The repository[0] for J is just as unreadable (albeit with slightly more white space). I don’t know how a project is managed like this. Even the file names look obfuscated.
I think this is the main J repo [0]. (Though I’m not sure if it’s any more readable.) Possibly interesting that Tavmem is the maintainer of Kona (open source K3/4). I guess he’s comfortable with all APL/J/K languages.