The most important code would be that which generated the .qasm file. That's not included in the repo, just the "compiled" result and a little program to run it. The code generator will look like a conventional C++ program that turns geometry operations (like line drawing) into subroutines which are written out to the .qasm file. There's no point to commit generated code to the repo.
The .qasm file can be found in the downloads/releases section.
The .qasm file can be found in the downloads/releases section.