Ruby

The name "Ruby" comes from the gemstone, chosen as a nod to the programming language Perl (pearl). The idea was to name a language intended to follow Perl after another gemstone. The playfulness embedded in the name reflects the designer's sensibility.

In the early 1990s, Yukihiro Matsumoto worked with multiple languages daily and felt a persistent frustration: why were they so difficult to write in? Perl had expressiveness he appreciated, but its syntax was overly complex. Python was well-structured but lacked joy. From those observations came the decision: "I'll build the language I want to use."

On February 24, 1993, Yukihiro Matsumoto began developing Ruby during breaks from his regular work. This date is commemorated as Ruby's birthday.

The development environment was MS-DOS on an NEC PC-9800 series machine. The languages that influenced Ruby's design span a wide range.

In December 1995, Ruby 0.95 was released on Usenet, followed shortly by Ruby 1.0. A community formed primarily around the Japanese mailing list (ruby-list).

The most widely cited principle in Ruby's design is the "Principle of Least Surprise." However, Yukihiro Matsumoto himself emphasizes that this means "least surprise for me (Matz)" — not a universal standard for all programmers. It is about the designer choosing behaviors that feel natural to himself as a programmer.

The other pillar is "Programmer Happiness." Taking the stance that "computers should be slaves to humans, not the other way around," Yukihiro Matsumoto placed optional type declarations, optional parentheses, and tolerance for multiple coding styles at the core of Ruby's design.

Ruby did not emerge in isolation. It was designed by studying the strengths of languages from the 1960s through the 1990s and synthesizing them into a unified whole.

From the mid-1990s through the 2000s, several dynamically typed scripting languages emerged around the same time as Ruby.

Ruby is widely used for web backend development. Development with Ruby on Rails is a common choice for startups and prototyping. Services such as GitHub, Shopify, Basecamp, and Cookpad were built with Rails.

mruby, led by Yukihiro Matsumoto, is used in embedded systems and IoT devices as a lightweight Ruby implementation for embedded Linux environments.

Ruby 3.x has made significant progress in performance and concurrency through JIT introduction, full adoption of YJIT, and the Ractor mechanism for parallel processing.

"Ruby exists only for Rails"

The widespread adoption of Ruby on Rails created a strong "Ruby = Rails" association, but Ruby is a general-purpose language that stands on its own without Rails. It is used for CLI tools, automation scripts, embedded systems (mruby), and designing domain-specific languages (DSLs), among other purposes.

"Least Surprise means it matches everyone's intuition"

As Yukihiro Matsumoto himself has explained, "Least Surprise" is a principle based on the designer's own intuition. Programmers accustomed to other languages may find some Ruby behaviors counterintuitive. It is not a design that avoids surprise for every programmer.

"Ruby is slow"

The reputation of "Ruby = slow" took hold based on the Ruby 1.8 era, before YARV was introduced. Since Ruby 1.9's adoption of YARV, and the full integration of YJIT in Ruby 3.x (with reported speed improvements of 1.5× to 3× over MRI), performance has improved substantially.