Capswitch

A small native macOS menu-bar app that uses Caps Lock to switch to the next enabled keyboard input source.

Behavior

• Plain Caps: switch once on release.
• Caps+Option in either order: preserve real Caps Lock.
• Stock Caps/input-source events are suppressed.
• The app has no Dock icon and reports Accessibility permission in its menu.

Build on macOS

The Linux RSB host cannot compile AppKit or run Swift/XCTest. On macOS 14+ with Apple's Command Line Tools installed:

xcode-select --install
task bundle
open build/Capswitch.app

No Xcode project or full Xcode.app is required.

Grant the app access at System Settings → Privacy & Security → Accessibility. Keep the bundle identifier and installation path stable so macOS can retain the permission.

Development commands

task lint
task test
task build
task bundle
task clean
task verify

The authoritative checks are task test and task bundle on macOS. Linux runs only host-independent checks and reports the missing Swift/macOS toolchain explicitly.