The same file is also on GitHub Releases: Knight.dmg (identical bytes — check both SHA-256s against each other)

Install in three steps

1 · Open the DMG, drag the app to Applications

Double-click HeadlessKnightMaster-1.6.dmg. The app is on the left of the window, the Applications folder on the right. Drag it across, let it copy, close the window.

2 · First launch: right-click → Open

The app has no Apple Developer signature and isn't notarized, so macOS blocks it the first time with “cannot verify developer”. Nothing is broken.

In Applications, right-click the icon → Open → confirm in the dialog. Normal double-click from then on.

Heads-up: the app's own UI is currently in Chinese. English support is on the way.

3 · Authorize once, exactly once

Changing system sleep settings needs admin rights. On first launch, click “Authorize & Install” and enter your login password — used once, never asked again.

A notification permission prompt follows. Denying is fine — you just won't see the Enhanced Mode banner; core features are unaffected.

After install: Enhanced Mode

It's on by default. If the machine gets woken by an accidental press while you're out and nobody's around, it pushes it back to sleep. To turn it off: Settings → Enhanced Mode inside the app.

Specifically: once the machine has been continuously awake for 5 minutes, it forces sleep, with a 30-second countdown you can cancel first. It never acts while a display is plugged in, or while someone is logged in remotely.

If your machine's built-in display has been physically removed, also tick “No built-in display” in Settings — otherwise the phantom display macOS reports will be taken as “somebody's at the machine”, and it won't sleep even unplugged.

One thing no software can fix: a backpack squeezing the keyboard or trackpad wakes a just-slept machine — that's hardware input, no app can intercept it. For a physical fix, give it a barrier: an A-panel crystal shell, or a 3D-printed cover plate over keyboard and trackpad.

Verify the download

To confirm the file wasn't tampered with, compare the checksum in Terminal:

shasum -a 256 ~/Downloads/HeadlessKnightMaster-1.6.dmg

The output should match this exactly:

b0c959493e138bcfd051612ddf9f11640b284d0aa74c4813c5c634e816441bb4

System requirements

OS: macOS 13 Ventura or later
Architecture: Apple Silicon (arm64)
Disk: ~1.5 MB
Permissions: Admin password (once), notifications (optional), Bluetooth (optional)
Network: None. The app runs fully offline

Uninstall

Drag the app to the Trash, then run:

sudo rm -f /Library/PrivilegedHelperTools/com.headlessknight.helper \
  /Library/LaunchDaemons/com.headlessknight.helper.plist
sudo rm -rf ~/Library/Application\ Support/HeadlessKnightMaster
sudo rm -f ~/Library/LaunchAgents/com.headlessknight.app.plist

Bluetooth, sharing services and Time Machine changes are all restored when you tap “Done” normally inside the app. If you never did, turn Bluetooth back on and re-enable the services by hand.

Older versions

1.6 is current. Earlier builds had no public download channel, so only the latest is offered here. See the changelog for history.