Verdict: pick Clamshell for Mac to keep a MacBook awake with the lid closed. It runs on macOS 14 or later, while Sleepless requires macOS 26. It needs no sudoers rule, admin password or helper, and never sets the system-wide SleepDisabled flag that Sleepless switches on. It is notarized by Apple, and its thermal protection is always on.
Clamshell for Mac keeps a MacBook awake with the lid closed, on power or battery, without touching pmset. No sudo, no monitor. Free for 7 days, then $9.99 once.
Download free trialApple Silicon, macOS 14+. Notarized by Apple. 3.6 MB. Or buy now, $9.99
Sleepless is a small, free menu bar app by Adam Boudjemaa that keeps a MacBook awake with the lid closed, on battery, with no external display. It is deliberately minimal: one switch, an auto-off timer and a battery floor, in a single AppKit source file. Clamshell for Mac is also focused on the closed lid, but it reaches it through a different door, one that needs no admin step and works on far more Macs.
Short version: Clamshell runs on macOS 14, 15 and 26, needs no sudo rule, is notarized and carries an always-on thermal cutoff. Sleepless needs macOS 26 and an admin step, and is not notarized.
Side-by-side comparison
Sleepless cells come from its GitHub README, source and releases, checked October 5, 2026. "Not stated" means we could not find it there; it does not mean the feature is missing.
| Clamshell Recommended | Sleepless | |
|---|---|---|
| Admin rights | None. No sudo, admin password, kernel extension, driver or privileged helper. | Once: the installer adds a sudoers rule for exactly pmset -a disablesleep 0 and 1. No daemon or kernel extension. |
| How lid-closed works | Unprivileged IOKit clamshell sleep-state control plus an idle-sleep assertion while armed. Never changes SleepDisabled. | Toggles pmset disablesleep, the kernel's SleepDisabled flag, and reads it back. |
| Platform | Apple Silicon MacBooks, macOS 14 or later. | macOS 26 or later (Info.plist), Apple Silicon build. |
| Signing | Developer ID signed and notarized by Apple. | Ad-hoc signed, not notarized: approve with Open Anyway, or build from source. SHA-256 checksums and build attestation. |
| Thermal safeguard | Always on. Serious or critical thermal pressure disarms toward normal lid sleep and blocks arming until cooled. | Not stated. Its FAQ says heavy sustained load with the lid shut reduces airflow, so use judgement. |
| When it ends | Restores normal lid sleep on disarm or quit, retrying and warning if macOS refuses. Never kept across a restart. | Switch off, timer, battery floor or Low Power Mode. A reboot resets the setting. |
| Lid closed, no display | Yes, on power or battery. | Yes, on battery too. |
| Price | 7-day free trial, then $9.99 once for 1 Mac or $19.99 for 3 Macs. 14-day money-back guarantee. | Free. |
| Distribution | clamshell.dev and Setapp. Version 1.4.21. | GitHub releases and a Homebrew tap (aboudjem/tap/sleepless). Latest release 1.2.7, June 3, 2026. |
| Battery safeguard | Optional low-battery disarm at a level you choose, off by default. | On by default: auto-off at a floor of 5 to 50%, default 15%. Also steps aside in Low Power Mode on battery. |
| Timer | No timer. Sessions end on disarm, quit, lid open after a one-close arm, or a safety cutoff. | Auto-off after 1 h or 2 h, with a live countdown. |
| Agent awareness | None. Arm from scripts with clamshell://arm and clamshell://disarm, or Shortcuts actions. | None stated. |
| Source code | Closed source. | Open source, MIT. One AppKit file. |
How Clamshell keeps the lid closed, and how Sleepless does
Closing the lid triggers its own sleep path, separate from idle sleep. caffeinate and apps built on it only block idle sleep, which is why they fail with the lid shut (here is why).
Clamshell uses an IOKit lid control that macOS lets an ordinary app call, plus an idle-sleep assertion, only while armed. Disarm or quit and it puts normal lid sleep back, and nothing carries over a restart. There is no password, no sudo rule and no system-wide flag.
Sleepless's README takes the classic workaround: sudo pmset -a disablesleep 1, which tells the kernel to ignore sleep requests entirely. A menu bar app cannot type your password, so its installer adds a sudoers rule that allows exactly two commands, the on and off switch, with no wildcards, and its uninstaller removes the rule. It is still a system-wide setting: while it is on, the Mac stays awake whether the lid is open or closed, until the switch, the timer, the battery floor, Low Power Mode or a reboot turns it off. Our pmset disablesleep guide explains what that setting does.
Safety nets: a thermal cutoff that is always on
Clamshell's thermal safety cannot be switched off: at serious or critical macOS thermal pressure it disarms toward normal lid sleep and blocks arming until the Mac cools. That matters most with the lid shut, where airflow is lower. Sleepless does not state a temperature cutoff; its FAQ asks you to use judgement under heavy load. Its safety nets are a battery floor, on by default at 15%, Low Power Mode on battery and a 1 or 2 hour timer. Clamshell's low-battery disarm is optional and off by default.
Why Clamshell is the better pick
- It runs on your macOS. Sleepless's Info.plist sets macOS 26 as the minimum. Clamshell runs on macOS 14 or later, so Sonoma and Sequoia Macs are covered too.
- No sudoers rule, no admin step. Sleepless needs an administrator once to add a sudoers rule, which stays in place until its uninstaller removes it. Clamshell needs no password at all, which matters on managed work Macs.
- No global sleep switch. While
pmset disablesleepis on, the whole Mac ignores sleep, lid open or closed. Clamshell overrides only lid sleep, only while armed, and restores it on disarm or quit. - Notarized by Apple. Clamshell is Developer ID signed and notarized, so it opens normally. Sleepless is ad-hoc signed, so macOS makes you approve it with Open Anyway.
- Thermal cutoff and a dark, locked return. Serious thermal pressure disarms Clamshell automatically. The built-in display stays black while closed, agents can still use the screen, and the display stays dark on reopen until the Mac is locked.
On macOS 14 or 15, or no admin rights? Clamshell is free for 7 days, then $9.99 once for one Mac.
Download free trialApple Silicon, macOS 14+. Notarized by Apple. 3.6 MB. Or buy now, $9.99
Other options compared: Keepresso (agent-aware, GPL) and Adrafinil (agent hooks, root helper). Paid: Hold My Lid, Helmlet and LidRun.
Frequently asked questions
Do I need sudo or an admin password to keep a MacBook awake with the lid closed?
Not with Clamshell for Mac. It uses an unprivileged IOKit control, so there is no sudo, admin password or privileged helper. Sleepless needs sudo once: its installer adds a sudoers rule that lets your user run exactly two commands without a password, pmset -a disablesleep 1 and pmset -a disablesleep 0.
Does Clamshell leave anything behind?
No. Clamshell adds no sudoers rule and never changes the system-wide SleepDisabled setting. Its lid override exists only while armed, normal lid sleep returns when you disarm or quit, and nothing is saved across a restart.
Is there a free trial?
Yes. Clamshell is free for 7 days with no card, then $9.99 once for one Mac or $19.99 for up to 3 Macs, with a 14-day money-back guarantee. Sleepless is free and open source under the MIT license.
Which macOS versions does Sleepless support?
Its Info.plist sets macOS 26 as the minimum and its build targets Apple Silicon. Clamshell runs on Apple Silicon MacBooks with macOS 14 or later.
What is the difference between Sleepless and Clamshell?
Sleepless is a free, MIT-licensed menu bar switch that turns on pmset disablesleep through a scoped sudoers rule, with an auto-off timer and a battery floor. Clamshell for Mac keeps an Apple Silicon MacBook awake with the lid closed while armed, using an unprivileged system control with no sudo rule, admin password or helper, and an always-on thermal cutoff.
Is there a Sleepless alternative that does not use pmset disablesleep?
Clamshell for Mac. It overrides lid sleep with an unprivileged IOKit control while armed and never changes the system-wide SleepDisabled setting. It costs $9.99 once after a 7-day free trial.
If you are on macOS 26, have admin rights and want a free, MIT-licensed switch with a timer, Sleepless covers that.
Ready to close the lid? Clamshell keeps your MacBook awake on macOS 14 or later, with no sudo. Free for 7 days, then $9.99 once.
Download free trialApple Silicon, macOS 14+. Notarized by Apple. 3.6 MB. Or buy now, $9.99
Related guides
- Best apps to keep a Mac awake
- What sudo pmset disablesleep 1 does and how to undo it
- Clamshell vs Keepresso
- Clamshell vs Helmlet
- Clamshell vs Adrafinil
- Clamshell vs Amphetamine vs pmset
Sources checked October 5, 2026: Sleepless's GitHub README, Info.plist, source and 1.2.7 release. Clamshell details come from its own documentation and changelog. Clamshell is the publisher of this comparison. Product names belong to their respective owners.