Creator · CharlesWiltgen
Last updated · Sep 4, 2026
Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swift 6 concurrency, @MainActor, Sendable, data races, async/await patterns.
Creator · CharlesWiltgen
Last updated · Sep 4, 2026
Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swift 6 concurrency, @MainActor, Sendable, data races, async/await patterns.
Creator · CharlesWiltgen
Last updated · Sep 4, 2026
Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swift 6 concurrency, @MainActor, Sendable, data races, async/await patterns.
Creator · CharlesWiltgen
Last updated · Sep 4, 2026
Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swift 6 concurrency, @MainActor, Sendable, data races, async/await patterns.
Sandbox only
Install targets
Codex install prompt
Install the "axiom-concurrency" agent skill from https://github.com/CharlesWiltgen/Axiom/tree/main/.claude-plugin/plugins/axiom/skills/axiom-concurrency. Read its SKILL.md or equivalent instructions first, install only the files needed for this workspace, and summarize any required setup before using it. Skill purpose: Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swift 6 concurrency, @MainActor, Sendable, data races, async/await patterns. After the install attempt, report the result to https://www.openagentskill.com/api/agent/outcome with POST JSON {"event_id":"install_<unique-id>","skill_slug":"charleswiltgen-axiom-concurrency","task":"Install axiom-concurrency","agent":"codex","outcome":"success","install_used":true}. Replace event_id with a unique value and outcome with success or failed. Report success only after the skill is installed and a minimal verification passes.Supply asset profile
Code review, repo analysis, testing, CI, GitHub, DevOps, and developer workflow skills.
Scenario
GitHub automation
I need my agent to triage GitHub issues, review pull requests, and summarize repository changes.
Agent fit
Claude Code + CLI + Codex
Codex, Claude Code, Cursor, CLI, or custom agents.
Install
Ready
npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Maintenance
fresh
9d since push
Risk
Needs review
Dependency or permission surface needs review
GitHub quality
1.1K
78/100 Quality · 79/100 Trust
Coverage tags
Review notes
Dependency or permission surface needs review · Permission surface may require sandboxing
Agent adoption scorecard
These scores combine public repository metadata, OpenAgentSkill review signals, maintenance freshness, and install readiness. They are a shortlist signal, not a replacement for human review.
Quality
StrongSolid option that is likely worth shortlisting for production workflows.
Trust
Sandbox onlyUseful candidate with missing or mixed trust signals. Keep it in an isolated workspace until the outcome loop proves task fit.
Audit
Needs reviewA machine-readable review of install readiness, security metadata, maintenance, and adoption risk.
OpenAgentSkill Trust Score v5
Run only in a sandbox and compare close alternatives before using it for real work.
Stars
1.1K GitHub stars
Repo activity
1.1K stars, 83 forks
Maintenance
9d since push
License
MIT
Install
npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Install safety
Agent-readable metadata
Use this block or the embedded JSON to decide whether an agent should install this skill, choose an alternative, or ask for human review first.
Suited tasks
Suited agents
Install decision
Trust and risk
Outcome loop
Install command
npx skills add CharlesWiltgen/Axiom --skill axiom-concurrencyDo not use when
Agent safety v2
Sparse or mixed signals. Useful for discovery, but not for autonomous installation.
Test manually in an isolated workspace and compare against safer alternatives.
high
Skill metadata references terminal, CLI, shell, subprocess, or command execution workflows.
medium
Skill likely fetches remote pages, APIs, repositories, or external services.
medium
Skill may read or write project files, documents, generated artifacts, or local workspace state.
medium
Skill may inspect schemas, query databases, or work with persistent stores.
Agent resolve plan
The Resolve API returns the selected skill, alternatives, safety policy, audit notes, install target, and copy-paste prompt an agent can follow without scraping this page.
Open JSON
/api/agent/resolve?task=Use%20axiom-concurrency%20for%20an%20agent%20workflow&agent=codex&max_risk=medium
Resolve text
/api/agent/resolve?task=Use%20axiom-concurrency%20for%20an%20agent%20workflow&agent=codex&max_risk=medium&format=text
Install handoff
/api/skills/charleswiltgen-axiom-concurrency/install
Agent should check
Copy prompt
Task: Use axiom-concurrency in this workspace.
Resolve first: https://www.openagentskill.com/api/agent/resolve?task=Use%20axiom-concurrency%20for%20an%20agent%20workflow&agent=codex&max_risk=medium
Review install handoff: https://www.openagentskill.com/api/skills/charleswiltgen-axiom-concurrency/install
Install command: npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Before running it, summarize audit warnings, required permissions, and the fallback skill if install is risky.Agent handoff
Use the public install endpoint to fetch the command, safety checklist, target prompts, and canonical links for this skill.
Install handoff
/api/skills/charleswiltgen-axiom-concurrency/install
LLM text format
/api/skills/charleswiltgen-axiom-concurrency/install?format=text
Find alternatives
/api/skills/search?q=axiom-concurrency&limit=3
Agent prompt
Use axiom-concurrency for this task. Review https://www.openagentskill.com/api/skills/charleswiltgen-axiom-concurrency/install, then install with: npx skills add CharlesWiltgen/Axiom --skill axiom-concurrencyRegistry metadata
This page exposes the same decision, trust, audit, use-case, and install signals through the Registry API, so agents can rank this skill without scraping the UI.
Manifest
/api/registry/manifest/charleswiltgen-axiom-concurrency
LLM text
/api/registry/manifest/charleswiltgen-axiom-concurrency?format=text
Install alias
/api/registry/install/charleswiltgen-axiom-concurrency
Recommend
/api/registry/recommend?task=Use%20axiom-concurrency%20in%20an%20agent%20workflow&limit=3
Agent fit
RAG and knowledge
Platforms
Claude Code
Audit report
A machine-readable review of install readiness, security metadata, maintenance, and adoption risk.
Agent decision cockpit
Use this as a leading candidate, then validate the README and install path in your own agent stack.
Role in stack
Primary pick
Primary fit
RAG and knowledge
Trust label
Production-ready
Install path
Command ready
Use when
Evidence
review first
Implementation path
Trust profile
Useful candidate with missing or mixed trust signals. Keep it in an isolated workspace until the outcome loop proves task fit.
GitHub adoption
PASS1.1K GitHub stars
Stars/forks activity
INFO1.1K stars, 83 forks; issue activity unavailable in current metadata
Recent maintenance
PASS9d since push
License clarity
PASSMIT
Good signals
Review before install
Recommended action
Run only in a sandbox and compare close alternatives before using it for real work.
Quality profile
Solid option that is likely worth shortlisting for production workflows.
Workflow fit
Search private knowledge
I need my agent to build a RAG workflow over documents and retrieve reliable context.
Operate web apps
I need my agent to control a browser, fill forms, and verify web app workflows.
Automate repeated work
I need my agent to automate a repeated workflow across tools and files.
Workflow fit
Operate and verify web apps
A workflow for agents that navigate products, fill forms, take screenshots, and verify real user flows across web applications.
Turn skills into distribution
A workflow for turning newly indexed skills into SEO briefs, social drafts, comparison pages, and reusable publishing workflows.
Ingest, retrieve, and cite
A workflow for document-heavy agents that ingest files, create searchable knowledge, retrieve relevant context, and answer with grounded sources.
Alternative shortlist
Similar skills that may fit this task.
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--- name: axiom-concurrency description: Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swift 6 concurrency, @MainActor, Sendable, data races, async/await patterns. license: MIT ---
# Concurrency
**You MUST use this skill for ANY concurrency, async/await, threading, or Swift 6 concurrency 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/concurrency-auditor.md`. > > Agents that need Bash — builds, tests, simulators, crash symbolication — stay Claude Code-only; there is no inline equivalent for those. <!-- AXIOM_AUDITOR_INLINE_END -->
## Quick Reference
| Symptom / Task | Reference | |----------------|-----------| | async/await patterns, @MainActor, actors | See `skills/swift-concurrency.md` | | Data race errors, Sendable conformance | See `skills/swift-concurrency.md` | | Swift 6 migration, @concurrent attribute | See `skills/swift-concurrency.md` | | Actor definition, reentrancy, global actors | See `skills/swift-concurrency-ref.md` | | Task/TaskGroup/cancellation API | See `skills/swift-concurrency-ref.md` | | AsyncStream, continuations | See `skills/swift-concurrency-ref.md` | | DispatchQueue → actor migration | See `skills/swift-concurrency-ref.md` | | Mutex (iOS 18+), OSAllocatedUnfairLock | See `skills/synchronization.md` | | Atomic types, lock vs actor decision | See `skills/synchronization.md` | | MainActor.assumeIsolated | See `skills/assume-isolated.md` | | @preconcurrency protocol conformances | See `skills/assume-isolated.md` | | Legacy delegate callbacks | See `skills/assume-isolated.md` | | Warning-free build crashes with `_dispatch_assert_queue_fail` | See `skills/isolation-inheritance-diag.md` | | Crash signature `_swift_task_checkIsolatedSwift` | See `skills/isolation-inheritance-diag.md` | | Core Data `context.perform` runtime crash inside @MainActor class | See `skills/isolation-inheritance-diag.md` | | Combine `.map`/`.sink` crash from receive(on:) placement | See `skills/isolation-inheritance-diag.md` | | Delegate method crash from isolation inheritance (CLLocationManager, NSDocument, AVAudioPlayerDelegate, WKNavigationDelegate, PHPhotoLibraryChangeObserver) | See `skills/isolation-inheritance-diag.md` | | PhotoKit `performChanges` block traps on PhotoKit's queue | See `skills/isolation-inheritance-diag.md` | | Actor reentrancy / stale state across await | See `skills/isolation-inheritance-diag.md` | | Swift Concurrency Instruments template | See `skills/concurrency-profiling.md` | | Actor contention diagnosis | See `skills/concurrency-profiling.md` | | Thread pool exhaustion | See `skills/concurrency-profiling.md` |
## Decision Tree
```dot digraph concurrency { start [label="Concurrency task" shape=ellipse]; what [label="What do you need?" shape=diamond];
start -> what; what -> "skills/swift-concurrency.md" [label="async/await, actors,\nSendable, data races,\nSwift 6 migration"]; what -> "skills/swift-concurrency-ref.md" [label="API syntax lookup\n(TaskGroup, AsyncStream,\ncontinuations, migration)"]; what -> "skills/synchronization.md" [label="Mutex, locks,\natomic types"]; what -> "skills/assume-isolated.md" [label="assumeIsolated,\n@preconcurrency"]; what -> "skills/isolation-inheritance-diag.md" [label="warning-free build crashes\n_dispatch_assert_queue_fail\n_swift_task_checkIsolatedSwift"]; what -> "skills/concurrency-profiling.md" [label="profile async perf,\nactor contention"]; } ```
1. Data races / actor isolation / @MainActor / Sendable / Swift 6 migration? → `skills/swift-concurrency.md` 1a. Need specific API syntax (actor definition, TaskGroup, AsyncStream, continuations)? → `skills/swift-concurrency-ref.md` 1b. NotificationCenter observer, `userInfo` casting, or Sendable errors unpacking a notification? → `skills/swift-concurrency-ref.md` (Typed Notifications — `MainActorMessage`/`AsyncMessage`, iOS 26+) 2. Writing async/await code? → `skills/swift-concurrency.md` 3. assumeIsolated / @preconcurrency? → `skills/assume-isolated.md` 3a. Warning-free Swift 6 build that crashes in production with `_dispatch_assert_queue_fail` or `_swift_task_checkIsolatedSwift`? → `skills/isolation-inheritance-diag.md` 4. Mutex / lock / synchronization? → `skills/synchronization.md` 5. Profile async performance / actor contention? → `skills/concurrency-profiling.md` 6. Value type / ARC / generic optimization? → See axiom-performance (skills/swift-performance.md) 7. borrowing / consuming / ~Copyable? → See axiom-swift (skills/ownership-conventions.md) 8. Combine / @Published / AnyCancellable / reactive streams? → See axiom-uikit (skills/combine-patterns.md) 9. Want automated concurrency scan? → concurrency-auditor (Agent)
#### Concurrency in practice - HealthKit queries with Swift Concurrency (canonical bridging example) → See axiom-health (skills/queries.md)
## Conflict Resolution
**concurrency vs axiom-performance**: When app freezes or feels slow: 1. **Try concurrency FIRST** — Main thread blocking is the #1 cause of UI freezes. Check for synchronous work on @MainActor before profiling. 2. **Only use axiom-performance** if concurrency fixes don't help — Profile after ruling out obvious blocking. 3. **To pin a specific freeze to app code**, see the Hang Window Workflow in axiom-performance (skills/hang-diagnostics.md) — re-scope `xcprof analyze` to the hang window with `--start-ms/--end-ms --user-binary` to surface the app-owned frame on the main thread.
**concurrency vs axiom-build**: When seeing Swift 6 concurrency errors: - **Use concurrency, NOT axiom-build** — Concurrency errors are CODE issues, not environment issues.
**concurrency vs axiom-data**: When concurrency errors involve Core Data or SwiftData: - Core Data threading (NSManagedObjectContext thread confinement) → **use axiom-data first** - SwiftData + @MainActor ModelContext → **use concurrency** - General "background saves losing data" → **use axiom-data first** - GRDB Sendable patterns (struct records, `databaseSelection` as computed property, Swift 6 conformance) → See axiom-data (skills/grdb-performance.md) §8
## Critical Patterns
**Swift Concurrency** (`skills/swift-concurrency.md`): - Progressive journey: single-threaded → async → concurrent → actors - @concurrent attribute for forced background execution - Isolated conformances, main actor mode - 12 copy-paste patterns including delegate value capture, weak self in Tasks - Comprehensive decision tree for 7 common error messages
**API Reference** (`skills/swift-concurrency-ref.md`): - Actor definition, reentrancy, global actors, nonisolated - Sendable patterns, @unchecked Sendable, sending parameter - Task/TaskGroup/cancellation, async let, withDiscardingTaskGroup - AsyncStream, continuations, buffering policies - Isolation patterns (#isolation, @preconcurrency, nonisolated(unsafe)) - DispatchQueue/DispatchGroup/completion handler migration
**Synchronization** (`skills/synchronization.md`): - Mutex (iOS 18+), OSAllocatedUnfairLock (iOS 16+), Atomic types - Lock vs actor decision tree - Danger patterns: locks across await, semaphores in async context
**Profiling** (`skills/concurrency-profiling.md`): - Swift Concurrency Instruments template - Diagnosing main thread blocking, actor contention, thread pool exhaustion - Safe vs unsafe primitives for cooperative pool
**Runtime Isolation Crashes** (`skills/isolation-inheritance-diag.md`): - `_dispatch_assert_queue_fail` and `_swift_task_checkIsolatedSwift` signatures - Closure isolation inheritance (Core Data `perform`, Combine `.map`, NotificationCenter `.sink`) - Delegate method isolation inheritance (CLLocationManager, NSDocument, AVAudioPlayerDelegate, WKNavigationDelegate) - `MainActor.assumeIsolated` misuse - Actor reentrancy state staleness
## Automated Scanning
**Concurrency audit** → Launch `concurrency-auditor` agent or `/axiom:audit concurrency` (5-phase semantic audit: maps isolation architecture, detects 8 anti-patterns, reasons about missing concurrency patterns, correlates compound risks, scores Swift 6.4 readiness)
## Anti-Rationalization
| Thought | Reality | |---------|---------| | "Just add @MainActor and it'll work" | @MainActor has isolation inheritance rules. `skills/swift-concurrency.md` covers all patterns. | | "I'll use nonisolated(unsafe) to silence the warning" | Silencing warnings hides data races. `skills/swift-concurrency.md` shows the safe pattern. | | "It's just one async call" | Even single async calls have cancellation and isolation implications. | | "I know how actors work" | Actor reentrancy and isolation rules changed in Swift 6.2. | | "I'll fix the Sendable warnings later" | Sendable violations cause runtime crashes. Fix them now. | | "My Swift 6 build has zero warnings, so isolation is correct" | Static checking can't see SDK callbacks. Runtime checks crash anyway. `skills/isolation-inheritance-diag.md`. | | "I'll wrap the crash in `MainActor.assumeIsolated`" | `assumeIsolated` is a runtime trap, not a silencer. Wrong assumption = crash. | | "Combine is dead, just use async/await" | Combine has no deprecation notice. Rewriting working pipelines wastes time. See See axiom-uikit (skills/combine-patterns.md). | | "I'll use @unchecked Sendable to silence this" | You're hiding a data race from the compiler. It will crash in production. | | "This async function runs on a background thread" | `async` suspends without blocking but resumes on the *same actor*. Use `@concurrent` to force background. |
## Example Invocations
User: "I'm getting 'data race' errors in Swift 6" → Read: `skills/swift-concurrency.md`
User: "How do I use @MainActor correctly?" → Read: `skills/swift-concurrency.md`
User: "How do I create a TaskGroup?" → Read: `skills/swift-concurrency-ref.md`
User: "What's the AsyncStream API?" → Read: `skills/swift-concurrency-ref.md`
User: "How do I use assumeIsolated?" → Read: `skills/assume-isolated.md`
User: "Should I use Mutex or actor?" → Read: `skills/synchronization.md`
User: "My async code is slow, how do I profile it?" → Read: `skills/concurrency-profiling.md`
User: "My warning-free Swift 6 build crashes in production with _dispatch_assert_queue_fail" → Read: `skills/isolation-inheritance-diag.md`
User: "Core Data `context.perform` crashes inside an @MainActor view model" → Read: `skills/isolation-inheritance-diag.md`
User: "CLLocationManager delegate method is crashing with _swift_task_checkIsolatedSwift" → Read: `skills/isolation-inheritance-diag.md`
User: "My app is slow due to unnecessary copying" → See axiom-performance (skills/swift-performance.md)
User: "Check my code for Swift 6 concurrency issues" → Invoke: `concurrency-auditor` agent
Source provenance
Decision snapshot
1,146 GitHub stars
Audit
Install and adoption review
Agent-proven evidence
Outcome reports after resolve, review, install, and one narrow run.
No agent outcome data yet. The first agent run can report success, setup needs, risk blocks, failure, or not-relevant through /api/agent/outcome.
Install
Free and open source. Review the report before installing into production agents.
Growth loop
Scenario-led draft for axiom-concurrency, ready for a manual X post.
axiom-concurrency: Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swi... 1.1K stars https://www.openagentskill.com/skills/charleswiltgen-axiom-concurrency?ref=x
Listing + install path for axiom-concurrency: https://www.openagentskill.com/skills/charleswiltgen-axiom-concurrency?ref=x Install: npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
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Attribution links to the public repository or creator profile. Creators can claim the listing to update ownership signals.
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Install targets
Codex install prompt
Install the "axiom-concurrency" agent skill from https://github.com/CharlesWiltgen/Axiom/tree/main/.claude-plugin/plugins/axiom/skills/axiom-concurrency. Read its SKILL.md or equivalent instructions first, install only the files needed for this workspace, and summarize any required setup before using it. Skill purpose: Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swift 6 concurrency, @MainActor, Sendable, data races, async/await patterns. After the install attempt, report the result to https://www.openagentskill.com/api/agent/outcome with POST JSON {"event_id":"install_<unique-id>","skill_slug":"charleswiltgen-axiom-concurrency","task":"Install axiom-concurrency","agent":"codex","outcome":"success","install_used":true}. Replace event_id with a unique value and outcome with success or failed. Report success only after the skill is installed and a minimal verification passes.Supply asset profile
Code review, repo analysis, testing, CI, GitHub, DevOps, and developer workflow skills.
Scenario
GitHub automation
I need my agent to triage GitHub issues, review pull requests, and summarize repository changes.
Agent fit
Claude Code + CLI + Codex
Codex, Claude Code, Cursor, CLI, or custom agents.
Install
Ready
npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Maintenance
fresh
9d since push
Risk
Needs review
Dependency or permission surface needs review
GitHub quality
1.1K
78/100 Quality · 79/100 Trust
Coverage tags
Review notes
Dependency or permission surface needs review · Permission surface may require sandboxing
Agent adoption scorecard
These scores combine public repository metadata, OpenAgentSkill review signals, maintenance freshness, and install readiness. They are a shortlist signal, not a replacement for human review.
Quality
StrongSolid option that is likely worth shortlisting for production workflows.
Trust
Sandbox onlyUseful candidate with missing or mixed trust signals. Keep it in an isolated workspace until the outcome loop proves task fit.
Audit
Needs reviewA machine-readable review of install readiness, security metadata, maintenance, and adoption risk.
OpenAgentSkill Trust Score v5
Run only in a sandbox and compare close alternatives before using it for real work.
Stars
1.1K GitHub stars
Repo activity
1.1K stars, 83 forks
Maintenance
9d since push
License
MIT
Install
npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Install safety
Agent-readable metadata
Use this block or the embedded JSON to decide whether an agent should install this skill, choose an alternative, or ask for human review first.
Suited tasks
Suited agents
Install decision
Trust and risk
Outcome loop
Install command
npx skills add CharlesWiltgen/Axiom --skill axiom-concurrencyDo not use when
Agent safety v2
Sparse or mixed signals. Useful for discovery, but not for autonomous installation.
Test manually in an isolated workspace and compare against safer alternatives.
high
Skill metadata references terminal, CLI, shell, subprocess, or command execution workflows.
medium
Skill likely fetches remote pages, APIs, repositories, or external services.
medium
Skill may read or write project files, documents, generated artifacts, or local workspace state.
medium
Skill may inspect schemas, query databases, or work with persistent stores.
Agent resolve plan
The Resolve API returns the selected skill, alternatives, safety policy, audit notes, install target, and copy-paste prompt an agent can follow without scraping this page.
Open JSON
/api/agent/resolve?task=Use%20axiom-concurrency%20for%20an%20agent%20workflow&agent=codex&max_risk=medium
Resolve text
/api/agent/resolve?task=Use%20axiom-concurrency%20for%20an%20agent%20workflow&agent=codex&max_risk=medium&format=text
Install handoff
/api/skills/charleswiltgen-axiom-concurrency/install
Agent should check
Copy prompt
Task: Use axiom-concurrency in this workspace.
Resolve first: https://www.openagentskill.com/api/agent/resolve?task=Use%20axiom-concurrency%20for%20an%20agent%20workflow&agent=codex&max_risk=medium
Review install handoff: https://www.openagentskill.com/api/skills/charleswiltgen-axiom-concurrency/install
Install command: npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Before running it, summarize audit warnings, required permissions, and the fallback skill if install is risky.Agent handoff
Use the public install endpoint to fetch the command, safety checklist, target prompts, and canonical links for this skill.
Install handoff
/api/skills/charleswiltgen-axiom-concurrency/install
LLM text format
/api/skills/charleswiltgen-axiom-concurrency/install?format=text
Find alternatives
/api/skills/search?q=axiom-concurrency&limit=3
Agent prompt
Use axiom-concurrency for this task. Review https://www.openagentskill.com/api/skills/charleswiltgen-axiom-concurrency/install, then install with: npx skills add CharlesWiltgen/Axiom --skill axiom-concurrencyRegistry metadata
This page exposes the same decision, trust, audit, use-case, and install signals through the Registry API, so agents can rank this skill without scraping the UI.
Manifest
/api/registry/manifest/charleswiltgen-axiom-concurrency
LLM text
/api/registry/manifest/charleswiltgen-axiom-concurrency?format=text
Install alias
/api/registry/install/charleswiltgen-axiom-concurrency
Recommend
/api/registry/recommend?task=Use%20axiom-concurrency%20in%20an%20agent%20workflow&limit=3
Agent fit
RAG and knowledge
Platforms
Claude Code
Audit report
A machine-readable review of install readiness, security metadata, maintenance, and adoption risk.
Agent decision cockpit
Use this as a leading candidate, then validate the README and install path in your own agent stack.
Role in stack
Primary pick
Primary fit
RAG and knowledge
Trust label
Production-ready
Install path
Command ready
Use when
Evidence
review first
Implementation path
Trust profile
Useful candidate with missing or mixed trust signals. Keep it in an isolated workspace until the outcome loop proves task fit.
GitHub adoption
PASS1.1K GitHub stars
Stars/forks activity
INFO1.1K stars, 83 forks; issue activity unavailable in current metadata
Recent maintenance
PASS9d since push
License clarity
PASSMIT
Good signals
Review before install
Recommended action
Run only in a sandbox and compare close alternatives before using it for real work.
Quality profile
Solid option that is likely worth shortlisting for production workflows.
Workflow fit
Search private knowledge
I need my agent to build a RAG workflow over documents and retrieve reliable context.
Operate web apps
I need my agent to control a browser, fill forms, and verify web app workflows.
Automate repeated work
I need my agent to automate a repeated workflow across tools and files.
Workflow fit
Operate and verify web apps
A workflow for agents that navigate products, fill forms, take screenshots, and verify real user flows across web applications.
Turn skills into distribution
A workflow for turning newly indexed skills into SEO briefs, social drafts, comparison pages, and reusable publishing workflows.
Ingest, retrieve, and cite
A workflow for document-heavy agents that ingest files, create searchable knowledge, retrieve relevant context, and answer with grounded sources.
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--- name: axiom-concurrency description: Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swift 6 concurrency, @MainActor, Sendable, data races, async/await patterns. license: MIT ---
# Concurrency
**You MUST use this skill for ANY concurrency, async/await, threading, or Swift 6 concurrency 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/concurrency-auditor.md`. > > Agents that need Bash — builds, tests, simulators, crash symbolication — stay Claude Code-only; there is no inline equivalent for those. <!-- AXIOM_AUDITOR_INLINE_END -->
## Quick Reference
| Symptom / Task | Reference | |----------------|-----------| | async/await patterns, @MainActor, actors | See `skills/swift-concurrency.md` | | Data race errors, Sendable conformance | See `skills/swift-concurrency.md` | | Swift 6 migration, @concurrent attribute | See `skills/swift-concurrency.md` | | Actor definition, reentrancy, global actors | See `skills/swift-concurrency-ref.md` | | Task/TaskGroup/cancellation API | See `skills/swift-concurrency-ref.md` | | AsyncStream, continuations | See `skills/swift-concurrency-ref.md` | | DispatchQueue → actor migration | See `skills/swift-concurrency-ref.md` | | Mutex (iOS 18+), OSAllocatedUnfairLock | See `skills/synchronization.md` | | Atomic types, lock vs actor decision | See `skills/synchronization.md` | | MainActor.assumeIsolated | See `skills/assume-isolated.md` | | @preconcurrency protocol conformances | See `skills/assume-isolated.md` | | Legacy delegate callbacks | See `skills/assume-isolated.md` | | Warning-free build crashes with `_dispatch_assert_queue_fail` | See `skills/isolation-inheritance-diag.md` | | Crash signature `_swift_task_checkIsolatedSwift` | See `skills/isolation-inheritance-diag.md` | | Core Data `context.perform` runtime crash inside @MainActor class | See `skills/isolation-inheritance-diag.md` | | Combine `.map`/`.sink` crash from receive(on:) placement | See `skills/isolation-inheritance-diag.md` | | Delegate method crash from isolation inheritance (CLLocationManager, NSDocument, AVAudioPlayerDelegate, WKNavigationDelegate, PHPhotoLibraryChangeObserver) | See `skills/isolation-inheritance-diag.md` | | PhotoKit `performChanges` block traps on PhotoKit's queue | See `skills/isolation-inheritance-diag.md` | | Actor reentrancy / stale state across await | See `skills/isolation-inheritance-diag.md` | | Swift Concurrency Instruments template | See `skills/concurrency-profiling.md` | | Actor contention diagnosis | See `skills/concurrency-profiling.md` | | Thread pool exhaustion | See `skills/concurrency-profiling.md` |
## Decision Tree
```dot digraph concurrency { start [label="Concurrency task" shape=ellipse]; what [label="What do you need?" shape=diamond];
start -> what; what -> "skills/swift-concurrency.md" [label="async/await, actors,\nSendable, data races,\nSwift 6 migration"]; what -> "skills/swift-concurrency-ref.md" [label="API syntax lookup\n(TaskGroup, AsyncStream,\ncontinuations, migration)"]; what -> "skills/synchronization.md" [label="Mutex, locks,\natomic types"]; what -> "skills/assume-isolated.md" [label="assumeIsolated,\n@preconcurrency"]; what -> "skills/isolation-inheritance-diag.md" [label="warning-free build crashes\n_dispatch_assert_queue_fail\n_swift_task_checkIsolatedSwift"]; what -> "skills/concurrency-profiling.md" [label="profile async perf,\nactor contention"]; } ```
1. Data races / actor isolation / @MainActor / Sendable / Swift 6 migration? → `skills/swift-concurrency.md` 1a. Need specific API syntax (actor definition, TaskGroup, AsyncStream, continuations)? → `skills/swift-concurrency-ref.md` 1b. NotificationCenter observer, `userInfo` casting, or Sendable errors unpacking a notification? → `skills/swift-concurrency-ref.md` (Typed Notifications — `MainActorMessage`/`AsyncMessage`, iOS 26+) 2. Writing async/await code? → `skills/swift-concurrency.md` 3. assumeIsolated / @preconcurrency? → `skills/assume-isolated.md` 3a. Warning-free Swift 6 build that crashes in production with `_dispatch_assert_queue_fail` or `_swift_task_checkIsolatedSwift`? → `skills/isolation-inheritance-diag.md` 4. Mutex / lock / synchronization? → `skills/synchronization.md` 5. Profile async performance / actor contention? → `skills/concurrency-profiling.md` 6. Value type / ARC / generic optimization? → See axiom-performance (skills/swift-performance.md) 7. borrowing / consuming / ~Copyable? → See axiom-swift (skills/ownership-conventions.md) 8. Combine / @Published / AnyCancellable / reactive streams? → See axiom-uikit (skills/combine-patterns.md) 9. Want automated concurrency scan? → concurrency-auditor (Agent)
#### Concurrency in practice - HealthKit queries with Swift Concurrency (canonical bridging example) → See axiom-health (skills/queries.md)
## Conflict Resolution
**concurrency vs axiom-performance**: When app freezes or feels slow: 1. **Try concurrency FIRST** — Main thread blocking is the #1 cause of UI freezes. Check for synchronous work on @MainActor before profiling. 2. **Only use axiom-performance** if concurrency fixes don't help — Profile after ruling out obvious blocking. 3. **To pin a specific freeze to app code**, see the Hang Window Workflow in axiom-performance (skills/hang-diagnostics.md) — re-scope `xcprof analyze` to the hang window with `--start-ms/--end-ms --user-binary` to surface the app-owned frame on the main thread.
**concurrency vs axiom-build**: When seeing Swift 6 concurrency errors: - **Use concurrency, NOT axiom-build** — Concurrency errors are CODE issues, not environment issues.
**concurrency vs axiom-data**: When concurrency errors involve Core Data or SwiftData: - Core Data threading (NSManagedObjectContext thread confinement) → **use axiom-data first** - SwiftData + @MainActor ModelContext → **use concurrency** - General "background saves losing data" → **use axiom-data first** - GRDB Sendable patterns (struct records, `databaseSelection` as computed property, Swift 6 conformance) → See axiom-data (skills/grdb-performance.md) §8
## Critical Patterns
**Swift Concurrency** (`skills/swift-concurrency.md`): - Progressive journey: single-threaded → async → concurrent → actors - @concurrent attribute for forced background execution - Isolated conformances, main actor mode - 12 copy-paste patterns including delegate value capture, weak self in Tasks - Comprehensive decision tree for 7 common error messages
**API Reference** (`skills/swift-concurrency-ref.md`): - Actor definition, reentrancy, global actors, nonisolated - Sendable patterns, @unchecked Sendable, sending parameter - Task/TaskGroup/cancellation, async let, withDiscardingTaskGroup - AsyncStream, continuations, buffering policies - Isolation patterns (#isolation, @preconcurrency, nonisolated(unsafe)) - DispatchQueue/DispatchGroup/completion handler migration
**Synchronization** (`skills/synchronization.md`): - Mutex (iOS 18+), OSAllocatedUnfairLock (iOS 16+), Atomic types - Lock vs actor decision tree - Danger patterns: locks across await, semaphores in async context
**Profiling** (`skills/concurrency-profiling.md`): - Swift Concurrency Instruments template - Diagnosing main thread blocking, actor contention, thread pool exhaustion - Safe vs unsafe primitives for cooperative pool
**Runtime Isolation Crashes** (`skills/isolation-inheritance-diag.md`): - `_dispatch_assert_queue_fail` and `_swift_task_checkIsolatedSwift` signatures - Closure isolation inheritance (Core Data `perform`, Combine `.map`, NotificationCenter `.sink`) - Delegate method isolation inheritance (CLLocationManager, NSDocument, AVAudioPlayerDelegate, WKNavigationDelegate) - `MainActor.assumeIsolated` misuse - Actor reentrancy state staleness
## Automated Scanning
**Concurrency audit** → Launch `concurrency-auditor` agent or `/axiom:audit concurrency` (5-phase semantic audit: maps isolation architecture, detects 8 anti-patterns, reasons about missing concurrency patterns, correlates compound risks, scores Swift 6.4 readiness)
## Anti-Rationalization
| Thought | Reality | |---------|---------| | "Just add @MainActor and it'll work" | @MainActor has isolation inheritance rules. `skills/swift-concurrency.md` covers all patterns. | | "I'll use nonisolated(unsafe) to silence the warning" | Silencing warnings hides data races. `skills/swift-concurrency.md` shows the safe pattern. | | "It's just one async call" | Even single async calls have cancellation and isolation implications. | | "I know how actors work" | Actor reentrancy and isolation rules changed in Swift 6.2. | | "I'll fix the Sendable warnings later" | Sendable violations cause runtime crashes. Fix them now. | | "My Swift 6 build has zero warnings, so isolation is correct" | Static checking can't see SDK callbacks. Runtime checks crash anyway. `skills/isolation-inheritance-diag.md`. | | "I'll wrap the crash in `MainActor.assumeIsolated`" | `assumeIsolated` is a runtime trap, not a silencer. Wrong assumption = crash. | | "Combine is dead, just use async/await" | Combine has no deprecation notice. Rewriting working pipelines wastes time. See See axiom-uikit (skills/combine-patterns.md). | | "I'll use @unchecked Sendable to silence this" | You're hiding a data race from the compiler. It will crash in production. | | "This async function runs on a background thread" | `async` suspends without blocking but resumes on the *same actor*. Use `@concurrent` to force background. |
## Example Invocations
User: "I'm getting 'data race' errors in Swift 6" → Read: `skills/swift-concurrency.md`
User: "How do I use @MainActor correctly?" → Read: `skills/swift-concurrency.md`
User: "How do I create a TaskGroup?" → Read: `skills/swift-concurrency-ref.md`
User: "What's the AsyncStream API?" → Read: `skills/swift-concurrency-ref.md`
User: "How do I use assumeIsolated?" → Read: `skills/assume-isolated.md`
User: "Should I use Mutex or actor?" → Read: `skills/synchronization.md`
User: "My async code is slow, how do I profile it?" → Read: `skills/concurrency-profiling.md`
User: "My warning-free Swift 6 build crashes in production with _dispatch_assert_queue_fail" → Read: `skills/isolation-inheritance-diag.md`
User: "Core Data `context.perform` crashes inside an @MainActor view model" → Read: `skills/isolation-inheritance-diag.md`
User: "CLLocationManager delegate method is crashing with _swift_task_checkIsolatedSwift" → Read: `skills/isolation-inheritance-diag.md`
User: "My app is slow due to unnecessary copying" → See axiom-performance (skills/swift-performance.md)
User: "Check my code for Swift 6 concurrency issues" → Invoke: `concurrency-auditor` agent
Source provenance
Decision snapshot
1,146 GitHub stars
Audit
Install and adoption review
Agent-proven evidence
Outcome reports after resolve, review, install, and one narrow run.
No agent outcome data yet. The first agent run can report success, setup needs, risk blocks, failure, or not-relevant through /api/agent/outcome.
Install
Free and open source. Review the report before installing into production agents.
Growth loop
Scenario-led draft for axiom-concurrency, ready for a manual X post.
axiom-concurrency: Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swi... 1.1K stars https://www.openagentskill.com/skills/charleswiltgen-axiom-concurrency?ref=x
Listing + install path for axiom-concurrency: https://www.openagentskill.com/skills/charleswiltgen-axiom-concurrency?ref=x Install: npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Listing source
This listing was indexed from public sources and is not marked official until a maintainer claim is approved.
Attribution links to the public repository or creator profile. Creators can claim the listing to update ownership signals.
Claim this skillOwner claim
This Registry indexed listing is attributed to CharlesWiltgen but is not marked official yet. Claim it to add a verified owner signal and make future launch, install, and audit updates easier to trust.
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@charleswiltgen
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Install targets
Codex install prompt
Install the "axiom-concurrency" agent skill from https://github.com/CharlesWiltgen/Axiom/tree/main/.claude-plugin/plugins/axiom/skills/axiom-concurrency. Read its SKILL.md or equivalent instructions first, install only the files needed for this workspace, and summarize any required setup before using it. Skill purpose: Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swift 6 concurrency, @MainActor, Sendable, data races, async/await patterns. After the install attempt, report the result to https://www.openagentskill.com/api/agent/outcome with POST JSON {"event_id":"install_<unique-id>","skill_slug":"charleswiltgen-axiom-concurrency","task":"Install axiom-concurrency","agent":"codex","outcome":"success","install_used":true}. Replace event_id with a unique value and outcome with success or failed. Report success only after the skill is installed and a minimal verification passes.Supply asset profile
Code review, repo analysis, testing, CI, GitHub, DevOps, and developer workflow skills.
Scenario
GitHub automation
I need my agent to triage GitHub issues, review pull requests, and summarize repository changes.
Agent fit
Claude Code + CLI + Codex
Codex, Claude Code, Cursor, CLI, or custom agents.
Install
Ready
npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Maintenance
fresh
9d since push
Risk
Needs review
Dependency or permission surface needs review
GitHub quality
1.1K
78/100 Quality · 79/100 Trust
Coverage tags
Review notes
Dependency or permission surface needs review · Permission surface may require sandboxing
Agent adoption scorecard
These scores combine public repository metadata, OpenAgentSkill review signals, maintenance freshness, and install readiness. They are a shortlist signal, not a replacement for human review.
Quality
StrongSolid option that is likely worth shortlisting for production workflows.
Trust
Sandbox onlyUseful candidate with missing or mixed trust signals. Keep it in an isolated workspace until the outcome loop proves task fit.
Audit
Needs reviewA machine-readable review of install readiness, security metadata, maintenance, and adoption risk.
OpenAgentSkill Trust Score v5
Run only in a sandbox and compare close alternatives before using it for real work.
Stars
1.1K GitHub stars
Repo activity
1.1K stars, 83 forks
Maintenance
9d since push
License
MIT
Install
npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Install safety
Agent-readable metadata
Use this block or the embedded JSON to decide whether an agent should install this skill, choose an alternative, or ask for human review first.
Suited tasks
Suited agents
Install decision
Trust and risk
Outcome loop
Install command
npx skills add CharlesWiltgen/Axiom --skill axiom-concurrencyDo not use when
Agent safety v2
Sparse or mixed signals. Useful for discovery, but not for autonomous installation.
Test manually in an isolated workspace and compare against safer alternatives.
high
Skill metadata references terminal, CLI, shell, subprocess, or command execution workflows.
medium
Skill likely fetches remote pages, APIs, repositories, or external services.
medium
Skill may read or write project files, documents, generated artifacts, or local workspace state.
medium
Skill may inspect schemas, query databases, or work with persistent stores.
Agent resolve plan
The Resolve API returns the selected skill, alternatives, safety policy, audit notes, install target, and copy-paste prompt an agent can follow without scraping this page.
Open JSON
/api/agent/resolve?task=Use%20axiom-concurrency%20for%20an%20agent%20workflow&agent=codex&max_risk=medium
Resolve text
/api/agent/resolve?task=Use%20axiom-concurrency%20for%20an%20agent%20workflow&agent=codex&max_risk=medium&format=text
Install handoff
/api/skills/charleswiltgen-axiom-concurrency/install
Agent should check
Copy prompt
Task: Use axiom-concurrency in this workspace.
Resolve first: https://www.openagentskill.com/api/agent/resolve?task=Use%20axiom-concurrency%20for%20an%20agent%20workflow&agent=codex&max_risk=medium
Review install handoff: https://www.openagentskill.com/api/skills/charleswiltgen-axiom-concurrency/install
Install command: npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Before running it, summarize audit warnings, required permissions, and the fallback skill if install is risky.Agent handoff
Use the public install endpoint to fetch the command, safety checklist, target prompts, and canonical links for this skill.
Install handoff
/api/skills/charleswiltgen-axiom-concurrency/install
LLM text format
/api/skills/charleswiltgen-axiom-concurrency/install?format=text
Find alternatives
/api/skills/search?q=axiom-concurrency&limit=3
Agent prompt
Use axiom-concurrency for this task. Review https://www.openagentskill.com/api/skills/charleswiltgen-axiom-concurrency/install, then install with: npx skills add CharlesWiltgen/Axiom --skill axiom-concurrencyRegistry metadata
This page exposes the same decision, trust, audit, use-case, and install signals through the Registry API, so agents can rank this skill without scraping the UI.
Manifest
/api/registry/manifest/charleswiltgen-axiom-concurrency
LLM text
/api/registry/manifest/charleswiltgen-axiom-concurrency?format=text
Install alias
/api/registry/install/charleswiltgen-axiom-concurrency
Recommend
/api/registry/recommend?task=Use%20axiom-concurrency%20in%20an%20agent%20workflow&limit=3
Agent fit
RAG and knowledge
Platforms
Claude Code
Audit report
A machine-readable review of install readiness, security metadata, maintenance, and adoption risk.
Agent decision cockpit
Use this as a leading candidate, then validate the README and install path in your own agent stack.
Role in stack
Primary pick
Primary fit
RAG and knowledge
Trust label
Production-ready
Install path
Command ready
Use when
Evidence
review first
Implementation path
Trust profile
Useful candidate with missing or mixed trust signals. Keep it in an isolated workspace until the outcome loop proves task fit.
GitHub adoption
PASS1.1K GitHub stars
Stars/forks activity
INFO1.1K stars, 83 forks; issue activity unavailable in current metadata
Recent maintenance
PASS9d since push
License clarity
PASSMIT
Good signals
Review before install
Recommended action
Run only in a sandbox and compare close alternatives before using it for real work.
Quality profile
Solid option that is likely worth shortlisting for production workflows.
Workflow fit
Search private knowledge
I need my agent to build a RAG workflow over documents and retrieve reliable context.
Operate web apps
I need my agent to control a browser, fill forms, and verify web app workflows.
Automate repeated work
I need my agent to automate a repeated workflow across tools and files.
Workflow fit
Operate and verify web apps
A workflow for agents that navigate products, fill forms, take screenshots, and verify real user flows across web applications.
Turn skills into distribution
A workflow for turning newly indexed skills into SEO briefs, social drafts, comparison pages, and reusable publishing workflows.
Ingest, retrieve, and cite
A workflow for document-heavy agents that ingest files, create searchable knowledge, retrieve relevant context, and answer with grounded sources.
Alternative shortlist
Similar skills that may fit this task.
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Turn any AI agent into an AI Scientist. The #1 Agent Skills library for science, used by 160,000+ scientists worldwide. 140 ready-to-use skills plus 100+ scientific databases covering biology, chemistry, medicine, and drug discovery. Compatible with Cursor, Claude Code, Codex, Pi, Antigravity, and the open Agent Skills standard.
Apache Superset is a Data Visualization and Data Exploration Platform
--- name: axiom-concurrency description: Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swift 6 concurrency, @MainActor, Sendable, data races, async/await patterns. license: MIT ---
# Concurrency
**You MUST use this skill for ANY concurrency, async/await, threading, or Swift 6 concurrency 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/concurrency-auditor.md`. > > Agents that need Bash — builds, tests, simulators, crash symbolication — stay Claude Code-only; there is no inline equivalent for those. <!-- AXIOM_AUDITOR_INLINE_END -->
## Quick Reference
| Symptom / Task | Reference | |----------------|-----------| | async/await patterns, @MainActor, actors | See `skills/swift-concurrency.md` | | Data race errors, Sendable conformance | See `skills/swift-concurrency.md` | | Swift 6 migration, @concurrent attribute | See `skills/swift-concurrency.md` | | Actor definition, reentrancy, global actors | See `skills/swift-concurrency-ref.md` | | Task/TaskGroup/cancellation API | See `skills/swift-concurrency-ref.md` | | AsyncStream, continuations | See `skills/swift-concurrency-ref.md` | | DispatchQueue → actor migration | See `skills/swift-concurrency-ref.md` | | Mutex (iOS 18+), OSAllocatedUnfairLock | See `skills/synchronization.md` | | Atomic types, lock vs actor decision | See `skills/synchronization.md` | | MainActor.assumeIsolated | See `skills/assume-isolated.md` | | @preconcurrency protocol conformances | See `skills/assume-isolated.md` | | Legacy delegate callbacks | See `skills/assume-isolated.md` | | Warning-free build crashes with `_dispatch_assert_queue_fail` | See `skills/isolation-inheritance-diag.md` | | Crash signature `_swift_task_checkIsolatedSwift` | See `skills/isolation-inheritance-diag.md` | | Core Data `context.perform` runtime crash inside @MainActor class | See `skills/isolation-inheritance-diag.md` | | Combine `.map`/`.sink` crash from receive(on:) placement | See `skills/isolation-inheritance-diag.md` | | Delegate method crash from isolation inheritance (CLLocationManager, NSDocument, AVAudioPlayerDelegate, WKNavigationDelegate, PHPhotoLibraryChangeObserver) | See `skills/isolation-inheritance-diag.md` | | PhotoKit `performChanges` block traps on PhotoKit's queue | See `skills/isolation-inheritance-diag.md` | | Actor reentrancy / stale state across await | See `skills/isolation-inheritance-diag.md` | | Swift Concurrency Instruments template | See `skills/concurrency-profiling.md` | | Actor contention diagnosis | See `skills/concurrency-profiling.md` | | Thread pool exhaustion | See `skills/concurrency-profiling.md` |
## Decision Tree
```dot digraph concurrency { start [label="Concurrency task" shape=ellipse]; what [label="What do you need?" shape=diamond];
start -> what; what -> "skills/swift-concurrency.md" [label="async/await, actors,\nSendable, data races,\nSwift 6 migration"]; what -> "skills/swift-concurrency-ref.md" [label="API syntax lookup\n(TaskGroup, AsyncStream,\ncontinuations, migration)"]; what -> "skills/synchronization.md" [label="Mutex, locks,\natomic types"]; what -> "skills/assume-isolated.md" [label="assumeIsolated,\n@preconcurrency"]; what -> "skills/isolation-inheritance-diag.md" [label="warning-free build crashes\n_dispatch_assert_queue_fail\n_swift_task_checkIsolatedSwift"]; what -> "skills/concurrency-profiling.md" [label="profile async perf,\nactor contention"]; } ```
1. Data races / actor isolation / @MainActor / Sendable / Swift 6 migration? → `skills/swift-concurrency.md` 1a. Need specific API syntax (actor definition, TaskGroup, AsyncStream, continuations)? → `skills/swift-concurrency-ref.md` 1b. NotificationCenter observer, `userInfo` casting, or Sendable errors unpacking a notification? → `skills/swift-concurrency-ref.md` (Typed Notifications — `MainActorMessage`/`AsyncMessage`, iOS 26+) 2. Writing async/await code? → `skills/swift-concurrency.md` 3. assumeIsolated / @preconcurrency? → `skills/assume-isolated.md` 3a. Warning-free Swift 6 build that crashes in production with `_dispatch_assert_queue_fail` or `_swift_task_checkIsolatedSwift`? → `skills/isolation-inheritance-diag.md` 4. Mutex / lock / synchronization? → `skills/synchronization.md` 5. Profile async performance / actor contention? → `skills/concurrency-profiling.md` 6. Value type / ARC / generic optimization? → See axiom-performance (skills/swift-performance.md) 7. borrowing / consuming / ~Copyable? → See axiom-swift (skills/ownership-conventions.md) 8. Combine / @Published / AnyCancellable / reactive streams? → See axiom-uikit (skills/combine-patterns.md) 9. Want automated concurrency scan? → concurrency-auditor (Agent)
#### Concurrency in practice - HealthKit queries with Swift Concurrency (canonical bridging example) → See axiom-health (skills/queries.md)
## Conflict Resolution
**concurrency vs axiom-performance**: When app freezes or feels slow: 1. **Try concurrency FIRST** — Main thread blocking is the #1 cause of UI freezes. Check for synchronous work on @MainActor before profiling. 2. **Only use axiom-performance** if concurrency fixes don't help — Profile after ruling out obvious blocking. 3. **To pin a specific freeze to app code**, see the Hang Window Workflow in axiom-performance (skills/hang-diagnostics.md) — re-scope `xcprof analyze` to the hang window with `--start-ms/--end-ms --user-binary` to surface the app-owned frame on the main thread.
**concurrency vs axiom-build**: When seeing Swift 6 concurrency errors: - **Use concurrency, NOT axiom-build** — Concurrency errors are CODE issues, not environment issues.
**concurrency vs axiom-data**: When concurrency errors involve Core Data or SwiftData: - Core Data threading (NSManagedObjectContext thread confinement) → **use axiom-data first** - SwiftData + @MainActor ModelContext → **use concurrency** - General "background saves losing data" → **use axiom-data first** - GRDB Sendable patterns (struct records, `databaseSelection` as computed property, Swift 6 conformance) → See axiom-data (skills/grdb-performance.md) §8
## Critical Patterns
**Swift Concurrency** (`skills/swift-concurrency.md`): - Progressive journey: single-threaded → async → concurrent → actors - @concurrent attribute for forced background execution - Isolated conformances, main actor mode - 12 copy-paste patterns including delegate value capture, weak self in Tasks - Comprehensive decision tree for 7 common error messages
**API Reference** (`skills/swift-concurrency-ref.md`): - Actor definition, reentrancy, global actors, nonisolated - Sendable patterns, @unchecked Sendable, sending parameter - Task/TaskGroup/cancellation, async let, withDiscardingTaskGroup - AsyncStream, continuations, buffering policies - Isolation patterns (#isolation, @preconcurrency, nonisolated(unsafe)) - DispatchQueue/DispatchGroup/completion handler migration
**Synchronization** (`skills/synchronization.md`): - Mutex (iOS 18+), OSAllocatedUnfairLock (iOS 16+), Atomic types - Lock vs actor decision tree - Danger patterns: locks across await, semaphores in async context
**Profiling** (`skills/concurrency-profiling.md`): - Swift Concurrency Instruments template - Diagnosing main thread blocking, actor contention, thread pool exhaustion - Safe vs unsafe primitives for cooperative pool
**Runtime Isolation Crashes** (`skills/isolation-inheritance-diag.md`): - `_dispatch_assert_queue_fail` and `_swift_task_checkIsolatedSwift` signatures - Closure isolation inheritance (Core Data `perform`, Combine `.map`, NotificationCenter `.sink`) - Delegate method isolation inheritance (CLLocationManager, NSDocument, AVAudioPlayerDelegate, WKNavigationDelegate) - `MainActor.assumeIsolated` misuse - Actor reentrancy state staleness
## Automated Scanning
**Concurrency audit** → Launch `concurrency-auditor` agent or `/axiom:audit concurrency` (5-phase semantic audit: maps isolation architecture, detects 8 anti-patterns, reasons about missing concurrency patterns, correlates compound risks, scores Swift 6.4 readiness)
## Anti-Rationalization
| Thought | Reality | |---------|---------| | "Just add @MainActor and it'll work" | @MainActor has isolation inheritance rules. `skills/swift-concurrency.md` covers all patterns. | | "I'll use nonisolated(unsafe) to silence the warning" | Silencing warnings hides data races. `skills/swift-concurrency.md` shows the safe pattern. | | "It's just one async call" | Even single async calls have cancellation and isolation implications. | | "I know how actors work" | Actor reentrancy and isolation rules changed in Swift 6.2. | | "I'll fix the Sendable warnings later" | Sendable violations cause runtime crashes. Fix them now. | | "My Swift 6 build has zero warnings, so isolation is correct" | Static checking can't see SDK callbacks. Runtime checks crash anyway. `skills/isolation-inheritance-diag.md`. | | "I'll wrap the crash in `MainActor.assumeIsolated`" | `assumeIsolated` is a runtime trap, not a silencer. Wrong assumption = crash. | | "Combine is dead, just use async/await" | Combine has no deprecation notice. Rewriting working pipelines wastes time. See See axiom-uikit (skills/combine-patterns.md). | | "I'll use @unchecked Sendable to silence this" | You're hiding a data race from the compiler. It will crash in production. | | "This async function runs on a background thread" | `async` suspends without blocking but resumes on the *same actor*. Use `@concurrent` to force background. |
## Example Invocations
User: "I'm getting 'data race' errors in Swift 6" → Read: `skills/swift-concurrency.md`
User: "How do I use @MainActor correctly?" → Read: `skills/swift-concurrency.md`
User: "How do I create a TaskGroup?" → Read: `skills/swift-concurrency-ref.md`
User: "What's the AsyncStream API?" → Read: `skills/swift-concurrency-ref.md`
User: "How do I use assumeIsolated?" → Read: `skills/assume-isolated.md`
User: "Should I use Mutex or actor?" → Read: `skills/synchronization.md`
User: "My async code is slow, how do I profile it?" → Read: `skills/concurrency-profiling.md`
User: "My warning-free Swift 6 build crashes in production with _dispatch_assert_queue_fail" → Read: `skills/isolation-inheritance-diag.md`
User: "Core Data `context.perform` crashes inside an @MainActor view model" → Read: `skills/isolation-inheritance-diag.md`
User: "CLLocationManager delegate method is crashing with _swift_task_checkIsolatedSwift" → Read: `skills/isolation-inheritance-diag.md`
User: "My app is slow due to unnecessary copying" → See axiom-performance (skills/swift-performance.md)
User: "Check my code for Swift 6 concurrency issues" → Invoke: `concurrency-auditor` agent
Source provenance
Decision snapshot
1,146 GitHub stars
Audit
Install and adoption review
Agent-proven evidence
Outcome reports after resolve, review, install, and one narrow run.
No agent outcome data yet. The first agent run can report success, setup needs, risk blocks, failure, or not-relevant through /api/agent/outcome.
Install
Free and open source. Review the report before installing into production agents.
Growth loop
Scenario-led draft for axiom-concurrency, ready for a manual X post.
axiom-concurrency: Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swi... 1.1K stars https://www.openagentskill.com/skills/charleswiltgen-axiom-concurrency?ref=x
Listing + install path for axiom-concurrency: https://www.openagentskill.com/skills/charleswiltgen-axiom-concurrency?ref=x Install: npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
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Install targets
Codex install prompt
Install the "axiom-concurrency" agent skill from https://github.com/CharlesWiltgen/Axiom/tree/main/.claude-plugin/plugins/axiom/skills/axiom-concurrency. Read its SKILL.md or equivalent instructions first, install only the files needed for this workspace, and summarize any required setup before using it. Skill purpose: Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swift 6 concurrency, @MainActor, Sendable, data races, async/await patterns. After the install attempt, report the result to https://www.openagentskill.com/api/agent/outcome with POST JSON {"event_id":"install_<unique-id>","skill_slug":"charleswiltgen-axiom-concurrency","task":"Install axiom-concurrency","agent":"codex","outcome":"success","install_used":true}. Replace event_id with a unique value and outcome with success or failed. Report success only after the skill is installed and a minimal verification passes.Supply asset profile
Code review, repo analysis, testing, CI, GitHub, DevOps, and developer workflow skills.
Scenario
GitHub automation
I need my agent to triage GitHub issues, review pull requests, and summarize repository changes.
Agent fit
Claude Code + CLI + Codex
Codex, Claude Code, Cursor, CLI, or custom agents.
Install
Ready
npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Maintenance
fresh
9d since push
Risk
Needs review
Dependency or permission surface needs review
GitHub quality
1.1K
78/100 Quality · 79/100 Trust
Coverage tags
Review notes
Dependency or permission surface needs review · Permission surface may require sandboxing
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Quality
StrongSolid option that is likely worth shortlisting for production workflows.
Trust
Sandbox onlyUseful candidate with missing or mixed trust signals. Keep it in an isolated workspace until the outcome loop proves task fit.
Audit
Needs reviewA machine-readable review of install readiness, security metadata, maintenance, and adoption risk.
OpenAgentSkill Trust Score v5
Run only in a sandbox and compare close alternatives before using it for real work.
Stars
1.1K GitHub stars
Repo activity
1.1K stars, 83 forks
Maintenance
9d since push
License
MIT
Install
npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Install safety
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npx skills add CharlesWiltgen/Axiom --skill axiom-concurrencyDo not use when
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Test manually in an isolated workspace and compare against safer alternatives.
high
Skill metadata references terminal, CLI, shell, subprocess, or command execution workflows.
medium
Skill likely fetches remote pages, APIs, repositories, or external services.
medium
Skill may read or write project files, documents, generated artifacts, or local workspace state.
medium
Skill may inspect schemas, query databases, or work with persistent stores.
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Open JSON
/api/agent/resolve?task=Use%20axiom-concurrency%20for%20an%20agent%20workflow&agent=codex&max_risk=medium
Resolve text
/api/agent/resolve?task=Use%20axiom-concurrency%20for%20an%20agent%20workflow&agent=codex&max_risk=medium&format=text
Install handoff
/api/skills/charleswiltgen-axiom-concurrency/install
Agent should check
Copy prompt
Task: Use axiom-concurrency in this workspace.
Resolve first: https://www.openagentskill.com/api/agent/resolve?task=Use%20axiom-concurrency%20for%20an%20agent%20workflow&agent=codex&max_risk=medium
Review install handoff: https://www.openagentskill.com/api/skills/charleswiltgen-axiom-concurrency/install
Install command: npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
Before running it, summarize audit warnings, required permissions, and the fallback skill if install is risky.Agent handoff
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/api/skills/charleswiltgen-axiom-concurrency/install
LLM text format
/api/skills/charleswiltgen-axiom-concurrency/install?format=text
Find alternatives
/api/skills/search?q=axiom-concurrency&limit=3
Agent prompt
Use axiom-concurrency for this task. Review https://www.openagentskill.com/api/skills/charleswiltgen-axiom-concurrency/install, then install with: npx skills add CharlesWiltgen/Axiom --skill axiom-concurrencyRegistry metadata
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/api/registry/manifest/charleswiltgen-axiom-concurrency
LLM text
/api/registry/manifest/charleswiltgen-axiom-concurrency?format=text
Install alias
/api/registry/install/charleswiltgen-axiom-concurrency
Recommend
/api/registry/recommend?task=Use%20axiom-concurrency%20in%20an%20agent%20workflow&limit=3
Agent fit
RAG and knowledge
Platforms
Claude Code
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A machine-readable review of install readiness, security metadata, maintenance, and adoption risk.
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Production-ready
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Command ready
Use when
Evidence
review first
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Trust profile
Useful candidate with missing or mixed trust signals. Keep it in an isolated workspace until the outcome loop proves task fit.
GitHub adoption
PASS1.1K GitHub stars
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INFO1.1K stars, 83 forks; issue activity unavailable in current metadata
Recent maintenance
PASS9d since push
License clarity
PASSMIT
Good signals
Review before install
Recommended action
Run only in a sandbox and compare close alternatives before using it for real work.
Quality profile
Solid option that is likely worth shortlisting for production workflows.
Workflow fit
Search private knowledge
I need my agent to build a RAG workflow over documents and retrieve reliable context.
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Similar skills that may fit this task.
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--- name: axiom-concurrency description: Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swift 6 concurrency, @MainActor, Sendable, data races, async/await patterns. license: MIT ---
# Concurrency
**You MUST use this skill for ANY concurrency, async/await, threading, or Swift 6 concurrency 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/concurrency-auditor.md`. > > Agents that need Bash — builds, tests, simulators, crash symbolication — stay Claude Code-only; there is no inline equivalent for those. <!-- AXIOM_AUDITOR_INLINE_END -->
## Quick Reference
| Symptom / Task | Reference | |----------------|-----------| | async/await patterns, @MainActor, actors | See `skills/swift-concurrency.md` | | Data race errors, Sendable conformance | See `skills/swift-concurrency.md` | | Swift 6 migration, @concurrent attribute | See `skills/swift-concurrency.md` | | Actor definition, reentrancy, global actors | See `skills/swift-concurrency-ref.md` | | Task/TaskGroup/cancellation API | See `skills/swift-concurrency-ref.md` | | AsyncStream, continuations | See `skills/swift-concurrency-ref.md` | | DispatchQueue → actor migration | See `skills/swift-concurrency-ref.md` | | Mutex (iOS 18+), OSAllocatedUnfairLock | See `skills/synchronization.md` | | Atomic types, lock vs actor decision | See `skills/synchronization.md` | | MainActor.assumeIsolated | See `skills/assume-isolated.md` | | @preconcurrency protocol conformances | See `skills/assume-isolated.md` | | Legacy delegate callbacks | See `skills/assume-isolated.md` | | Warning-free build crashes with `_dispatch_assert_queue_fail` | See `skills/isolation-inheritance-diag.md` | | Crash signature `_swift_task_checkIsolatedSwift` | See `skills/isolation-inheritance-diag.md` | | Core Data `context.perform` runtime crash inside @MainActor class | See `skills/isolation-inheritance-diag.md` | | Combine `.map`/`.sink` crash from receive(on:) placement | See `skills/isolation-inheritance-diag.md` | | Delegate method crash from isolation inheritance (CLLocationManager, NSDocument, AVAudioPlayerDelegate, WKNavigationDelegate, PHPhotoLibraryChangeObserver) | See `skills/isolation-inheritance-diag.md` | | PhotoKit `performChanges` block traps on PhotoKit's queue | See `skills/isolation-inheritance-diag.md` | | Actor reentrancy / stale state across await | See `skills/isolation-inheritance-diag.md` | | Swift Concurrency Instruments template | See `skills/concurrency-profiling.md` | | Actor contention diagnosis | See `skills/concurrency-profiling.md` | | Thread pool exhaustion | See `skills/concurrency-profiling.md` |
## Decision Tree
```dot digraph concurrency { start [label="Concurrency task" shape=ellipse]; what [label="What do you need?" shape=diamond];
start -> what; what -> "skills/swift-concurrency.md" [label="async/await, actors,\nSendable, data races,\nSwift 6 migration"]; what -> "skills/swift-concurrency-ref.md" [label="API syntax lookup\n(TaskGroup, AsyncStream,\ncontinuations, migration)"]; what -> "skills/synchronization.md" [label="Mutex, locks,\natomic types"]; what -> "skills/assume-isolated.md" [label="assumeIsolated,\n@preconcurrency"]; what -> "skills/isolation-inheritance-diag.md" [label="warning-free build crashes\n_dispatch_assert_queue_fail\n_swift_task_checkIsolatedSwift"]; what -> "skills/concurrency-profiling.md" [label="profile async perf,\nactor contention"]; } ```
1. Data races / actor isolation / @MainActor / Sendable / Swift 6 migration? → `skills/swift-concurrency.md` 1a. Need specific API syntax (actor definition, TaskGroup, AsyncStream, continuations)? → `skills/swift-concurrency-ref.md` 1b. NotificationCenter observer, `userInfo` casting, or Sendable errors unpacking a notification? → `skills/swift-concurrency-ref.md` (Typed Notifications — `MainActorMessage`/`AsyncMessage`, iOS 26+) 2. Writing async/await code? → `skills/swift-concurrency.md` 3. assumeIsolated / @preconcurrency? → `skills/assume-isolated.md` 3a. Warning-free Swift 6 build that crashes in production with `_dispatch_assert_queue_fail` or `_swift_task_checkIsolatedSwift`? → `skills/isolation-inheritance-diag.md` 4. Mutex / lock / synchronization? → `skills/synchronization.md` 5. Profile async performance / actor contention? → `skills/concurrency-profiling.md` 6. Value type / ARC / generic optimization? → See axiom-performance (skills/swift-performance.md) 7. borrowing / consuming / ~Copyable? → See axiom-swift (skills/ownership-conventions.md) 8. Combine / @Published / AnyCancellable / reactive streams? → See axiom-uikit (skills/combine-patterns.md) 9. Want automated concurrency scan? → concurrency-auditor (Agent)
#### Concurrency in practice - HealthKit queries with Swift Concurrency (canonical bridging example) → See axiom-health (skills/queries.md)
## Conflict Resolution
**concurrency vs axiom-performance**: When app freezes or feels slow: 1. **Try concurrency FIRST** — Main thread blocking is the #1 cause of UI freezes. Check for synchronous work on @MainActor before profiling. 2. **Only use axiom-performance** if concurrency fixes don't help — Profile after ruling out obvious blocking. 3. **To pin a specific freeze to app code**, see the Hang Window Workflow in axiom-performance (skills/hang-diagnostics.md) — re-scope `xcprof analyze` to the hang window with `--start-ms/--end-ms --user-binary` to surface the app-owned frame on the main thread.
**concurrency vs axiom-build**: When seeing Swift 6 concurrency errors: - **Use concurrency, NOT axiom-build** — Concurrency errors are CODE issues, not environment issues.
**concurrency vs axiom-data**: When concurrency errors involve Core Data or SwiftData: - Core Data threading (NSManagedObjectContext thread confinement) → **use axiom-data first** - SwiftData + @MainActor ModelContext → **use concurrency** - General "background saves losing data" → **use axiom-data first** - GRDB Sendable patterns (struct records, `databaseSelection` as computed property, Swift 6 conformance) → See axiom-data (skills/grdb-performance.md) §8
## Critical Patterns
**Swift Concurrency** (`skills/swift-concurrency.md`): - Progressive journey: single-threaded → async → concurrent → actors - @concurrent attribute for forced background execution - Isolated conformances, main actor mode - 12 copy-paste patterns including delegate value capture, weak self in Tasks - Comprehensive decision tree for 7 common error messages
**API Reference** (`skills/swift-concurrency-ref.md`): - Actor definition, reentrancy, global actors, nonisolated - Sendable patterns, @unchecked Sendable, sending parameter - Task/TaskGroup/cancellation, async let, withDiscardingTaskGroup - AsyncStream, continuations, buffering policies - Isolation patterns (#isolation, @preconcurrency, nonisolated(unsafe)) - DispatchQueue/DispatchGroup/completion handler migration
**Synchronization** (`skills/synchronization.md`): - Mutex (iOS 18+), OSAllocatedUnfairLock (iOS 16+), Atomic types - Lock vs actor decision tree - Danger patterns: locks across await, semaphores in async context
**Profiling** (`skills/concurrency-profiling.md`): - Swift Concurrency Instruments template - Diagnosing main thread blocking, actor contention, thread pool exhaustion - Safe vs unsafe primitives for cooperative pool
**Runtime Isolation Crashes** (`skills/isolation-inheritance-diag.md`): - `_dispatch_assert_queue_fail` and `_swift_task_checkIsolatedSwift` signatures - Closure isolation inheritance (Core Data `perform`, Combine `.map`, NotificationCenter `.sink`) - Delegate method isolation inheritance (CLLocationManager, NSDocument, AVAudioPlayerDelegate, WKNavigationDelegate) - `MainActor.assumeIsolated` misuse - Actor reentrancy state staleness
## Automated Scanning
**Concurrency audit** → Launch `concurrency-auditor` agent or `/axiom:audit concurrency` (5-phase semantic audit: maps isolation architecture, detects 8 anti-patterns, reasons about missing concurrency patterns, correlates compound risks, scores Swift 6.4 readiness)
## Anti-Rationalization
| Thought | Reality | |---------|---------| | "Just add @MainActor and it'll work" | @MainActor has isolation inheritance rules. `skills/swift-concurrency.md` covers all patterns. | | "I'll use nonisolated(unsafe) to silence the warning" | Silencing warnings hides data races. `skills/swift-concurrency.md` shows the safe pattern. | | "It's just one async call" | Even single async calls have cancellation and isolation implications. | | "I know how actors work" | Actor reentrancy and isolation rules changed in Swift 6.2. | | "I'll fix the Sendable warnings later" | Sendable violations cause runtime crashes. Fix them now. | | "My Swift 6 build has zero warnings, so isolation is correct" | Static checking can't see SDK callbacks. Runtime checks crash anyway. `skills/isolation-inheritance-diag.md`. | | "I'll wrap the crash in `MainActor.assumeIsolated`" | `assumeIsolated` is a runtime trap, not a silencer. Wrong assumption = crash. | | "Combine is dead, just use async/await" | Combine has no deprecation notice. Rewriting working pipelines wastes time. See See axiom-uikit (skills/combine-patterns.md). | | "I'll use @unchecked Sendable to silence this" | You're hiding a data race from the compiler. It will crash in production. | | "This async function runs on a background thread" | `async` suspends without blocking but resumes on the *same actor*. Use `@concurrent` to force background. |
## Example Invocations
User: "I'm getting 'data race' errors in Swift 6" → Read: `skills/swift-concurrency.md`
User: "How do I use @MainActor correctly?" → Read: `skills/swift-concurrency.md`
User: "How do I create a TaskGroup?" → Read: `skills/swift-concurrency-ref.md`
User: "What's the AsyncStream API?" → Read: `skills/swift-concurrency-ref.md`
User: "How do I use assumeIsolated?" → Read: `skills/assume-isolated.md`
User: "Should I use Mutex or actor?" → Read: `skills/synchronization.md`
User: "My async code is slow, how do I profile it?" → Read: `skills/concurrency-profiling.md`
User: "My warning-free Swift 6 build crashes in production with _dispatch_assert_queue_fail" → Read: `skills/isolation-inheritance-diag.md`
User: "Core Data `context.perform` crashes inside an @MainActor view model" → Read: `skills/isolation-inheritance-diag.md`
User: "CLLocationManager delegate method is crashing with _swift_task_checkIsolatedSwift" → Read: `skills/isolation-inheritance-diag.md`
User: "My app is slow due to unnecessary copying" → See axiom-performance (skills/swift-performance.md)
User: "Check my code for Swift 6 concurrency issues" → Invoke: `concurrency-auditor` agent
Source provenance
Decision snapshot
1,146 GitHub stars
Audit
Install and adoption review
Agent-proven evidence
Outcome reports after resolve, review, install, and one narrow run.
No agent outcome data yet. The first agent run can report success, setup needs, risk blocks, failure, or not-relevant through /api/agent/outcome.
Install
Free and open source. Review the report before installing into production agents.
Growth loop
Scenario-led draft for axiom-concurrency, ready for a manual X post.
axiom-concurrency: Use when writing ANY async code, actors, threads, or seeing ANY concurrency error. Covers Swi... 1.1K stars https://www.openagentskill.com/skills/charleswiltgen-axiom-concurrency?ref=x
Listing + install path for axiom-concurrency: https://www.openagentskill.com/skills/charleswiltgen-axiom-concurrency?ref=x Install: npx skills add CharlesWiltgen/Axiom --skill axiom-concurrency
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[](https://www.openagentskill.com/skills/charleswiltgen-axiom-concurrency?ref=github&utm_source=github&utm_medium=referral&utm_campaign=creator_badge)
[](https://www.openagentskill.com/skills/charleswiltgen-axiom-concurrency/audit)
[](https://www.openagentskill.com/skills/charleswiltgen-axiom-concurrency?ref=github&utm_source=github&utm_medium=referral&utm_campaign=creator_badge)CharlesWiltgen
@charleswiltgen
Share whether this skill looks useful for your agent workflow. Aggregated feedback improves rankings over time.
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Bring data to life with SVG, Canvas and HTML. :bar_chart::chart_with_upwards_trend::tada:
113.1K StarsScientific Agent Skills
Turn any AI agent into an AI Scientist. The #1 Agent Skills library for science, used by 160,000+ scientists worldwide. 140 ready-to-use skills plus 100+ scientific databases covering biology, chemistry, medicine, and drug discovery. Compatible with Cursor, Claude Code, Codex, Pi, Antigravity, and the open Agent Skills standard.
33.5K StarsSuperset
Apache Superset is a Data Visualization and Data Exploration Platform
74.7K StarsPermission surface
shell or command execution, filesystem or document access
Agent outcomes
No agent outcome data yet
Docs
Strong README/SKILL.md context
Risk summary
Install readiness
Permission surface
shell or command execution, filesystem or document access
Agent outcomes
No agent outcome data yet
Docs
Strong README/SKILL.md context
Risk summary
Install readiness
Permission surface
shell or command execution, filesystem or document access
Agent outcomes
No agent outcome data yet
Docs
Strong README/SKILL.md context
Risk summary
Install readiness
Permission surface
shell or command execution, filesystem or document access
Agent outcomes
No agent outcome data yet
Docs
Strong README/SKILL.md context
Risk summary
Install readiness