How to build this thing?

I would like to customize and help to this project, in particular adding more social options, but I can't find out how.

I've downloaded the zip file from here: https://www.ctan.org/tex-archive/macros/latex/contrib/moderncv and I've tried to run make inside examples/ dir but it stops saying:
make: *** No rule to make target 'moderncv.cls', needed by 'template_classic_green-right.pdf'. Stop.

If I copy all the moderncv files (.sty, .cls and so on) into examples and run make again it says:
 make: *** No rule to make target 'template_classic_green.diff', needed by 'template_classic_green-right.pdf'. Stop.

I can't figure out how to make example.tex using moderncv source code and the README file says nothing about this :S

Thank you for your awesome work anyway.