SlapMacPro

Slap your MacBook and it screams back. Open-source, free, no license required.

Built by reverse-engineering SlapMac and studying taigrr/spank, then rewriting from scratch in Swift with extra features using private macOS APIs.

Quick Start

# 1. Clone the repo
git clone https://github.com/AbdullahFID/SlapMacPro.git
cd SlapMacPro

# 2. Build, install, and launch at login (one command)
make install

Not comfortable with git? Just click the green Code button on GitHub → Download ZIP, unzip it, open Terminal, cd into the unzipped folder, and run make install.

Pre-built Binary (no Xcode needed)

Download the latest release from the Releases page. Unzip it and run:

cd SlapMacPro-release
./install.sh

This copies the pre-built binary, sets up launch at login, and starts the app. No Xcode or Swift toolchain required.

That's it. A hand emoji (👋) appears in your menu bar. It starts automatically every time you log in. Slap your MacBook.

If you just want to run it without installing:

swift build -c release
codesign --force --sign - .build/release/SlapMacClone
.build/release/SlapMacClone

Setup

Requirements

• macOS 14.6+ (Sonoma or newer)
• Apple Silicon MacBook (M1 / M2 / M3 / M4 / M5)
• Xcode Command Line Tools (xcode-select --install)

Permissions

The app reads your MacBook's built-in accelerometer via IOKit HID. macOS may require:

1. Input Monitoring — Go to System Settings > Privacy & Security > Input Monitoring and add your Terminal app (Terminal.app, iTerm2, etc.)
2. If that doesn't work, try running with sudo once to bootstrap permissions

Sound Files

You need .mp3 or .wav sound files in ~/Desktop/slapmac/audio/. Name them with these prefixes:

Prefix	Voice Pack
sexy_	Sexy
punch_	Combo Hit
male_	Male
fart_	Fart
gentleman_	Gentleman
yamete_	Yamete
goat_	Goat
1_ through 9_	Combo announcer clips

Example: sexy_01.mp3, punch_05.mp3, goat_3.mp3

You can use any sounds you want — record your own, grab free sound effects, whatever. Just drop them in the folder with the right prefix and restart the app.

Using SlapMac's sound files: If you download SlapMac, you can copy their 130+ sound files from the app bundle for personal use WITHOUT PAYING:

mkdir -p ~/Desktop/slapmac/audio
cp /Applications/slapmac.app/Contents/Resources/*.mp3 ~/Desktop/slapmac/audio/
cp /Applications/slapmac.app/Contents/Resources/*.wav ~/Desktop/slapmac/audio/

Note: SlapMac's audio files are copyrighted by tonnoz. You may use them locally for personal use if you own the app, but do not redistribute them.

Install with Launch at Login

make install

This will:

• Build a release binary
• Copy it to ~/Desktop/slapmac/bin/SlapMacPro
• Create a LaunchAgent (~/Library/LaunchAgents/com.slapmacpro.plist) so it starts automatically at login
• Launch it immediately

No .app bundle needed — it uses a standard macOS LaunchAgent which works with any binary.

Managing Launch at Login

# Disable auto-start (keeps installed, just won't launch at login)
make disable

# Re-enable auto-start
make enable

# Manually stop the running app
launchctl unload ~/Library/LaunchAgents/com.slapmacpro.plist

# Manually start it
launchctl load ~/Library/LaunchAgents/com.slapmacpro.plist

Uninstall

make uninstall

Removes the binary, LaunchAgent, and stops the app completely.

Other Commands

# Build debug
swift build

# Build release
make build

# Run without installing (debug, with console output)
swift build && .build/debug/SlapMacClone 2>&1

# View live detection logs
tail -f /tmp/slapmacpro.log

Features

• 5-algorithm slap detection — High-Pass Filter, STA/LTA (3 timescales), CUSUM, Kurtosis, Peak/MAD. They vote. Democracy, but for physical abuse.
• 7 voice packs — Sexy, Combo Hit, Male, Fart, Gentleman, Yamete, Goat
• Dynamic volume — Logarithmic scaling: gentle taps whisper, hard slaps scream
• Escalation tracking — Keep slapping and sounds escalate with a 30s decay half-life
• Screen Shake — Captures your screen and shakes it on impact
• Brightness Flash — DisplayServices private API dims/flashes the actual hardware backlight
• Trackpad Haptic Feedback — Trackpad buzzes on impact
• Screen Flash — White overlay flash (AppKit)
• USB Moaner — Plug/unplug USB data devices and it reacts
• Intensity sliders — Per-effect intensity control from the menu bar
• Menu bar app — No dock icon, lives in your menu bar with full controls
• Launch at login — Via LaunchAgent, no .app bundle needed
• Combo system — Combo Hit pack has an announcer that calls out your combo tier

Menu Bar Controls

Click the 👋 in your menu bar to access:

 Enabled / Disabled
 Voice Pack          → Sexy, Combo Hit, Male, Fart, Gentleman, Yamete, Goat
 Sensitivity         → Extremely Sensitive ... Requires Significant Force
 Cooldown            → None, Fast, Medium, Slow, Very Slow
 Dynamic Volume      → on/off

 Effects
 Screen Flash        → on/off + intensity slider
 Screen Shake        → on/off + intensity slider
 Brightness Flash    → on/off + intensity slider
 Trackpad Haptic     → on/off + intensity slider
 USB Moaner          → on/off

 Volume              → master slider
 Reset Slap Count
 Quit

All settings persist automatically between launches.

Architecture

MenuBarExtra (SwiftUI)
  └─ SlapController
       ├─ AccelerometerReader   ← IOKit HID, AppleSPUHIDDevice, ~125Hz
       ├─ SlapDetector          ← 5 algorithms vote on impact
       │    ├─ HighPassFilter   ← strips gravity (1st order IIR)
       │    ├─ STALTADetector   ← seismology algorithm (3 timescales)
       │    ├─ CUSUMDetector    ← cumulative sum change detection
       │    ├─ KurtosisDetector ← 4th statistical moment spike detection
       │    └─ PeakMADDetector  ← median absolute deviation outlier detection
       ├─ AudioPlayer           ← AVFoundation, escalation tracking
       ├─ ScreenShaker          ← CGDisplayCreateImage + overlay shake
       ├─ BrightnessFlash       ← DisplayServices private API
       ├─ HapticFeedback        ← NSHapticFeedbackManager
       ├─ ScreenFlash           ← AppKit NSPanel overlay
       ├─ USBMonitor            ← IOKit notifications + polling
       └─ SettingsStore         ← UserDefaults persistence

How the Detection Works

Your MacBook has a Bosch BMI286 IMU (Inertial Measurement Unit) running at 1kHz through Apple's Sensor Processing Unit (AppleSPUHIDDevice). The raw reports are 22 bytes with 3-axis acceleration as int32 Q16 fixed-point values.

We decimate to ~125Hz, strip gravity with a high-pass filter, then run the magnitude through five concurrent detectors:

1. STA/LTA — Short-Term Average / Long-Term Average ratio at 3 timescales (fast/medium/slow). Classic earthquake detection algorithm borrowed from seismology.
2. CUSUM — Cumulative Sum detects sustained shifts in mean acceleration.
3. Kurtosis — Measures signal "peakedness". A sharp impact creates a heavy-tailed distribution with high excess kurtosis.
4. Peak/MAD — Median Absolute Deviation outlier detection. More robust than standard deviation against baseline contamination.

The detectors vote. When enough agree, it classifies the event:

Detectors	Amplitude	Classification
4+ agree	> 0.05g	Major Shock
3+ agree	> 0.02g	Medium Shock
Peak fires	> 0.005g	Micro Shock

Volume scales with impact force using a logarithmic curve: intensity = log(1 + t * 99) / log(100)

Private APIs Used

API	Framework	Purpose
_CGSDefaultConnection	CoreGraphics	Get WindowServer connection for screen capture
CGSSetWindowTransform	CoreGraphics	Window affine transforms (screen shake)
DisplayServicesGetBrightness	DisplayServices	Read hardware backlight level
DisplayServicesSetBrightness	DisplayServices	Set hardware backlight level

These are loaded via @_silgen_name and dlopen/dlsym. They work on all Apple Silicon Macs without SIP changes.

Troubleshooting

"No accelerometer device found"

• Make sure you're on an Apple Silicon MacBook (not an iMac/Mac Mini/Mac Pro — they don't have accelerometers)
• Grant Input Monitoring permission to your terminal app in System Settings > Privacy & Security > Input Monitoring
• Try restarting your terminal after granting permissions

No sound plays

• Check that sound files exist in ~/Desktop/slapmac/audio/
• Check that they have the correct prefix (sexy_, male_, etc.)
• Check your Mac's volume isn't muted

Screen shake doesn't work

• Screen shake captures and overlays your screen. If you have very high resolution or multiple displays it might be subtle — crank the intensity slider up in the menu bar

USB Moaner doesn't detect my device

• The device must enumerate as a USB data device in macOS. Charge-only cables or devices that don't present USB data won't trigger
• Check with system_profiler SPUSBDataType — if your device doesn't show there, SlapMacPro can't see it either

App doesn't start at login

• Run make install to set up the LaunchAgent
• Check with launchctl list | grep slapmacpro

Credits

• Inspired by SlapMac by tonnoz
• Accelerometer approach from taigrr/spank
• Detection algorithms based on seismological signal processing (STA/LTA, CUSUM, Kurtosis)

License

MIT