How to download and install f.lux on your Mac.If you're itching for a Night Shift-style option for your older Mac, you can download and customize f.lux right now! Here's how. It works with older Macs, and even Macs running older operating systems, like El Capitan and Yosemite. It's been a great tool for years on the Mac - and might just have been the inspiration for Night Shift. Unfortunately, it isn't available on older devices, including MacBooks older than early 2015.į.lux is an app that offers Night Shift-style brightness and hue adjustments depending on the time of day. With macOS 10.12.4, Apple added Night Shift, which warms the color of your screen after sunset and before sunrise.