As operation systems and build environments change more often and totally independent from Hydrogen, all build instructions can be found in our (more dynamic) Github Wiki:
These instructions may not be cutting-edge or might even fail on your particular system and setup. That is most likely because the development team uses and has access to just a small subset of systems.
The AppVeyor build pipelines used to create the Hydrogen releases might get you back on track. But you can always use the issues or discussions on Github or our mailing list to ask questions.