# Show HN: Macsomnia – close your MacBook lid while keeping long jobs alive

> Source: <https://github.com/iamdadzilla/Macsomnia>
> Published: 2026-08-14 23:13:11+00:00

A macOS menu-bar app that stops your Mac from sleeping — including **clamshell
(lid closed) with no external display** — to keep long-running light jobs (AI
agents, builds, downloads) alive.

When active, a red strip spans the top of every screen and the menu-bar label shows a live countdown, so you can never miss that it's on. An auto-off timer turns it off after a duration you pick.

Requires macOS 13 (Ventura) or later.

Disabling clamshell sleep defeats a thermal-protective behavior. Macsomnia is
intended for **light** workloads. Running heavy, sustained CPU/GPU load with the
lid closed and no external cooling can cause dangerous heat buildup and may
damage your hardware. Use the auto-off timer. Macsomnia is provided as-is, with
no warranty; you use it at your own risk.

```
brew tap iamdadzilla/macsomnia
brew install --cask macsomnia
```

Recent Homebrew asks you to trust a third-party cask tap the first time. If the
install stops with an "untrusted tap" message, run the command it suggests
(`brew trust iamdadzilla/macsomnia`

) and re-run the install.

Upgrade later with `brew upgrade --cask macsomnia`

.

Grab the `Macsomnia-<version>.zip`

from the [latest release](https://github.com/iamdadzilla/Macsomnia/releases/latest),
unzip it, and move `Macsomnia.app`

to `/Applications`

. Builds are signed and
notarized, so they open without Gatekeeper warnings.

```
git clone https://github.com/iamdadzilla/Macsomnia.git
cd Macsomnia
./make-app.sh          # builds Macsomnia.app
```

Then move `Macsomnia.app`

to `/Applications`

. (Requires the Xcode command-line
tools.)

- Open Macsomnia. It shows a one-time danger/liability warning you must accept.
A
`zzz`

icon then appears in the menu bar. - The first time you enable it, Macsomnia registers a small privileged helper
(an
`SMAppService`

background daemon) that runs`pmset`

as root. macOS asks you to allow Macsomnia's background item in**System Settings → General → Login Items & Extensions**(under "Allow in the Background"). Approve it, then enable again — after that it works with no further prompts.

- Click the icon → choose a duration:
**30 min · 2 h · 4 h · 8 h · until I turn it off**. - While ON: a red strip appears across the top of every display, the label shows a live countdown, and the auto-off timer will disable it.
**Disable now** turns it off. Quitting the app also restores normal sleep.- If sleep gets disabled by anything else, Macsomnia detects it within ~5s, shows the red strip, and notifies you.

A signed helper daemon runs these as root, reached over XPC — only Macsomnia's own signed app is allowed to talk to it:

- Enable:
`pmset -b sleep 0 ; pmset -b disablesleep 1`

- Disable:
`pmset -b sleep 5 ; pmset -b disablesleep 0`

`disablesleep 1`

is what keeps the Mac awake with the lid closed — stronger than
the idle-sleep prevention that `caffeinate`

and similar tools use.

```
brew uninstall --cask macsomnia          # or delete Macsomnia.app
```

Upgrading from 1.0 (which used a sudoers rule instead of the helper)? Remove the now-unused rule:

```
sudo rm -f /etc/sudoers.d/macsomnia
```

MIT — see [LICENSE](/iamdadzilla/Macsomnia/blob/main/LICENSE).

[Promotion plan](/iamdadzilla/Macsomnia/blob/main/PROMOTION-PLAN.md)— launch and outreach notes