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Clamshell

Revendiquer

Clamshell is a menu bar app for Apple Silicon MacBooks that keeps the Mac awake with the lid closed and no external display attached. It helps people run long tasks, coding agents, SSH sessions, and downloads without relying on admin-level sleep settings or extra hardware.

Clamshell preview

Keep an Apple Silicon MacBook awake with the lid closed

Clamshell is a menu bar app for Apple Silicon MacBooks that keeps the machine awake when the lid is shut. It is intended for cases where macOS would normally sleep, interrupting work in progress.

The app keeps the screen fully dark while the Mac continues running on battery or AC power. According to the source material, it does this without an external display, without sudo or admin access, and without a privileged helper.

Core features

Option-and-close arming

Hold Option while closing the lid to keep the Mac awake for that session, instead of triggering normal lid-close sleep.

No monitor required

Clamshell removes the usual macOS requirement for an attached external display, dock, or HDMI dummy plug.

Unprivileged implementation

The app is described as a normal menu bar app with no kernel extension, driver, privileged helper, or sudo requirement.

Built-in display sleeps fully

When armed, the built-in display goes dark while the computer continues to run, which preserves battery and hides the screen content.

Works through power changes

The app is described as surviving plug and unplug transitions and reapplying itself on each change.

Optional low-battery cutoff

A configurable low-battery switch can put the Mac to sleep below a chosen charge level so overnight work does not drain the battery flat.

Practical use cases

  • Overnight coding-agent runs

    Use Clamshell to keep Claude Code, Codex, or similar agents running after the lid is closed, instead of losing the session to sleep.

  • Long builds and downloads

    Leave test suites, builds, renders, or large downloads running while the screen stays off and the Mac continues processing.

  • Remote access on a closed laptop

    Keep SSH and screen sharing reachable while the machine stays awake and on the network.

  • Closed-lid work on battery

    Run lid-closed without staying plugged in, with the option to sleep automatically if battery charge falls too low.

  • Automated shell workflows

    Use the URL scheme or Shortcuts actions to arm and disarm Clamshell as part of a script or shortcut-driven workflow.

Pros and Cons

Pros

  • Keeps the Mac running with the lid closed while the screen stays off.
  • Does not require external display hardware or admin privileges.
  • Supports battery and AC power, including plug and unplug transitions.
  • Provides a low-battery safeguard for longer sessions.
  • Restores normal lid-close behavior on restart.

Cons

  • Only supported on Apple Silicon MacBooks running macOS 14 or later.
  • The Option-and-close gesture depends on a lid angle sensor, so it does not apply to every MacBook model.
  • Public pricing details were not available because the pricing URL returned a 404, so only the free trial and one-time purchase mentioned on the site can be confirmed.

FAQ

Which Macs and macOS versions are supported?

The source says Apple Silicon MacBooks on macOS 14 or later. The Option-and-close gesture requires a lid angle sensor, which the site identifies on MacBook Air M2 (2022) or later and 14-inch / 16-inch MacBook Pro (2021) or later.

Do I need an external display to use Clamshell?

No. Clamshell is presented as a way to run a MacBook lid-closed with no external display attached.

Will background work keep running when the lid closes?

Yes. The source says agents, terminal sessions, builds, downloads, SSH, and screen sharing keep running while the lid is closed and the Mac remains awake.

Does Clamshell need admin access?

No. The app is described as requiring no sudo, no kernel extension, no privileged helper, and no driver.

What happens after a restart?

Normal lid-close sleep returns after restart because the app’s change is not saved across restarts.

Quick Facts

Category
Developer Tool
Platform
Apple Silicon MacBooks
OS requirement
macOS 14 or later
Primary workflow
Keep the Mac awake with the lid closed
Deployment
Menu bar app
Source domain
clamshell.dev