rcade is a fully documented R package with detailed articles on its systems and their application.
Some of my best writing is in the articles for the Snake Devlog and Rendering System, but I think all the articles are fun to read :)

The package has around 1,200 lines of code and 20,000 words of documentation.

devtools::install_github("gbkorr/rcade")

The package lets you play and develop games in vanilla R, played right on the console!
Check out the website to learn more about more about the package and browse the documentation.

Source Code: https://github.com/gbkorr/rcade