FreeSlapMac

I saw the trend that people were slapping their macs and I wanted to try it myself. I looked around and didn't quite find a free version that is also easy to install so I decided to create an open-source version of it.

I also added a new functionality to it called RageQuit which I'm currently working on, the idea is that it will lock your Mac and play a calming sound whenever it detects a sudden shock (for example smashing your table).

Feel free to try the app, I'd be happy to know if you encountred any bugs and have new ideas how we can make use of these snesors.

Have fun out there and don't break your Macs ;-).

I would appreciate a coffee.

#'''''''' A free, open menu-bar app inspired by slapmac.com. Slap your Apple Silicon MacBook, it yells back. Need a break? Hit Rage Quit and the Mac locks itself while a relaxing track plays.

Detection technique is borrowed from taigrr/spank: read the IMU accelerometer directly over IOKit HID, then run an STA/LTA + peak/MAD pipeline to distinguish a real impact from everyday vibration.

Apple Silicon only (M1 and newer). Requires macOS 14 (Sonoma) or later.

How it works

┌────────────────────────────┐     XPC (mach)      ┌──────────────────────────┐
│ com.freeslapmac.helper     │ ───── events ─────▶ │ FreeSlapMac.app          │
│ LaunchDaemon (runs as root)│                     │ SwiftUI menu-bar app     │
│ reads SPU accelerometer    │                     │ plays sounds, locks,     │
│ runs slap detector         │                     │ offers Rage Quit         │
└────────────────────────────┘                     └──────────────────────────┘

The GUI stays unprivileged. A tiny signed helper runs as root (via SMAppService.daemon) and streams slap events over XPC. Approve it once in System Settings → General → Login Items and it keeps running across reboots.

Project layout

Path	Purpose
App/	SwiftUI menu-bar app — FreeSlapMacApp.swift, MenuBarView.swift, SettingsView.swift, SlapEngine.swift, Info.plist, FreeSlapMac.entitlements
Helper/	Privileged daemon — main.swift, HIDSensor.swift, SlapDetector.swift, com.freeslapmac.helper.plist, Info.plist
Shared/	XPCProtocol.swift used by both targets
Resources/Sounds/Reactions/	Drop .mp3 reaction clips here (bundled into the app)
Resources/Sounds/Relax/	relax.mp3 played during Rage Quit
Tests/	SlapDetectorTests.swift (Swift Testing)
Packaging/build.sh	Compile + ad-hoc sign + build .dmg

Build

One-shot DMG

./Packaging/build.sh

Produces build/FreeSlapMac.dmg. Uses swiftc + hdiutil (or create-dmg if installed). Ad-hoc signed with identity -, no Apple Developer account required.

Run unit tests

swift test                     # requires Xcode (for Testing framework)

Opening in Xcode

Open the working directory with xed . — Xcode will index it. Create a workspace with two targets matching App/ and Helper/ if you want to use Xcode's build system end-to-end.

First run (for users of the DMG)

1. Mount FreeSlapMac.dmg, drag the app to Applications.
2. Ad-hoc signed apps are blocked by Gatekeeper the first time: Right-click the app → Open → Open Anyway.
3. The app asks permission to install its helper — approve in System Settings → General → Login Items.
4. Slap the chassis. Menu-bar icon turns solid when detection is active.

Permissions & hardware access

What	Why	How
IOKit HID (seize) on the motion accelerometer	Read impact samples	Helper runs as root; no entitlement needed
Screen lock	Rage Quit	Shells out to /System/Library/CoreServices/Menu Extras/User.menu/Contents/Resources/CGSession -suspend
Audio playback	Reaction + relax sounds	AVAudioPlayer, no entitlement
Login items / daemon install	Approve helper at boot	SMAppService (macOS 13+)
Custom Rage-Quit track	User picks their own song	NSOpenPanel + security-scoped bookmark

Not required: Accessibility, Input Monitoring, Screen Recording, Camera, Microphone.

The app bundle is not sandboxed. The Mac App Store is not a viable distribution path because raw HID access to the SPU device isn't granted to sandboxed apps.

Future paid-Developer-ID distribution

The source is ready for notarization. Swap two lines in Packaging/build.sh:

codesign --force --sign "Developer ID Application: Your Name (TEAMID)" \
    --options runtime \
    --entitlements App/FreeSlapMac.entitlements --deep "$APP_BUNDLE"

xcrun notarytool submit build/FreeSlapMac.dmg --apple-id … --team-id … --password … --wait
xcrun stapler staple build/FreeSlapMac.dmg

Roadmap (not in v1)

• Lid-open/close "creak" reactions (IOKit power-mgmt notifications)
• USB plug/unplug "moaner" (IOServiceAddMatchingNotification)
• Voice-pack manager with multiple bundled packs
• Sparkle auto-update
• Homebrew cask

Buy me a Koffee

https://ko-fi.com/amir0

Credits

• Detection approach & accelerometer reverse-engineering: taigrr/spank
• Inspiration & feature set: slapmac.com
• Swift tooling guidance: hmohamed01/swift-development