Erlang and unixODBC on Mac OS

I filed an issue about this here erlang_odbc not building correctly on OSX/darwin · Issue #94644 · NixOS/nixpkgs · GitHub and I’d like to fix this problem myself.

How would I start inspecting this issue? I presume I’d need a MacOS machine with the nixpkgs repository checked out and then DO_STUFF:tm:

So it would be awesome if anyone could give me a pointer to the correct docs, a guide or something like that to get started.