- The Ruby Programming Language, Yukihiro Matsumoto
- Practical Object Oriented Design in Ruby, Sandi Metz
- Design Patterns in Ruby, Russ Olsen
- Test-Driven Development: By Example Kent Beck
- Growing OO Software, guided by tests, Steve Freeman & Nat Pryce
- Clean Code, Robert C Martin
- Eloquent Ruby, Russ Olsen
- Exceptional Ruby, Avdi Grimm
- Metaprogramming Ruby, Paolo Perrotta
- Refactoring (ruby edition), Jay Fields, Shane Harvie, Martin Fowler & Kent Beck
- Seven Languages in Seven Weeks, Bruce Tate
- The Well Grounded Rubyist, David A Black
- Exception Ruby - Avdi Grimm
- Writing Solid Ruby Code - Jim Weirich
- The UNIX Chainsaw - Gary Bernhardt
- Confident Code - Avdi Grimm
- Why Ruby - DHH
- Zomg Why is this code so slow - Aaron Patterson
- SOLID Ruby - Jim Weirich
- exercism.io - Practice examples, and have them code reviewed by the community
- CodingDojo Kata list - kata to attempt
- The PragProg kata list - more kata.
- The Art of UNIX Programming, Eric Raymond