Code? Where this router says "Launch some-auditor agent", read that auditor's file in this suite and follow it inline — the same procedure, needing only file search and read.
>
> Available here: skills/codable-auditor.md, skills/core-data-auditor.md, skills/database-schema-auditor.md, skills/grdb-performance-auditor.md, skills/icloud-auditor.md, skills/storage-auditor.md, skills/swiftdata-auditor.md.
>
> Agents that need Bash — builds, tests, simulators, crash symbolication — stay Claude Code-only; there is no inline equivalent for those.
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When to Use
Use this skill when working with: - Databases (SwiftData, Core Data, GRDB,
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File tree — 15 files
axiom-codex/skills/axiom-data/SKILL.md
axiom-codex/skills/axiom-data/agents/openai.yaml
axiom-codex/skills/axiom-data/skills/cloud-sync-diag.md
axiom-codex/skills/axiom-data/skills/cloud-sync.md
axiom-codex/skills/axiom-data/skills/cloudkit-ref.md
axiom-codex/skills/axiom-data/skills/codable.md
axiom-codex/skills/axiom-data/skills/core-data-diag.md
axiom-codex/skills/axiom-data/skills/core-data.md
axiom-codex/skills/axiom-data/skills/database-migration.md
axiom-codex/skills/axiom-data/skills/grdb-app-groups.md
axiom-codex/skills/axiom-data/skills/grdb-performance.md
axiom-codex/skills/axiom-data/skills/grdb.md
axiom-codex/skills/axiom-data/skills/icloud-drive-ref.md
axiom-codex/skills/axiom-data/skills/realm-migration-ref.md
axiom-codex/skills/axiom-data/skills/sql-json-ref.md