ruby
books
- agile web development with rails 5.1
- eloquent ruby
- practical object-oriented design in ruby: an agile primer
- programming ruby 1.9 & 2.0: the pragmatic programmers' guide, 4th edition
- ruby on rails tutorial: learn web development with rails, 4th edition (note: this book is somewhat out of date compared to the live version on the author's website.)
- the well grounded rubyist, 3rd edition