swift-concurrency

Original：🇺🇸 English

Translated

Swift Concurrency patterns — async/await, actors, tasks, Sendable conformance. Use when writing async/await code, implementing actors, working with structured concurrency, or ensuring data race safety.

2installs

Sourceravnhq/ai-toolkit

Added on2026-02-24

NPX Install

npx skill4agent add ravnhq/ai-toolkit swift-concurrency

SKILL.md Content

View Translation Comparison →

Swift Concurrency Patterns

Expert guidance on Swift Concurrency best practices covering async/await, actors, tasks, Sendable, threading, memory management, testing, and migration strategies.

Rules

Core Swift Concurrency rules extracted as discrete, high-impact patterns. See rules index for the full list organized by:

Async/Await Patterns - Never add dummy suspension points to silence warnings
Actor Isolation - Use actors for data-race safety with compiler verification
Task Lifecycle - Understand task cancellation and structured concurrency
Sendable Conformance - Require Sendable for crossing concurrency boundaries
Testing - Patterns for testing async concurrent code without flaky tests

References

See references/swift-concurrency.md for comprehensive guidance organized by:

Async/Await Fundamentals - Core patterns, error handling, parallel execution
Tasks & Structured Concurrency - Task lifecycle, cancellation, task groups
Actors & Isolation - Actor isolation, suspension points, state safety
Sendable & Data Safety - Sendable conformance, data races, safe captures
Threading & Execution - Execution contexts, isolation domains
Memory Management - Retain cycles, weak references, task lifecycle
Testing Concurrency - Async test patterns, Swift Testing integration
Migration & Interop - Strict concurrency migration, legacy interop

Examples

Positive Trigger

User: "Refactor callback-based network code to async/await with actor isolation."

Expected behavior: Use

swift-concurrency

guidance, follow its workflow, and return actionable output.

Non-Trigger

User: "Refactor CSS grid layout for mobile breakpoints."

Expected behavior: Do not prioritize

swift-concurrency

; choose a more relevant skill or proceed without it.

Troubleshooting

Skill Does Not Trigger

Error: The skill is not selected when expected.
Cause: Request wording does not clearly match the description trigger conditions.
Solution: Rephrase with explicit domain/task keywords from the description and retry.

Guidance Conflicts With Another Skill

Error: Instructions from multiple skills conflict in one task.
Cause: Overlapping scope across loaded skills.
Solution: State which skill is authoritative for the current step and apply that workflow first.

Output Is Too Generic

Error: Result lacks concrete, actionable detail.
Cause: Task input omitted context, constraints, or target format.
Solution: Add specific constraints (environment, scope, format, success criteria) and rerun.

Workflow

Identify whether the request clearly matches
```
swift-concurrency
```
scope and triggers.
Apply the skill rules and referenced guidance to produce a concrete result.
Validate output quality against constraints; if gaps remain, refine once with explicit assumptions.