Agent skill

Swift Actor Persistence

Swiftでactorを使用してスレッドセーフなデータ永続化を実装する——メモリキャッシュとファイルバックドストレージを組み合わせ、設計によってデータ競合を排除する。

MITAuto-check passedMobile

Install Swift Actor Persistence

skills CLI

$ npx skills add affaan-m/ECC --skill swift-actor-persistence -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI

$ gh skill install affaan-m/ECC swift-actor-persistence --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy

$ git clone --depth 1 https://github.com/affaan-m/ECC.git skills-src && mkdir -p .claude/skills && cp -r skills-src/docs/ja-JP/skills/swift-actor-persistence .claude/skills/swift-actor-persistence && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Paste into Claude Code

Install the "swift-actor-persistence" agent skill from https://github.com/affaan-m/ECC/tree/main/docs/ja-JP/skills/swift-actor-persistence into .claude/skills/swift-actor-persistence/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "swift-actor-persistence", then confirm the skill loads.

Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

$skill-installer

$skill-installer install https://github.com/affaan-m/ECC/tree/main/docs/ja-JP/skills/swift-actor-persistence

Type this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.

skills CLI

$ npx skills add affaan-m/ECC --skill swift-actor-persistence -a codex

Project install goes to .agents/skills/; add -g for ~/.codex/skills/.

GitHub CLI

$ gh skill install affaan-m/ECC swift-actor-persistence --agent codex

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/affaan-m/ECC.git skills-src && mkdir -p .agents/skills && cp -r skills-src/docs/ja-JP/skills/swift-actor-persistence .agents/skills/swift-actor-persistence && rm -rf skills-src

Use ~/.agents/skills/ instead of .agents/skills for a personal install.

Codex skills documentation · loads skills from .agents/skills/

Paste into Codex

Install the "swift-actor-persistence" agent skill from https://github.com/affaan-m/ECC/tree/main/docs/ja-JP/skills/swift-actor-persistence into .agents/skills/swift-actor-persistence/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "swift-actor-persistence", then confirm the skill loads.

Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add affaan-m/ECC --skill swift-actor-persistence -a cursor

Project install goes to .agents/skills/; add -g for ~/.cursor/skills/.

GitHub CLI

$ gh skill install affaan-m/ECC swift-actor-persistence --agent cursor

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/affaan-m/ECC.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/docs/ja-JP/skills/swift-actor-persistence .cursor/skills/swift-actor-persistence && rm -rf skills-src

Use ~/.cursor/skills/ instead of .cursor/skills for a personal install.

Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/

Paste into Cursor

Install the "swift-actor-persistence" agent skill from https://github.com/affaan-m/ECC/tree/main/docs/ja-JP/skills/swift-actor-persistence into .cursor/skills/swift-actor-persistence/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "swift-actor-persistence", then confirm the skill loads.

Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

gemini skills install

$ gemini skills install https://github.com/affaan-m/ECC.git --path docs/ja-JP/skills/swift-actor-persistence

--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.

skills CLI

$ npx skills add affaan-m/ECC --skill swift-actor-persistence -a gemini-cli

Project install goes to .agents/skills/; add -g for ~/.gemini/skills/.

GitHub CLI

$ gh skill install affaan-m/ECC swift-actor-persistence --agent gemini-cli

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/affaan-m/ECC.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/docs/ja-JP/skills/swift-actor-persistence .gemini/skills/swift-actor-persistence && rm -rf skills-src

Use ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.

Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/

Paste into Gemini CLI

Install the "swift-actor-persistence" agent skill from https://github.com/affaan-m/ECC/tree/main/docs/ja-JP/skills/swift-actor-persistence into .gemini/skills/swift-actor-persistence/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "swift-actor-persistence", then confirm the skill loads.

Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

GitHub CLI

$ gh skill install affaan-m/ECC swift-actor-persistence

Installs for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).

skills CLI

$ npx skills add affaan-m/ECC --skill swift-actor-persistence -a github-copilot

Project install goes to .agents/skills/; add -g for ~/.copilot/skills/.

Manual copy

$ git clone --depth 1 https://github.com/affaan-m/ECC.git skills-src && mkdir -p .github/skills && cp -r skills-src/docs/ja-JP/skills/swift-actor-persistence .github/skills/swift-actor-persistence && rm -rf skills-src

Use ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.

GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/

Paste into GitHub Copilot

Install the "swift-actor-persistence" agent skill from https://github.com/affaan-m/ECC/tree/main/docs/ja-JP/skills/swift-actor-persistence into .github/skills/swift-actor-persistence/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "swift-actor-persistence", then confirm the skill loads.

GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add affaan-m/ECC --skill swift-actor-persistence -a opencode

OpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.

GitHub CLI

$ gh skill install affaan-m/ECC swift-actor-persistence --agent opencode

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/affaan-m/ECC.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/docs/ja-JP/skills/swift-actor-persistence .opencode/skills/swift-actor-persistence && rm -rf skills-src

Use ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.

OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/

Paste into OpenCode

Install the "swift-actor-persistence" agent skill from https://github.com/affaan-m/ECC/tree/main/docs/ja-JP/skills/swift-actor-persistence into .opencode/skills/swift-actor-persistence/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "swift-actor-persistence", then confirm the skill loads.

OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

Facts

Skill name: swift-actor-persistence
GitHub stars: 276k
Token cost: ~1.1k tokens
SKILL.md length: 74 words
Files: 1
Skills in repo: 683
Repo updated: Oct 10, 2026
First seen: Oct 7, 2026
Licence: MIT

At a glance

Tasks that involve iOS development
SKILL.md covers 起動条件, コアパターン, 重要な設計上の決定 and ベストプラクティス, plus 2 more sections
Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md

What it does

Swift Actor Persistence is an agent skill from affaan-m/ECC. Swiftでactorを使用してスレッドセーフなデータ永続化を実装する——メモリキャッシュとファイルバックドストレージを組み合わせ、設計によってデータ競合を排除する。

Its SKILL.md is about 1.1k tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.

It sits in Mobile, covering iOS development. The repository describes itself as: The agent harness performance optimization system. Skills, instincts, memory, security, and research-first development for Claude Code, Codex, Opencode, Cursor and beyond. The licence is MIT.

When your agent uses it

Tasks that involve iOS development

Example prompts

“/swift-actor-persistence”

What it can do on your machine

Read from SKILL.md and the folder at commit 4eb71d9. It shows what the files ask for, not the result of running them.

Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md (its code samples are swift).
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Swift Actor Persistence loads about 1.1k tokens when it runs. Until then it costs about 27 tokens; SKILL.md has 74 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~27
When it runs · the whole SKILL.md, loaded when a task matches: ~1.1k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from affaan-m/ECC at commit 4eb71d9, republished under its MIT licence (© affaan-m). 74 words, ~1,057 tokens.

Download SKILL.mdSave it as .claude/skills/swift-actor-persistence/SKILL.md (or your agent's skills folder).

name: swift-actor-persistence
description: Swiftでactorを使用してスレッドセーフなデータ永続化を実装する——メモリキャッシュとファイルバックドストレージを組み合わせ、設計によってデータ競合を排除する。
origin: ECC

スレッドセーフな永続化のための Swift Actor

Swiftのactorを使用してスレッドセーフなデータ永続化レイヤーを構築するパターン。メモリキャッシュとファイルバックドストレージを組み合わせ、actorモデルを活用してコンパイル時にデータ競合を排除する。

起動条件

Swift 5.5以降でデータ永続化レイヤーを構築する場合
共有可変状態へのスレッドセーフアクセスが必要な場合
手動の同期（ロック、DispatchQueue）を排除したい場合
ローカルストレージを持つオフラインファースとアプリを構築する場合

コアパターン

Actorベースのリポジトリ

Actorモデルはシリアライズされたアクセスを保証する——コンパイラによって強制されるデータ競合なし。

swift

public actor LocalRepository<T: Codable & Identifiable> where T.ID == String {
    private var cache: [String: T] = [:]
    private let fileURL: URL

    public init(directory: URL = .documentsDirectory, filename: String = "data.json") {
        self.fileURL = directory.appendingPathComponent(filename)
        // Synchronous load during init (actor isolation not yet active)
        self.cache = Self.loadSynchronously(from: fileURL)
    }

    // MARK: - Public API

    public func save(_ item: T) throws {
        let previous = cache[item.id]
        cache[item.id] = item
        do {
            try persistToFile()
        } catch {
            // ディスク書き込み失敗時はキャッシュをロールバックして整合性を維持
            cache[item.id] = previous
            throw error
        }
    }

    public func delete(_ id: String) throws {
        let previous = cache[id]
        cache[id] = nil
        do {
            try persistToFile()
        } catch {
            // ディスク書き込み失敗時はキャッシュをロールバックして整合性を維持
            cache[id] = previous
            throw error
        }
    }

    public func find(by id: String) -> T? {
        cache[id]
    }

    public func loadAll() -> [T] {
        Array(cache.values)
    }

    // MARK: - Private

    private func persistToFile() throws {
        let data = try JSONEncoder().encode(Array(cache.values))
        try data.write(to: fileURL, options: .atomic)
    }

    private static func loadSynchronously(from url: URL) -> [String: T] {
        guard let data = try? Data(contentsOf: url),
              let items = try? JSONDecoder().decode([T].self, from: data) else {
            return [:]
        }
        return Dictionary(uniqueKeysWithValues: items.map { ($0.id, $0) })
    }
}

使い方

Actorの分離により、すべての呼び出しは自動的に非同期になる：

swift

let repository = LocalRepository<Question>()

// Read — fast O(1) lookup from in-memory cache
let question = await repository.find(by: "q-001")
let allQuestions = await repository.loadAll()

// Write — updates cache and persists to file atomically
try await repository.save(newQuestion)
try await repository.delete("q-001")

@Observable ViewModel との組み合わせ

swift

@Observable
final class QuestionListViewModel {
    private(set) var questions: [Question] = []
    private let repository: LocalRepository<Question>

    init(repository: LocalRepository<Question> = LocalRepository()) {
        self.repository = repository
    }

    func load() async {
        questions = await repository.loadAll()
    }

    func add(_ question: Question) async throws {
        try await repository.save(question)
        questions = await repository.loadAll()
    }
}

重要な設計上の決定

決定	理由
Actorを使用（クラス + ロックではなく）	コンパイラによって強制されるスレッド安全性、手動同期不要
メモリキャッシュ + ファイル永続化	キャッシュからの高速読み取り、ディスクへの永続的な書き込み
初期化時の同期ロード	非同期初期化の複雑さを回避
IDをキーとする辞書	識別子によるO(1)検索
ジェネリック `Codable & Identifiable`	あらゆるモデル型で再利用可能
アトミックなファイル書き込み（`.atomic`）	クラッシュ時の部分書き込みを防ぐ

ベストプラクティス

Actorの境界を越えるすべてのデータに Sendable 型を使用する
Actorのパブリックなアビリティを最小化する —— 永続化の詳細ではなく、ドメイン操作のみを公開する
.atomic 書き込みを使用する —— 書き込み中のアプリクラッシュによるデータ破損を防ぐ
init で同期的にロードする —— 非同期イニシャライザはローカルファイルに対するわずかな利点のために複雑さが増す
@Observable ViewModelと組み合わせる —— リアクティブなUI更新を実現する

避けるべきアンチパターン

Swiftの新しい並行処理コードでActorの代わりに DispatchQueue または NSLock を使用する
内部のキャッシュ辞書を外部の呼び出し元に公開する
初期化後にファイルURLを外部から変更可能にする（初期化時のみ設定を許可すること）
すべてのActor メソッド呼び出しが await であることを忘れる——呼び出し元は非同期コンテキストを処理する必要がある
Actor の分離をバイパスするために nonisolated を使用する（本末転倒）

使用場面

iOS/macOSアプリのローカルデータストレージ（ユーザーデータ、設定、キャッシュコンテンツ）
後でサーバーと同期するオフラインファーストアーキテクチャ
アプリの複数の部分から並行アクセスされる共有可変状態
DispatchQueue ベースのレガシーなスレッド安全機構を最新のSwift並行処理に置き換える

Files

Just SKILL.md in docs/ja-JP/skills/swift-actor-persistence of affaan-m/ECC.

Open the folder on GitHubat commit 4eb71d9

Compare with similar skills

Swift Actor Persistence next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Swift Actor Persistence compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
Swift Actor Persistence this skillaffaan-m/ECC	276k	—	~1.1k	Automated safety check: Pass	MIT	yesterday
Swiftui Protwostraws/SwiftUI-Agent-Skill	5.6k	2 repos	~1.5k	Automated safety check: Pass	MIT	3 days ago
Swiftui UI PatternsAFK-surf/OpenBridge	430	4 repos	~887	Automated safety check: Pass	MIT	4 mo ago
Swiftui Performance Auditharperreed/dotfiles	334	8 repos	~1.4k	Automated safety check: Pass	None	8 days ago
Swift Testing ExpertAvdLee/Swift-Testing-Agent-Skill	471	1 repos	~1.2k	Automated safety check: Pass	MIT	26 days ago
Hig Project Contextraintree-technology/hig-doctor	144	5 repos	~1.2k	Automated safety check: Pass	MIT	today

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Questions about Swift Actor Persistence

What does Swift Actor Persistence do?

Swiftでactorを使用してスレッドセーフなデータ永続化を実装する——メモリキャッシュとファイルバックドストレージを組み合わせ、設計によってデータ競合を排除する。. Swift Actor Persistence is an agent skill from affaan-m/ECC.

When should I use Swift Actor Persistence?

Swift Actor Persistence fits situations like: tasks that involve iOS development.

How do I install Swift Actor Persistence in Claude Code?

Run `npx skills add affaan-m/ECC --skill swift-actor-persistence -a claude-code`. Or copy the skill folder (docs/ja-JP/skills/swift-actor-persistence in affaan-m/ECC) into .claude/skills/swift-actor-persistence in your project. Claude Code loads it when a task matches its description.

How do I install Swift Actor Persistence in Codex?

Run `npx skills add affaan-m/ECC --skill swift-actor-persistence -a codex`. Or copy the skill folder (docs/ja-JP/skills/swift-actor-persistence in affaan-m/ECC) into .agents/skills/swift-actor-persistence in your project. Codex loads it when a task matches its description.

Can I use Swift Actor Persistence in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add affaan-m/ECC --skill swift-actor-persistence -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/swift-actor-persistence, .gemini/skills/swift-actor-persistence, .github/skills/swift-actor-persistence and .opencode/skills/swift-actor-persistence in your project.

What does Swift Actor Persistence need to run?

SKILL.md names no scripts, command-line tools or credentials: Swift Actor Persistence is instructions for the agent only.

Does Swift Actor Persistence access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is Swift Actor Persistence safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does Swift Actor Persistence use?

Swift Actor Persistence is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Swift Actor Persistence use?

About 1.1k tokens (SKILL.md is roughly 4.2k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.

What are the alternatives to Swift Actor Persistence?

Skills that share tags, products or a category with Swift Actor Persistence: Swiftui Pro (twostraws/SwiftUI-Agent-Skill, 5.6k stars), Swiftui UI Patterns (AFK-surf/OpenBridge, 430 stars), Swiftui Performance Audit (harperreed/dotfiles, 334 stars) and Swift Testing Expert (AvdLee/Swift-Testing-Agent-Skill, 471 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Swift Actor Persistence?

affaan-m (a GitHub user) maintains it in affaan-m/ECC, which has 276,111 GitHub stars. The repository holds 683 skills in this directory. The repository was last updated on October 10, 2026.

Source: affaan-m/ECC on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Install Swift Actor Persistence

Facts

At a glance

What it does

When your agent uses it

Example prompts

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

スレッドセーフな永続化のための Swift Actor

起動条件

コアパターン

Actorベースのリポジトリ

使い方

@Observable ViewModel との組み合わせ

重要な設計上の決定

ベストプラクティス

避けるべきアンチパターン

使用場面

Files

Compare with similar skills

Similar skills

More from affaan-m/ECC

Related

Questions about Swift Actor Persistence