I was wondering how I could try out the latest version of the mod by building it from source, but it did'nt get me far. I tried to run gradlew with the --build argument I think it was that. Many projects have a description on how to build the source code in the readme. But just posting how to do it here will help me too. Thanks in advance!

It's pretty much the same for 99% of the gradle projects out there.

First:
gradlew sDecW <-- This sets up a decompiled MC workspace "sDecW" is shorthand for "setupDecompWorkspace"

Special considerations:
My project needs 2 libraries in order to build correctly. Quark and ComputerCraft.
make a directory named "libs" in the project root and put the 2 jar files of those projects in it.
I'm using ComputerCraft-1.80pr1-build0.jar and Quark-r1.4-120.jar at the moment. Both of these are available on curseforge.

If you want to develop in eclipse then:
gradlew eclipse <-- This sets up a ready to import project file for eclipse IDE.

Finally to build to a jar file:
gradlew build <-- This builds the jar and puts it in build/libs in the main project folder

If you're developing in linux you'll need to prepend "./" to the gradle command to run it from the current directory. ie: ./gradlew build