slab #

A lid-closed ambient + reactive audio system for the MacBook, gated on Claude Code activity, with a completion chime that sleeps the Mac when the last thread finishes.

Close the lid while Claude has active work in flight (with sleep suppressed) and the laptop becomes a "sleeping slab": an ambient C-major-pentatonic bed loops through the speakers while a mic-listener picks up claps, snaps, shushes, kisses, hums, and close-up sings — responding in real time with short pentatonic pluck-arpeggios that mirror each sound's pitch contour. Close the lid with nothing active and it's silent. When Claude finishes a prompt, it beeps once per other in-flight prompt or subagent; when the last piece of work completes, the "all-done" chime plays — and if the lid is closed, the Mac sleeps right after.

Active work is tracked as marker files in two directories:

• $SLAB_HOME/state/active-prompts/<session_id> — created by the UserPromptSubmit hook, removed by Stop.
• $SLAB_HOME/state/active-subagents/<ts>-<pid>-<n> — created by the PreToolUse hook (filtered to the Task tool), removed (oldest-first) by SubagentStop.

The daemon treats the total file count as "active work". When the Stop hook runs with zero remaining markers and the lid is closed, ambient stops, the all-done chime plays, and the Mac sleeps.

What it does #

Event	Sound
Lid close (disablesleep=1)	display sleep. Ambient only if a prompt or subagent is in flight.
Prompt or subagent starts while lid closed	ascending C-arp + ambient loop starts
Mic transient while ambient is playing (> 2 kHz)	4-note pentatonic pluck arp, contour mirrors input
Lid open while ambient playing	descending ding + smooth descending arp stinger + ambient stops
Lid open with no ambient	silent
Subagent finishes (Task tool)	single ping
Claude Stop, other active work remaining	N ascending beeps (C6 D6 E6 G6 A6 C7 D7 E7)
Claude Stop, all work done, lid open	"all-done" chime
Claude Stop, all work done, lid closed	TTS "i'm tired" with cosine fade-out tail → pmset sleepnow
User submits new prompt	touches active-prompts marker, sets disablesleep=1

Install #

git clone git@github.com:whistlegraph/aesthetic-computer.git
cd aesthetic-computer/slab
./install.sh

The installer will:

1. Symlink scripts into ~/.local/bin/
2. Copy sound assets into ~/.local/share/slab/sounds/
3. Build a Python venv at ~/.local/share/slab/venv/ with numpy, sounddevice, and rumps
4. Install two launchd agents:
   • ~/Library/LaunchAgents/computer.slab.daemon.plist — the lid-ambient daemon
   • ~/Library/LaunchAgents/computer.slab.menubar.plist — a menu-bar status item + transparent full-screen HUD in the top-right corner of the screen
5. Merge hooks into ~/.claude/settings.json (Stop, SubagentStop, PreToolUse(Task), UserPromptSubmit, SessionStart)
6. Install a passwordless-sudo rule at /etc/sudoers.d/slab-pmset for pmset (prompts for password once)

Opt-outs: --no-hooks, --no-sudoers.

Usage #

claude-sleep awake     # disable all sleep (stay awake with lid closed)
claude-sleep auto      # restore normal sleep behavior
claude-sleep now       # sleep the Mac immediately
claude-sleep status    # show SleepDisabled state

Before using lid-closed ambient mode: claude-sleep awake. The first time the mic listener runs you'll get a macOS microphone permission prompt.

Uninstall #

./uninstall.sh           # unload agent, remove symlinks + hooks + sudoers
./uninstall.sh --purge   # also delete ~/.local/share/slab (sessions, logs, venv, sounds)

Layout #

slab/
├── bin/                                 # scripts (symlinked into ~/.local/bin/)
│   ├── lid-ambient.sh                   # launchd daemon, polls lid + active prompts
│   ├── lid-reactive.py                  # mic → pluck-arp synth + noise voice (Python)
│   ├── lid-ambient-synth.swift          # live AVAudioEngine ambient drone + capture (Swift)
│   ├── lid-return-generate.py           # generate lid-return.wav (smooth descending arp)
│   ├── slab-menubar.py                  # rumps menu bar status item (no Dock icon)
│   ├── claude-sleep                     # sleep-state toggle
│   ├── claude-stop.sh                   # Stop-hook entry (prompts + subagents aware)
│   ├── claude-prompt-log.sh             # UserPromptSubmit hook (touches active-prompts marker)
│   ├── claude-tool-pre.sh               # PreToolUse(Task) hook (touches active-subagents marker)
│   ├── claude-subagent-stop.sh          # SubagentStop hook (pops oldest subagent marker + ping)
│   ├── claude-ping-repeat.sh            # legacy 30s pings (no longer invoked)
│   ├── claude-sleep-schedule.sh         # legacy delayed auto-sleep (no longer invoked)
│   ├── slab-monitor.sh                  # resource sampler
│   └── slab-zone                        # location-zone manager
├── sounds/                              # WAV assets (lid chimes, pings, beeps)
├── launchd/
│   ├── computer.slab.daemon.plist.template
│   └── computer.slab.menubar.plist.template
├── sudoers.d/
│   └── slab-pmset.template
├── settings-fragment.json               # Claude Code hooks, merged on install
├── install.sh
└── uninstall.sh

Runtime state lives under ~/.local/share/slab/:

sessions/<stamp>-<zone>.wav    per-lid-close mix of Python listener output (noise + plucks)
sessions/ambient-<stamp>.wav   per-lid-close recording of the live Swift ambient drone
sessions/<stamp>-<zone>.jsonl  trigger events + location metadata
logs/lidalive.log              daemon transitions
logs/reactive.log              reactive listener triggers
logs/resources.jsonl           CPU/RSS samples every 15s
logs/claude-stop.log           Stop-hook activity
config/zones.json              geofenced zones + per-zone scale/dynamics
state/active-prompts/<id>      one file per Claude session with a prompt in flight
state/active-subagents/<id>    one file per in-flight Task-tool subagent
state/last-location.json       cached coords (if Location Services unreachable)
venv/                          Python venv for the reactive listener
sounds/                        installed sound assets (lid chimes, pings, beeps)

Zones (location-aware ambient) #

Each lid-close queries Core Location and picks the closest zone in ~/.local/share/slab/config/zones.json. The matching zone overrides the reactive listener's scale, pitch mapping (div_factor), and amp. Coords + zone name are written into the session JSONL and appended to the WAV filename.

brew install corelocationcli                 # one-time (install.sh can run it)
# grant Location Services permission once
slab-zone where                              # show current coords + zone
slab-zone add home 150                       # pin current spot as 'home', 150m radius
slab-zone add studio 60
slab-zone list                               # dump zones.json
slab-zone remove home

Available scales: major_pentatonic, minor_pentatonic, blues, dorian, phrygian, lydian, whole_tone, chromatic. Edit zones.json directly to tweak a zone's scale, div_factor, or arp_amp.

Tuning #

Most knobs live at the top of each script:

• Ambient — bin/lid-ambient-synth.swift: scale, note-gap range, duration/fade ranges, detuning, drone frequency, AU effects (reverb preset, delay time/feedback). Recompile via swiftc -O -o ~/.local/bin/lid-ambient-synth bin/lid-ambient-synth.swift (install.sh does this automatically).
• Reactive listener — bin/lid-reactive.py: HIGH_BAND, TRIGGER_RATIO, MIN_GAP, DIV_FACTOR, NOTE_DUR, PLUCK_TAIL, ARP_NOTES, ARP_AMP. Scales live in SCALE_INTERVALS.
• Lid-poll interval — bin/lid-ambient.sh: POLL (default 0.5s).
• Resource poll — bin/slab-monitor.sh: INTERVAL (default 15s).

Edits to files in slab/bin/ take effect immediately because the installed copies are symlinks back into the repo.

Requirements #

• macOS (Apple Silicon tested). Intel should work but the display-sleep-on-lid-close path depends on pmset displaysleepnow.
• Homebrew, Python 3.11+, jq, swiftc (Xcode Command Line Tools).
• Microphone permission for the reactive listener (prompted on first run).

Notes #

• pmset disablesleep 1 suppresses all sleep, including explicit pmset sleepnow — the sudoers rule lets the scheduler toggle it back off before suspending.
• The reactive listener writes 44.1 kHz mono int16 WAVs of only its own output (the pluck arps). The looping ambient afplay and the chimes aren't captured — that would need a loopback audio device like BlackHole.
• Session files accumulate forever by default. Purge periodically: rm ~/.local/share/slab/sessions/*.
• Apple Silicon MacBooks have no accelerometer, gyroscope, or accessible CPU temp via public APIs — so shake/gesture and temperature-modulation paths aren't implemented here yet.