Ruby is back-end code, this article is for front-end developers. That being said, you can do a large chunk of the back-end without needing any front-end code.

Ruby is back-end code, this article is for front-end developers. That being said, you can do a large chunk of the back-end without needing any front-end code. When it does come time to writing the front-end, you should focus on only front-end. Once it's done, you can merge the two. A possible exception to the rule would be full JS web applications.