filmic v4 on the way

hello, I’d like to try V4 and compile it but I don’t know how to tweak my simple command sequence, can anyone show what’s needed please? I don’t know what to check out. This is how I would normally compile dt (Ubuntu 18.04) -

mkdir -p ~/DT-filmicV4-10May20
cd ~/DT-filmicV4-10May20
git clone https://github.com/darktable-org/darktable.git ~/DT-filmicV4-10May20/darktable-code
cd ~/DT-filmicV4-10May20/darktable-code
git checkout release-3.0.1
git submodule init
git submodule update
./build.sh AND SO ON…

Please be very specific! I have little understanding of Git…
Cheers