LeftRightMouse

LeftRightMouse is a small macOS utility for switching mouse left/right button behavior in real time.

Behavior

• Runs as a menu bar utility without a Dock icon or control-panel window.
• Shows the current mode with a mirrored cursor-style menu bar icon.
• Uses the macOS IOHIDSetMouseButtonMode system setting to switch mouse left/right button behavior immediately, with hidutil used only as a cleanup/fallback path.
• Mirrors the system pointer cursors while left-handed mode is active.
• Includes a launch-at-login toggle backed by SMAppService.mainApp.
• Does not require Accessibility/Input Monitoring permission and does not show confirmation dialogs when switching modes.
• Does not require logging out or restarting macOS.
• Does not show a confirmation dialog when switching modes.

Build

Open LeftRightMouse.xcodeproj in Xcode, or run:

xcodebuild -project LeftRightMouse.xcodeproj -scheme LeftRightMouse -configuration Debug -derivedDataPath DerivedData build

The project uses local ad-hoc signing by default so it can build without an Apple Developer Team.