Gemified in 2.2-

The following libraries were made standard gems with Ruby 2.2 or earlier.

New Default Gems

Gem Description Resources
bigdecimal c Support for arbitrary-precision floating point decimal arithmetic RubyGems, GitHub, CRuby, RDoc
io-console c Patches IO for simple and portable access to the console RubyGems, GitHub, CRuby, RDoc
psych c Support for YAML (YAML Ain't Markup Language) RubyGems, GitHub, CRuby, RDoc
rdoc Ruby documentation generator RubyGems, GitHub, CRuby (1), CRuby (2), RDoc
rubygems RubyGems allows you to download, install, and use Ruby software packages on your system RubyGems, GitHub, CRuby (1), CRuby (2), RDoc

New Bundled Gems

Gem Description Resources
minitest Test/spec framework, comes with mocking and benchmark capabilities RubyGems, GitHub
power_assert Debug tool that displays intermediate results of a method chain RubyGems, GitHub
test-unit A xUnit family unit testing framework (compatibility layer for minitest) RubyGems, GitHub

More Standard Gems

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