Capsomnia
Caps Lock keeps your Mac awake, even with the lid closed
230 followers
Caps Lock keeps your Mac awake, even with the lid closed
230 followers
Capsomnia turns Caps Lock into a physical switch that keeps your MacBook awake. Keep Claude Code, Codex, other AI agents, SSH sessions, builds, downloads, and more running after you close the lid. If Caps Lock is already assigned, choose another shortcut. The Caps Lock light still shows whether Capsomnia is active. The app is free and open source, signed and notarized. No accounts or telemetry. We’ve already seen strong interest in Japan: 2.3M+ views and 6,000+ downloads.
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Hey Product Hunt! 👋 I’m Taketo, the maker of Capsomnia.
I built Capsomnia around a tiny but frustrating MacBook problem: sometimes you want to close the lid without interrupting a local task, an AI coding agent, SSH session, build, download, or long-running script.
Capsomnia turns Caps Lock into a physical keep-awake switch because the key already has a built-in status light. If you already use Caps Lock for something else, you can choose a different shortcut, while the Caps Lock indicator still shows whether keep-awake mode is active.
When keep-awake mode is on, Capsomnia disables system sleep so your work can continue with the lid closed. Turn it off to restore normal sleep. The app is free, open source, signed, and notarized for Apple silicon Macs running macOS 14+.
There are no accounts, network requests, or telemetry. Since sleep is disabled while the mode is on, please keep airflow, power, and battery use in mind.
We’ve already seen strong interest in Japan: 2.3M+ views and 6,000+ downloads.
What would you run on your Mac with the lid closed?
@thys_beesman
Great question. With the lid closed, Capsomnia turns off the display, so battery consumption is significantly reduced compared with keeping the screen on.
That said, Capsomnia doesn’t currently have a dedicated low-battery safety cutoff or warning, so we recommend plugging in the Mac for overnight runs. Battery safety features are on our development roadmap.
the thermal question already came up and the honest "left to macOS" answer is a bit concerning given the use case. specifically curious about fanless machines - on a MacBook Air with no active cooling, would you actually advise against closing the lid for a long Claude Code or build run, versus a MacBook Pro that can at least move air internally? feels like the risk profile is pretty different between the two and worth calling out explicitly until the thermal-aware roadmap item ships
@galdayan
That’s a fair concern, and I agree the Air/Pro distinction should be called out explicitly. Capsomnia only prevents sleep—it doesn’t monitor temperature or change macOS’s thermal management.
For sustained, unattended CPU-heavy work, we’d be conservative with a fanless MacBook Air and recommend leaving the lid open, especially on battery or in a warm environment. A MacBook Pro with active cooling has more thermal headroom, but it can still throttle under sustained load, so it’s not a blanket guarantee either.
Until thermal-aware controls are available, the safest setup is to keep the Mac plugged in, on a hard surface with good airflow, and not treat Capsomnia as a thermal safeguard. We’re looking into thermal-, power-, and time-aware controls for the roadmap. Thanks for pushing us to clarify this.
@fuji_mak that's a genuinely useful distinction, honestly more caveat than I expected from a maker on their own launch thread, respect for not overselling it. "keep it plugged in on a hard surface" as the safe default makes sense in the meantime. will keep an eye out for the thermal-aware controls, that'd make this a much easier recommend for the fanless-Air crowd specifically.
The indicator light as a status signal is a clever use of hardware that already exists — way cleaner than a menu bar icon you might miss. Quick workflow question: when keep-awake mode is on and the lid is closed, does the app have any throttle or safety cutoff if the battery drops below a certain percentage, or is it fully manual? Just want to know if I should babysit it or if it handles the I forgot it was running case.
@leo404
Thanks! Right now, it’s fully manual, so there isn’t a low-battery cutoff yet. That said, an automatic safety cutoff based on battery level is already on the development roadmap—it should make the “I forgot it was running” case much safer.
Roadmap item noted — that is the real unlock for overnight Claude Code runs. A system notification at the threshold would be the cherry on top so it can actually alert you if you are not at the desk. Will check back for the update.
@leo404
Absolutely
we’ll share updates here and on X. Follow Capsomnia on Product Hunt and stay tuned for the release! Thanks again for the thoughtful suggestion.
clever repurposing of caps lock, but I'd worry about thermal buildup with the lid closed and vents blocked for a long build or training run. have you tested how hot these get compared to running with the lid open, and is there any thermal throttling safeguard built in or is that left entirely up to macOS?
@omri_ben_shoham1
That’s a really good point. we hadn’t considered thermal controls deeply enough. Capsomnia doesn’t currently add any extra thermal safeguard. Thermal management is left to macOS and the Mac’s built-in hardware protections.
Time-based keep awake controls are already on our roadmap, and we’ll also look into thermal-aware behavior. Thanks for flagging this!
Using the Caps Lock light as the status indicator is genuinely clever hardware reuse, no menu bar clutter needed. Also nice that it is signed, notarized and makes zero network requests. Any plans for the battery safety cutoff to kick in automatically when running on battery below a certain percentage?
@adamkamaneh
Yes, battery-aware controls are something we’re considering for the next update—including behavior based on whether the Mac is plugged in, as well as time-based limits. A percentage-based cutoff is a natural part of that direction too. Thanks for the thoughtful suggestion!
Ha, I love little utilities like this that do one thing well. My laptop going to sleep mid download has ruined more evenings than I want to admit. Congrats on the traction in Japan by the way, 2.3 million views before even launching here is wild. Does it play nicely with clamshell mode when an external display is connected?
@doganakbulut
Thanks so much! Yes—when an external display is connected and the Mac is in clamshell mode, Capsomnia leaves the Mac’s normal clamshell behavior unchanged. It should work just like a regular Mac setup.