- The Well-Grounded Rubyist, 3rd Ed. - David A. Black & Joseph Leo III - 2019 - The best "understand Ruby deeply" book: objects, blocks, modules, and metaprogramming.
- Practical Object-Oriented Design, 2nd Ed. - Sandi Metz - 2018 - Uses Ruby to teach OOP clearly; one of the best object-oriented design books for any language.
- Programming Ruby 3.2, 5th Ed. - David Thomas, Chad Fowler, Andy Hunt - 2023 - The definitive Ruby reference; "the Pickaxe."
- Ruby on Rails Tutorial, 7th Ed. - Michael Hartl - 2022 - Learn Rails 7 through three apps; testing, Git, deployment, Hotwire, Turbo; free online.
- Agile Web Development with Rails 7.2 - Sam Ruby, Dave Thomas, David Heinemeier Hansson - 2024 - Build a store app with Rails; Hotwire, Stimulus, Turbo, testing, WebSockets.
- Programming Ruby 4, 6th Ed. - Noel Rappin, Dave Thomas - 2024 - The Pickaxe updated for Ruby 4; language, standard library, and ecosystem.
- Metaprogramming Ruby 2 - Paolo Perrotta - 2014 - Master Ruby's dynamic nature: blocks, classes, modules, and DSLs.
- The Ruby Way, 3rd Ed. - Hal Fulton & André Arko - 2015 - Solutions and idioms for common Ruby tasks; reference and cookbook.