lux
lux(1)
is a basic command-line utility to query and modify display brightness.
Documentation regarding usage is contained within the lux(1)
manual page.
Installation
If you're on an arch-based Linux distribution, then you can install lux from the aur:
paru -S clux # The lastest stable release
paru -S clux-git # The most up-to-date release
Otherwise if you would like to build from source, simply run:
git clone git://git.thomasvoss.com/lux.git
cd lux
make
make install