KeepingYouAwake is a small menu bar utility for macOS Yosemite (Version 10.10) and newer that can prevent your Mac from entering sleep mode for a predefined duration or as long as it is activated.
Download the latest version here.
or install it via cask: brew cask install keepingyouawake.
Caffeine from Lighthead Software is a great utility and I used it for many years, but it hasn't been updated in a while. Its icons are not Retina-compatible and do not look nice in the dark themed menu bar.
This utility is just a small wrapper around Apple's caffeinate command line utilty. Any modern Mac ships this tool by default. You can read the manpage here.
Just to make it clear: this utility shouldn't harm your Mac because it is using an official command line tool from Apple, BUT I cannot guarantee anything, so use this tool AT YOUR OWN RISK.
Do you want to improve the app or add any useful features? Please go ahead and create pull requests. I'm thankful for any help.
KeepingYouAwake uses Carthage as dependency manager. You can install Carthage with Homebrew. Type brew update && brew install carthage and call carthage bootstrap in the KeepingYouAwake source code folder to download and build all dependencies.
Everything in this project is licensed under the MIT license. I even included the Sketch files for all image assets in this project.