This is RealistikOsu pp system, a modified version of oppai-ng with relax in mind.
To build oppai for cmd line usage, use ./build.
To build oppai as a library, use ./libbuild
More documentation is available on the original oppai repo.
Note we are not looking for miniscule changes to the pp system, if any at all. If you want to contribute that is fine however it should be well thought out, explained and be of use.