diff --git a/books/free-programming-books-langs.md b/books/free-programming-books-langs.md
index 37d94f032ed7b80253cd55a35c06f0fe2feb7ef6..d230df166542e1f996744431aa053c411ecda4f2 100644
--- a/books/free-programming-books-langs.md
+++ b/books/free-programming-books-langs.md
@@ -1975,6 +1975,7 @@ That section got so big, we decided to split it into its own file, the [BY SUBJE
 * [Just Enough Ruby to Get By](http://jasonkim.ca/projects/just_enough_ruby_to_get_by/)
 * [Learn Ruby First](https://essenceofchaos.gitbooks.io/learn-ruby-first/content/) - Frederick John
 * [Learn to Program](http://pine.fm/LearnToProgram/) - Chris Pine
+* [Mastering Roda](https://fiachetti.gitlab.io/mastering-roda) - Federico Iachetti, Avdi Grimm and Jeremy Evans
 * [Mr. Neighborly's Humble Little Ruby Book](https://web.archive.org/web/20180321101922/http://www.humblelittlerubybook.com/book/html/index.html)
 * [Object Oriented Programming with Ruby](https://launchschool.com/books/oo_ruby) - Launch School
 * [Practicing Ruby](https://github.com/elm-city-craftworks/practicing-ruby-manuscripts)