core-data-expert

Name: core-data-expert
Author: AvdLee

2.0kinstalls16forks

How to install core-data-expert?

avdlee/core-data-agent-skill/core-data-expert

$npx -y skills add AvdLee/Core-Data-Agent-Skill --skill core-data-expert

Installs into the current project.

Summary

Expert Core Data guidance (iOS/macOS): stack setup, fetch requests & NSFetchedResultsController, saving/merge conflicts, threading & Swift Concurrency, batch operations & persistent history, migrations, performance, and NSPersistentCloudKitContainer/CloudKit sync.

Files · 1

View on GitHub

SKILL.md

1	# Core Data Expert
2
3	Fast, production-oriented guidance for building correct, performant Core Data stacks and fixing common crashes.
4
5	## Agent behavior contract (follow these rules)
6
7	1. Determine OS/deployment target when advice depends on availability (iOS 14+/17+ features, etc.).
8	2. Identify the context type before proposing fixes: view context (UI) vs background context (heavy work).
9	3. Recommend `NSManagedObjectID` for cross-context/cross-task communication; never pass `NSManagedObject` instances across contexts.
10	4. Prefer lightweight migration when possible; use staged migration (iOS 17+) for complex changes.
11	5. When recommending batch operations, verify persistent history tracking is enabled (often required for UI updates).
12	6. For CloudKit integration, remind developers that Production schema is immutable.
13	7. Reference WWDC/external resources sparingly; prefer this skill’s `references/`.
14
15	## First 60 seconds (triage template)
16
17	- Clarify the goal: setup, bugfix, migration, performance, CloudKit?
18	- Collect minimal facts:
19	- platform + deployment target
20	- store type (SQLite / in-memory) and whether CloudKit is enabled
21	- context involved (view vs background) and whether Swift Concurrency is in use
22	- exact error message + stack trace/logs
23	- Branch immediately:
24	- threading/crash → focus on context confinement + `NSManagedObjectID` handoff
25	- migration error → identify model versions + migration strategy
26	- batch ops not updating UI → persistent history tracking + merge pipeline
27
28	## Routing map (pick the right reference fast)
29
30	- Stack setup / merge policies / contexts → `references/stack-setup.md`
31	- Saving patterns → `references/saving.md`
32	- Fetch requests / list updates / aggregates → `references/fetch-requests.md`
33	- Traditional threading (perform/performAndWait, object IDs) → `references/threading.md`
34	- Swift Concurrency (async/await, actors, Sendable, DAOs) → `references/concurrency.md`
35	- Batch insert/delete/update → `references/batch-operations.md`
36	- Persistent history tracking + “batch ops not updating UI” → `references/persistent-history.md`
37	- Model configuration (constraints, validation, derived/composite, transformables) → `references/model-configuration.md`
38	- Schema migration (lightweight/staged/deferred) → `references/migration.md`
39	- CloudKit integration & debugging → `references/cloudkit-integration.md`
40	- Performance profiling & memory → `references/performance.md`
41	- Testing patterns → `references/testing.md`
42	- Terminology → `references/glossary.md`
43
44	## Common errors → next best move
45
46	- “Failed to find a unique match for an NSEntityDescription” → `references/testing.md` (shared `NSManagedObjectModel`)
47	- `NSPersistentStoreIncompatibleVersionHashError` → `references/migration.md` (versioning + migration)
48	- Cross-context/threading exceptions (e.g. delete/update from wrong context) → `references/threading.md` and/or `references/concurrency.md` (use `NSManagedObjectID`)
49	- Sendable / actor-isolation warnings around Core Data → `references/concurrency.md` (don’t “paper over” with `@unchecked Sendable`)
50	- `NSMergeConflict` / constraint violations → `references/model-configuration.md` + `references/stack-setup.md` (constraints + merge policy)
51	- Batch operations not updating UI → `references/persistent-history.md` + `references/batch-operations.md`
52	- CloudKit schema/sync issues → `references/cloudkit-integration.md`
53	- Memory grows during fetch → `references/performance.md` + `references/fetch-requests.md`
54
55	## Verification checklist (when changing Core Data code)
56
57	- Confirm the context matches the work (UI vs background).
58	- Ensure `NSManagedObject` instances never cross contexts; pass `NSManagedObjectID` instead.
59	- If using batch ops, confirm persistent history tracking + merge pipeline.
60	- If using constraints, confirm merge policy and conflict resolution strategy.
61	- If performance-related, profile with Instruments and validate fetch batching/limits.
62
63	## Reference files
64
65	- `references/_index.md` (navigation)
66	- `references/stack-setup.md`
67	- `references/saving.md`
68	- `references/fetch-requests.md`
69	- `references/threading.md`
70	- `references/concurrency.md`
71	- `references/batch-operations.md`
72	- `references/persistent-history.md`
73	- `references/model-configuration.md`
74	- `references/migration.md`
75	- `references/cloudkit-integration.md`
76	- `references/performance.md`
77	- `references/testing.md`
78	- `references/glossary.md`

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core-data-expert

2.0kinstalls16forks

View on GitHub

How to install core-data-expert?

avdlee/core-data-agent-skill/core-data-expert

$npx -y skills add AvdLee/Core-Data-Agent-Skill --skill core-data-expert

Installs into the current project.

Summary

Files · 1

View on GitHub

SKILL.md

1	# Core Data Expert
2
3	Fast, production-oriented guidance for building correct, performant Core Data stacks and fixing common crashes.
4
5	## Agent behavior contract (follow these rules)
6
7	1. Determine OS/deployment target when advice depends on availability (iOS 14+/17+ features, etc.).
8	2. Identify the context type before proposing fixes: view context (UI) vs background context (heavy work).
9	3. Recommend `NSManagedObjectID` for cross-context/cross-task communication; never pass `NSManagedObject` instances across contexts.
10	4. Prefer lightweight migration when possible; use staged migration (iOS 17+) for complex changes.
11	5. When recommending batch operations, verify persistent history tracking is enabled (often required for UI updates).
12	6. For CloudKit integration, remind developers that Production schema is immutable.
13	7. Reference WWDC/external resources sparingly; prefer this skill’s `references/`.
14
15	## First 60 seconds (triage template)
16
17	- Clarify the goal: setup, bugfix, migration, performance, CloudKit?
18	- Collect minimal facts:
19	- platform + deployment target
20	- store type (SQLite / in-memory) and whether CloudKit is enabled
21	- context involved (view vs background) and whether Swift Concurrency is in use
22	- exact error message + stack trace/logs
23	- Branch immediately:
24	- threading/crash → focus on context confinement + `NSManagedObjectID` handoff
25	- migration error → identify model versions + migration strategy
26	- batch ops not updating UI → persistent history tracking + merge pipeline
27
28	## Routing map (pick the right reference fast)
29
30	- Stack setup / merge policies / contexts → `references/stack-setup.md`
31	- Saving patterns → `references/saving.md`
32	- Fetch requests / list updates / aggregates → `references/fetch-requests.md`
33	- Traditional threading (perform/performAndWait, object IDs) → `references/threading.md`
34	- Swift Concurrency (async/await, actors, Sendable, DAOs) → `references/concurrency.md`
35	- Batch insert/delete/update → `references/batch-operations.md`
36	- Persistent history tracking + “batch ops not updating UI” → `references/persistent-history.md`
37	- Model configuration (constraints, validation, derived/composite, transformables) → `references/model-configuration.md`
38	- Schema migration (lightweight/staged/deferred) → `references/migration.md`
39	- CloudKit integration & debugging → `references/cloudkit-integration.md`
40	- Performance profiling & memory → `references/performance.md`
41	- Testing patterns → `references/testing.md`
42	- Terminology → `references/glossary.md`
43
44	## Common errors → next best move
45
46	- “Failed to find a unique match for an NSEntityDescription” → `references/testing.md` (shared `NSManagedObjectModel`)
47	- `NSPersistentStoreIncompatibleVersionHashError` → `references/migration.md` (versioning + migration)
48	- Cross-context/threading exceptions (e.g. delete/update from wrong context) → `references/threading.md` and/or `references/concurrency.md` (use `NSManagedObjectID`)
49	- Sendable / actor-isolation warnings around Core Data → `references/concurrency.md` (don’t “paper over” with `@unchecked Sendable`)
50	- `NSMergeConflict` / constraint violations → `references/model-configuration.md` + `references/stack-setup.md` (constraints + merge policy)
51	- Batch operations not updating UI → `references/persistent-history.md` + `references/batch-operations.md`
52	- CloudKit schema/sync issues → `references/cloudkit-integration.md`
53	- Memory grows during fetch → `references/performance.md` + `references/fetch-requests.md`
54
55	## Verification checklist (when changing Core Data code)
56
57	- Confirm the context matches the work (UI vs background).
58	- Ensure `NSManagedObject` instances never cross contexts; pass `NSManagedObjectID` instead.
59	- If using batch ops, confirm persistent history tracking + merge pipeline.
60	- If using constraints, confirm merge policy and conflict resolution strategy.
61	- If performance-related, profile with Instruments and validate fetch batching/limits.
62
63	## Reference files
64
65	- `references/_index.md` (navigation)
66	- `references/stack-setup.md`
67	- `references/saving.md`
68	- `references/fetch-requests.md`
69	- `references/threading.md`
70	- `references/concurrency.md`
71	- `references/batch-operations.md`
72	- `references/persistent-history.md`
73	- `references/model-configuration.md`
74	- `references/migration.md`
75	- `references/cloudkit-integration.md`
76	- `references/performance.md`
77	- `references/testing.md`
78	- `references/glossary.md`

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Type