iPhone Backup

Small macOS app: finds the newest local iPhone backup, packs it into a real .zip, and moves it into the OneDrive folder _iPhone-BU.

Layout

Path	What
Sources/iPhoneBackupApp.swift	the whole app (SwiftUI + AppKit, single file)
Info.plist	bundle metadata — CFBundleExecutable must stay iPhoneBackup
build.sh	compiles, assembles the .app, ad-hoc signs it
Tools/render-icon.swift	draws the icon with CoreGraphics
Tools/make-icon.sh	renders + resizes + packs Resources/AppIcon.icns
Resources/	AppIcon.icns and the 1024 px master PNG
build/	build output (throwaway, safe to delete)

Build

./build.sh              # -> build/iPhone Backup.app
./build.sh --install    # also copies to ~/Applications

Needs only the Command Line Tools (xcode-select -p), no full Xcode.

Quit the app before rebuilding — build.sh starts with rm -rf on the bundle, and pulling that out from under a running archive job is asking for trouble.

Icon

./Tools/make-icon.sh    # only after editing Tools/render-icon.swift

build.sh consumes the committed Resources/AppIcon.icns, so a normal build does not re-render. If Finder still shows the old icon after a rebuild, refresh the cache:

/System/Library/Frameworks/CoreServices.framework/Frameworks/LaunchServices.framework/Support/lsregister -f ~/Applications/"iPhone Backup.app"

Things that will bite you again

• -parse-as-library is required. Compiling a single .swift file that uses @main fails with "'main' attribute cannot be used in a module that contains top-level code" without it. Already in build.sh.
• An .app is a bundle, not a renamed binary. It needs Contents/MacOS/iPhoneBackup + Contents/Info.plist with a matching CFBundleExecutable + a signature. Missing any of those and it silently won't launch.
• Full Disk Access. Reading ~/Library/Application Support/MobileSync/Backup is TCC-protected. Grant it under Systemeinstellungen › Datenschutz & Sicherheit › Festplattenvollzugriff. The app is ad-hoc signed, so its identity changes on every rebuild — after ./build.sh --install you may have to remove and re-add the entry.
• ditto -c -k, not tar -czf. tar -czf out.zip writes a gzip tarball with a lying file extension. ditto -c -k --sequesterRsrc --keepParent writes a genuine zip64 archive.
• Stage locally, then move. The archive is built in ~/.iphone-backup-staging and only then moved into OneDrive — same volume, so it is an instant rename. Writing directly into OneDrive makes it upload a half-written 50 GB file.
• FileAttributeKey.size is an NSNumber. attrs[.size] as? Int64 is always nil; use (attrs[.size] as? NSNumber)?.int64Value.
• Check terminationStatus. An archiver that cannot report failure will happily leave a truncated file behind and claim success.

Ideas if you pick this up again

• Store-only mode (zip -0) for speed — iPhone backups barely compress (~2%).
• Retention: keep the N newest archives, delete older ones.
• Schedule it with a launchd LaunchAgent (not cron — a sleeping laptop misses cron).
• Verify the finished archive (ditto -V -x -k into /dev/null, or unzip -t).
• Proper Developer ID signing so the Full Disk Access grant survives rebuilds.