preface
The first edition of The Well-Grounded Rubyist was published in January 2009. The first decade of the 21st century drew to a close with incredible promise for a wildly popular language and the enthusiastic community that loved it.
Today, Ruby is solidly in the mainstream of serious, mature programming languages. Several companies built with Ruby have achieved legacy status, building and maintaining Ruby applications for many years. These companies have ushered in a new era for Rubyists who manage massive infrastructures undergirded by Ruby. Plenty of Rubyists remain at the cutting edge of technology and business, where Ruby remains a ready choice for entrepreneurs and startup founders.
The language of Ruby has matured in recent years. This book targets version 4.0. This major version of Ruby was released with little to no backwards-breaking changes, signaling the stability and trustworthiness of a language positioned for ambitious endeavors in the decades to come. The Well-Grounded Rubyist remains the most popular text for learning Ruby. Much of the teaching in the book is done by example, giving you countless opportunities to follow along with your own code and build on the foundations provided in the text. Earlier editions established this approach, and this fourth edition expands on it, providing more sample code and exercises than ever before.