The biggest red flag for me is the author hiding their name. If you wrote quality book about a programming language you are not hiding your identity from the world.
The repository also has a misconfigured .gitignore file which allowed them to check in some built executables into the repository.
This is something that I wouldn't judge beginners for, but someone claiming to be an expert writing a book on the topic should know how to configure a .gitignore for their particular language of expertise.
This is something that I wouldn't judge beginners for, but someone claiming to be an expert writing a book on the topic should know how to configure a .gitignore for their particular language of expertise.