smack.nvim

Neovim plugin that detects when you physically hit your MacBook and undoes your changes. Hit it harder, undo more.

Uses the Apple Silicon accelerometer (Bosch BMI286 IMU) to detect impacts and classify them into three severity tiers. Includes a screen shake effect for maximum feedback.

Hit	g-force	Undos	Shake
Light tap	> 0.3g	1	subtle
Medium hit	> 1.0g	3	moderate
Hard smack	> 2.0g	5	violent

Requirements

• Apple Silicon MacBook (M2 or later)
• macOS
• Neovim 0.9+

Note: Does not work on M1, Intel Macs, Mac Studio, Mac Mini, iMac, or Mac Pro — they lack the MEMS accelerometer.

Installation

1. Install the smack daemon

One-liner that downloads the latest binary, installs it, and starts the LaunchDaemon:

curl -fsSL https://raw.githubusercontent.com/duncanlutz/smack.nvim/master/install.sh | bash

Manual install / build from source

Download prebuilt binary

# Download and extract the latest release
curl -L https://github.com/duncanlutz/smack.nvim/releases/latest/download/smack_v0.1.0_darwin_arm64.tar.gz | tar xz
sudo mv smack /usr/local/bin/

Build from source

cd smack
cargo build --release
sudo cp target/release/smack /usr/local/bin/

Start the daemon

smack requires root for IOKit HID access. Run it manually:

sudo smack

Or install as a Launch Daemon (starts automatically on boot):

sudo cp com.smack.plist /Library/LaunchDaemons/
sudo launchctl load /Library/LaunchDaemons/com.smack.plist

To uninstall:

sudo launchctl unload /Library/LaunchDaemons/com.smack.plist
sudo rm /Library/LaunchDaemons/com.smack.plist /usr/local/bin/smack

2. Install the plugin

lazy.nvim

{
  "duncanlutz/smack.nvim",
  config = function()
    require("smack").setup()
  end,
}

packer.nvim

use {
  "duncanlutz/smack.nvim",
  config = function()
    require("smack").setup()
  end,
}

vim-plug

Plug 'duncanlutz/smack.nvim'

-- in after/plugin/smack.lua or init.lua
require("smack").setup()

Usage

The plugin auto-connects to smack on startup. Then just hit your laptop.

Commands

Command	Description
:SmackStart	Connect to the smack daemon
:SmackStop	Disconnect
:SmackToggle	Toggle connection

Configuration

require("smack").setup({
  socket_path = "/tmp/smack.sock", -- smack daemon socket
  enabled = true,                  -- auto-connect on startup
  shake = true,                    -- screen shake effect
  undo_count = {                   -- undos per severity
    light = 1,
    medium = 3,
    hard = 5,
  },
  shake_intensity = {              -- shake amplitude per severity
    light = 1,
    medium = 3,
    hard = 5,
  },
})

Architecture

┌─────────────────┐     Unix socket      ┌─────────────────┐
│  smack (Rust)   │ ──────────────────▶   │  smack.nvim     │
│                 │   /tmp/smack.sock     │  (Lua)          │
│  IOKit HID      │                       │                 │
│  ▸ read accel   │   JSON events:        │  ▸ parse event  │
│  ▸ detect hits  │   {"severity":"hard", │  ▸ undo N times │
│  ▸ broadcast    │    "amplitude":2.34,  │  ▸ screen shake │
│                 │    "undos":5}         │  ▸ notify       │
└─────────────────┘                       └─────────────────┘
     (sudo)                              (multiple instances)

smack runs as root (required for accelerometer access), broadcasts hit events over a Unix socket. Any number of Neovim instances can connect simultaneously.

Credits

Accelerometer interface ported from olvvier/apple-silicon-accelerometer. Inspired by spank.

License

MIT