Build macOS Apps - Professional Mac Development

Expert guidance for building native macOS apps using Swift, SwiftUI, and AppKit with CLI-first workflow.

Core Principles

1. Prove, Don't Promise

Never say "this should work." Always verify:

xcodebuild -scheme AppName build
xcodebuild -scheme AppName test
open ./build/Build/Products/Debug/AppName.app

2. Tests for Correctness, Eyes for Quality

Tests verify correctness. Users verify desirability.

3. Report Outcomes, Not Code

✅ Good: "Fixed memory leak. 0 leaks, stable for 5 minutes." ❌ Bad: "Refactored DataService to use async/await"

4. Small Steps, Always Verified

Change → Verify → Report → Next change

5. Ask Before, Not After

Clarify requirements before building.

6. Always Leave It Working

Every stop = working state.

---

Verification Loop

After every change:

xcodebuild -scheme AppName build
xcodebuild -scheme AppName test
open ./build/Build/Products/Debug/AppName.app

---

macOS App Types

Document-Based

@main
struct MyApp: App {
    var body: some Scene {
        DocumentGroup(newDocument: MyDocument()) { file in
            ContentView(document: file.$document)
        }
    }
}

Menu Bar Apps

class AppDelegate: NSObject, NSApplicationDelegate {
    var statusItem: NSStatusItem?
    func applicationDidFinishLaunching(_ notification: Notification) {
        statusItem = NSStatusBar.system.statusItem(withLength: NSStatusItem.variableLength)
    }
}

---

SwiftUI + AppKit

struct MyAppKitView: NSViewRepresentable {
    func makeNSView(context: Context) -> NSView { /* ... */ }
    func updateNSView(_ nsView: NSView, context: Context) { /* ... */ }
}

---

CLI Commands

# Build
xcodebuild -scheme AppName build

# Test
xcodebuild test -scheme AppName

# Archive
xcodebuild archive -scheme AppName -archivePath ./App.xcarchive

# Code sign
codesign --force --sign "Developer ID" --timestamp --options runtime ./AppName.app

# Notarize
xcrun notarytool submit AppName.dmg --keychain-profile "AC_PASSWORD" --wait
xcrun stapler staple AppName.dmg

---

Remember

1. Prove it works - build, test, launch
2. Small verified steps
3. Ask first
4. Report outcomes
5. Leave it working
6. Tests for logic, eyes for UI