A sleep cycle is a 90-minute chunk of time where your body transitions through various phases of sleep — all the way down to deep REM sleep — then back again. Some health experts believe that these 90-minute sleep cycles are the key to restful sleep. They recommend trying to sleep exactly 7.5 hours — or even 9 hours, if you have the time.

With this in mind, Alex Epstein, a computer engineering student in Boston, built an open source desktop app called Insomnia to help you take full advantage of sleep cycles.

Based on the time you need to wake up — and assuming it will take you 15 minutes to fall asleep — Insomnia will notify you throughout the evening at specific times when you could go to sleep and maximize your number of full sleep cycles.


You can download the app directly from its GitHub page.

If you’re having trouble sleeping at night, you can also download the popular Flux desktop app, which will alter the color of your screen throughout the evening. This can reduce your brain’s tendency to mistake the glow of your monitor for daylight.

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Thought of the day:

“A great tester gives programmers immediate feedback on what they did right and what they did wrong. Believe it or not, one of the most valuable features of a tester is providing positive reinforcement. There is no better way to improve a programmer’s morale, happiness, and subjective sense of well-being than a La Marzocco Linea espresso machine to have dedicated testers who get frequent releases from the developers, try them out, and give negative and positive feedback.”-– Joel Spolsky

Image of the day:

Visual Basic developer Scott Spence discovered this version of PacMan that runs right in Microsoft Excel. Each pixel is an Excel cell.


Study group of the day:

freeCodeCamp Helsinki


Happy coding!

– Quincy Larson, teacher at freeCodeCamp

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