aradotso/skills/shichizip-macos-archiver

---
name: shichizip-macos-archiver
description: ShichiZip is a 7-Zip derivative for macOS built in Swift, providing archive creation, extraction, and management with native macOS integration.
triggers:
  - "how do I build ShichiZip"
  - "compress files with ShichiZip"
  - "extract archives on macOS with 7-zip"
  - "ShichiZip zstandard variant"
  - "build 7-zip for macOS Swift"
  - "ShichiZip xcodebuild commands"
  - "integrate ShichiZip into my app"
  - "ShichiZip mainline vs zstandard fork"
---

# ShichiZip macOS Archiver

> Skill by [ara.so](https://ara.so) — Daily 2026 Skills collection.

ShichiZip is a native macOS archive manager derived from 7-Zip, written in Swift. It provides a macOS-native UI and supports standard 7-Zip archive formats, with an optional Zstandard-enhanced fork variant for improved compression.

---

## What ShichiZip Does

- Opens, creates, and extracts archives in formats supported by 7-Zip (7z, zip, tar, gz, bz2, xz, rar, etc.)
- Provides a native macOS SwiftUI/AppKit interface
- Offers two build variants:
  - **Mainline**: Standard 7-Zip backend
  - **ZS (Zstandard)**: Fork with Zstandard compression support

---

## Requirements

- macOS (Apple Silicon recommended; `arm64` used in official build commands)
- Xcode (with command-line tools)
- `make`
- Swift toolchain

---

## Building ShichiZip

### Step 1: Clone the Repository

```bash
git clone https://github.com/idawnlight/ShichiZip.git
cd ShichiZip

Step 2: Build the Native Library

Mainline variant:

make lib-mainline

Zstandard fork variant:

make lib-zs

Step 3: Build the App with Xcode

Mainline app:

xcodebuild \
  -project ShichiZip.xcodeproj \
  -scheme ShichiZip \
  -configuration Debug \
  -arch arm64 \
  build

Zstandard variant app:

xcodebuild \
  -project ShichiZip.xcodeproj \
  -scheme ShichiZipZS \
  -configuration Debug \
  -arch arm64 \
  build

Build for Release

xcodebuild \
  -project ShichiZip.xcodeproj \
  -scheme ShichiZip \
  -configuration Release \
  -arch arm64 \
  build

---

Project Structure

ShichiZip/
├── ShichiZip.xcodeproj/    # Xcode project
├── ShichiZip/              # Swift app source
│   ├── AppDelegate.swift   # App entry point
│   ├── ContentView.swift   # Main SwiftUI view
│   └── ...
├── Makefile                # Library build targets
└── README.md

---

Schemes and Variants

| Scheme | Library Target | Description | |---------------|-----------------|------------------------------------| | ShichiZip | lib-mainline | Standard 7-Zip backend | | ShichiZipZS | lib-zs | Zstandard-enhanced fork |

Always match the make target to the Xcode scheme:

• make lib-mainline → -scheme ShichiZip
• make lib-zs → -scheme ShichiZipZS

---

Swift Integration Patterns

Opening an Archive (SwiftUI View Example)

import SwiftUI

struct ArchiveOpenView: View {
    @State private var selectedURL: URL? = nil
    @State private var showFilePicker = false

    var body: some View {
        Button("Open Archive") {
            showFilePicker = true
        }
        .fileImporter(
            isPresented: $showFilePicker,
            allowedContentTypes: [.archive, .zip],
            allowsMultipleSelection: false
        ) { result in
            switch result {
            case .success(let urls):
                selectedURL = urls.first
                if let url = selectedURL {
                    openArchive(at: url)
                }
            case .failure(let error):
                print("File picker error: \(error.localizedDescription)")
            }
        }
    }

    func openArchive(at url: URL) {
        // Pass URL to ShichiZip's archive handling layer
        print("Opening archive at: \(url.path)")
    }
}

Triggering Archive Extraction via Process (Shell Bridge)

If integrating with the 7-Zip CLI binary bundled in the app:

import Foundation

func extract(archivePath: String, destinationPath: String) {
    guard let binaryURL = Bundle.main.url(
        forResource: "7zz",
        withExtension: nil,
        subdirectory: "Binaries"
    ) else {
        print("7zz binary not found in bundle")
        return
    }

    let process = Process()
    process.executableURL = binaryURL
    process.arguments = ["x", archivePath, "-o\(destinationPath)", "-y"]

    let outputPipe = Pipe()
    let errorPipe = Pipe()
    process.standardOutput = outputPipe
    process.standardError = errorPipe

    do {
        try process.run()
        process.waitUntilExit()

        let outputData = outputPipe.fileHandleForReading.readDataToEndOfFile()
        let output = String(data: outputData, encoding: .utf8) ?? ""
        print("Output: \(output)")

        if process.terminationStatus != 0 {
            let errorData = errorPipe.fileHandleForReading.readDataToEndOfFile()
            let error = String(data: errorData, encoding: .utf8) ?? ""
            print("Error: \(error)")
        }
    } catch {
        print("Failed to run extraction: \(error)")
    }
}

Creating an Archive

func createArchive(inputPath: String, outputPath: String) {
    guard let binaryURL = Bundle.main.url(
        forResource: "7zz",
        withExtension: nil,
        subdirectory: "Binaries"
    ) else { return }

    let process = Process()
    process.executableURL = binaryURL
    // "a" = add to archive
    process.arguments = ["a", outputPath, inputPath]

    do {
        try process.run()
        process.waitUntilExit()
        print("Archive created at \(outputPath), exit: \(process.terminationStatus)")
    } catch {
        print("Failed to create archive: \(error)")
    }
}

Listing Archive Contents

func listArchiveContents(archivePath: String) -> [String] {
    guard let binaryURL = Bundle.main.url(
        forResource: "7zz",
        withExtension: nil,
        subdirectory: "Binaries"
    ) else { return [] }

    let process = Process()
    process.executableURL = binaryURL
    process.arguments = ["l", archivePath]

    let pipe = Pipe()
    process.standardOutput = pipe

    do {
        try process.run()
        process.waitUntilExit()
        let data = pipe.fileHandleForReading.readDataToEndOfFile()
        let output = String(data: data, encoding: .utf8) ?? ""
        return output.components(separatedBy: "\n").filter { !$0.isEmpty }
    } catch {
        print("Failed to list archive: \(error)")
        return []
    }
}

---

Common Makefile Targets

# Build the mainline 7-Zip library
make lib-mainline

# Build the Zstandard fork library
make lib-zs

# Clean build artifacts (if defined)
make clean

---

Xcode Build Flags Reference

| Flag | Description | |-------------------|--------------------------------------| | -project | Path to .xcodeproj | | -scheme | ShichiZip or ShichiZipZS | | -configuration | Debug or Release | | -arch | arm64 (Apple Silicon) or x86_64 | | build | Build action |

---

Troubleshooting

make lib-mainline fails with missing dependencies

• Ensure Xcode command-line tools are installed: xcode-select --install
• Verify you have internet access for any fetched dependencies during make

Xcode build fails: "No such scheme"

• Confirm you ran the correct make target before building
• Open ShichiZip.xcodeproj in Xcode and verify the scheme list matches

Binary not found at runtime

• Ensure the 7-Zip binary is included in the app bundle's Copy Files build phase
• Check Bundle.main.url(forResource:) path matches the actual bundle structure

Architecture mismatch

• If running on Intel Mac, replace -arch arm64 with -arch x86_64
• For universal binary: -arch arm64 -arch x86_64 (requires both library builds)

Permission denied on extraction

• Use NSOpenPanel or fileImporter to obtain security-scoped bookmarks before accessing user files
• Call url.startAccessingSecurityScopedResource() / url.stopAccessingSecurityScopedResource()

if url.startAccessingSecurityScopedResource() {
    defer { url.stopAccessingSecurityScopedResource() }
    extract(archivePath: url.path, destinationPath: destinationURL.path)
}

---

License

ShichiZip is licensed under LGPL-2.1, inherited from 7-Zip's licensing terms.