Swift Concurrency Expert

Swift Concurrency review and remediation for Swift 6.2+. Use when asked to review Swift Concurrency usage, improve concurrency compliance, or fix Swift concurrency compiler errors in a feature or file.

Security Scan

The skill is an instruction-only Swift Concurrency code-review/remediation helper whose requirements and instructions are consistent with its stated purpose and do not request unrelated credentials or installs.

Purpose & Capability

Name and description match the content of SKILL.md and the included Swift concurrency references; there are no extraneous environment variables, binaries, or installs required that would be unrelated to a code-review/remediation skill.

Instruction Scope

Runtime instructions are narrowly focused on capturing compiler diagnostics, identifying actor contexts, and making targeted code changes (actor annotations, Sendable fixes, moving work to actors/@concurrent). There are no directives to read unrelated system files, exfiltrate data, or contact external endpoints.

Install Mechanism

No install spec or code files are present (instruction-only), so nothing will be downloaded or written to disk by the skill itself.

Credentials

The skill declares no required environment variables, credentials, or config paths; that is proportionate for a code-review advisory skill.

Persistence & Privilege

Skill is not always-enabled and does not request persistent system presence; autonomous invocation is allowed by platform default but there are no other elevated privileges requested.

Assessment

This is an instruction-only helper for reviewing and fixing Swift concurrency issues and appears internally consistent. Before installing or invoking: (1) remember the skill gives the agent guidance to modify code — review any proposed edits before applying them; (2) there are no requested credentials or downloads from the skill itself, but ensure your agent environment policies prevent accidental external transmission of your source code if that is a concern; (3) the content is copied/attributed—if license/origin matters for your project, verify suitability. Overall the skill looks appropriate for its stated purpose.

Attribution: copied from @Dimillian’s Dimillian/Skills (2025-12-31).

Overview

Review and fix Swift Concurrency issues in Swift 6.2+ codebases by applying actor isolation, Sendable safety, and modern concurrency patterns with minimal behavior changes.

Workflow

1. Triage the issue

• Capture the exact compiler diagnostics and the offending symbol(s).
• Identify the current actor context (@MainActor, actor, nonisolated) and whether a default actor isolation mode is enabled.
• Confirm whether the code is UI-bound or intended to run off the main actor.

2. Apply the smallest safe fix

Prefer edits that preserve existing behavior while satisfying data-race safety.

Common fixes:

• UI-bound types: annotate the type or relevant members with @MainActor.
• Protocol conformance on main actor types: make the conformance isolated (e.g., extension Foo: @MainActor SomeProtocol).
• Global/static state: protect with @MainActor or move into an actor.
• Background work: move expensive work into a @concurrent async function on a nonisolated type or use an actor to guard mutable state.
• Sendable errors: prefer immutable/value types; add Sendable conformance only when correct; avoid @unchecked Sendable unless you can prove thread safety.

Reference material

• See references/swift-6-2-concurrency.md for Swift 6.2 changes, patterns, and examples.
• See references/swiftui-concurrency-tour-wwdc.md for SwiftUI-specific concurrency guidance.