Setting the color temp of the screen really only requires about 40 lines of C (80 or so all inclusive). sct is a crude utility which does roughly that. I’d say exactly that, but some of the calculations aren’t actually exact.
Windows Night Light Alternatives
Windows Night Light is described as 'To schedule Night Light so it turns on automatically, select Start > Settings > System > Display > Night light > Night light settings' and is a color temperature tool in the system & hardware category. There are more than 50 alternatives to Windows Night Light for a variety of platforms, including Windows, Mac, Linux, Android and Wayland apps. The best Windows Night Light alternative is f.lux, which is free. Other great apps like Windows Night Light are Redshift, Solace, LightBulb and Red Moon.
Alternatives list
Night Screen is created for those people who spend a lot of time at night working.
Limit your exposure to energy-efficient lighting before bed. In addition to the LED screens in your electronics, energy-efficient lighting emits a lot of blue light.


+1
- 50 Nocturne alternatives
Nocturne is simple app for switching a computer to night vision mode. It has a few tricks up its sleeve: color correction, window shadow toggling, and background removal.
Cost / License
- Free
- Open Source
Alerts
- Discontinued
Platforms
- Mac

Shady puts a shade over your screen to help soothe your tired or dazzled eyes. You can use it to reduce your Mac's brightness far below the usual minimum, without any risk of damage to your screen.
Cost / License
- Free
- Open Source
Platforms
- Mac

Cost / License
- Freemium
- Proprietary
Platforms
- Android
SunshinePal is your daily sunlight companion designed to help you track your exposure, set healthy goals, and reconnect with nature for better sleep and mood.
Cost / License
- Freemium
- Proprietary
Platforms
- iPhone
- Apple Watch


+5
A Python program that calculates ambient brightness and sets screen's correct backlight using a camera.

Stop burning your eyes! myPoint Shade is caring for your eyes' comfort.
If you work in a dark room or struggle with eye strain and headache, myPoint will tune up your displays - this way it will care for your health and comfort.
myPoint allows you to adjust the brightness o.


+2
Lumen - magic auto brightness based on screen contents. You control Lumen simply by using your brightness keys - it'll automatically learn your preferences.


Small GTK GUI application to set contrast, brightness and gamma for wayland compositors which support the wlr-gamma-control protocol extension. Basically this is the example from here: https://github.com/swaywm/wlroots/blob/master/examples/gamma-control.
Cost / License
- Free
- Open Source (MIT)
Platforms
- Linux
- Wayland

































