# swift-concurrency-pro

> Claude/Codex skill by [@twostraws](https://omgskills.com/library/twostraws/index.md) · 520 stars · Updated 2026-05-17

Reviews Swift code for concurrency correctness, modern API usage, and common async/await pitfalls. Use when reading, writing, or reviewing Swift concurrency code.

## Install

```sh
git clone https://github.com/twostraws/Swift-Concurrency-Agent-Skill /tmp/Swift-Concurrency-Agent-Skill && ln -s /tmp/Swift-Concurrency-Agent-Skill/swift-concurrency-pro ~/.claude/skills/swift-concurrency-pro
```

## From README

Core Instructions Target Swift 6.2 or later with strict concurrency checking. If code spans multiple targets or packages, compare their concurrency build settings before assuming behavior should match. Prefer structured concurrency (task groups) over unstructured (Task {}). Prefer Swift concurrency over Grand Central Dispatch for new code. GCD is still acceptable in low-level code, framework interop, or performance-critical synchronous work where queues and locks are the right tool – don't flag these as errors. If an API offers both async/await and closure-based variants, always prefer async/await. Do not introduce third-party concurrency frameworks without asking first. Do not suggest @unchecked Sendable to fix compiler errors. It silences the diagnostic without fixing the underlying race. Prefer actors, value types, or sending parameters instead. The only legitimate use is for types with internal locking that are provably thread-safe. Output Format Organize findings by file.

## Links

- HTML page: https://omgskills.com/skills/twostraws/swift-concurrency-agent-skill/swift-concurrency-pro/
- GitHub: https://github.com/twostraws/Swift-Concurrency-Agent-Skill
- Author: [@twostraws](https://omgskills.com/library/twostraws/index.md)

## More skills by this author

- [swiftui-pro](https://omgskills.com/skills/twostraws/swiftui-agent-skill/swiftui-pro/index.md) — Comprehensively reviews SwiftUI code for best practices on modern APIs, maintainability, and performance.
   - [@twostraws](https://omgskills.com/library/twostraws/index.md) · 4.6k stars
- [swiftui-pro](https://omgskills.com/skills/twostraws/swiftui-agent-skill/swiftui-pro/skills/swiftui-pro/index.md) — Comprehensively reviews SwiftUI code for best practices on modern APIs, maintainability, and performance.
   - [@twostraws](https://omgskills.com/library/twostraws/index.md) · 4.5k stars
- [swift-testing-pro](https://omgskills.com/skills/twostraws/swift-testing-agent-skill/swift-testing-pro/index.md) — Writes, reviews, and improves Swift Testing code using modern APIs and best practices.
   - [@twostraws](https://omgskills.com/library/twostraws/index.md) · 422 stars