Lunar.fyi - Control monitor brightness, adapt using the ambient light sensor, adjust volume, switch inputs and turn off displays without fiddling with clunky buttons.

Kumux - Kumux is a smart circadian color scheme designed for software like code editors.

DisplayBuddy - Control the real brightness of your monitors directly from your Mac - no need to touch the buttons on your Monitor.

ModernFlyouts - An open source, modern, and Fluent Design-based replacement for the old Metro-themed flyouts present in Windows 10.

BetterDummy - BetterDummy creates a virtual display which you can utilize as a mirror main for your display on the Mac.

Nocturne - Nocturne is simple app for switching a computer to night vision mode.