The rubyzip module provides ways to read from and create zip files.

Diffy provides a convenient way to generate a diff from two strings or files.

Backports enables more compatibility across Ruby versions by providing backports of some features.

ExecJS lets you run JavaScript code from Ruby. It automatically picks a runtime to evaluate your JavaScript program, then returns the result to you as a Ruby object.

This package provides a Language Server Protocol (LSP) development kit for Ruby.

The Wapiti-Ruby gem provides a wicked fast linear-chain CRF API for sequence segmentation and labelling. It is based on the codebase of Wapiti.

Rack::Test is a small, simple testing API for Rack applications. It can be used on its own or as a reusable starting point for Web frameworks and testing libraries to build on.

Ruby C bindings to the Yajl JSON stream-based parser library. The API is compatible with the JSON gem, so yajl-ruby can act as a drop in replacement.

A modified copy of yajl is used, and included in the package.

Oedipus Lex is a lexer generator in the same family as Rexical and Rex. It is based primarily on generating code much like you would a hand-written lexer. It uses StrScanner within a multi-level case statement. As such, Oedipus matches on the first match, not the longest.

This package can speed up Test::Unit, RSpec, Cucumber, and Spinach tests by running them concurrently across multiple CPU cores.

Octokit wraps the GitHub API in a flat API client that follows Ruby conventions and requires little knowledge of REST.

This package provides a fake file system for use in test suites. It avoids the need for manually creating temporary directories, or dealing with platform intricacies in File and FileUtils.

This package adds color through ANSI escape codes to Bacon test output.

Middleware is a generalized implementation of a middleware abstraction for Ruby.

The ruby_parser (RP) package provides a Ruby parser written in pure Ruby. It outputs S-expressions which can be manipulated and converted back to Ruby via the ruby2ruby library.

This package provides the Minitest::Retry class, which extends Minitest to allow retrying tests when they fail.

YARD is a documentation generation tool for the Ruby programming language. It enables the user to generate consistent, usable documentation that can be exported to a number of formats very easily, and also supports extending for custom Ruby constructs such as custom class level definitions.

Sass is a CSS extension language. It extends CSS with features that don't exist yet like variables, nesting, mixins and inheritance.

Erubis is a fast implementation of embedded Ruby (eRuby) with several features such as multi-language support, auto escaping, auto trimming spaces around <% %>, a changeable embedded pattern, and Ruby on Rails support.

RGL is a framework for graph data structures and algorithms. The design of the library is much influenced by the Boost Graph Library (BGL) which is written in C++.

ValueSemantics generates modules that provide conventional value semantics for a given set of attributes. The behaviour is similar to an immutable Struct class, plus extensible, lightweight validation and coercion.

Inspired by Electric XML library for Java, REXML aims to be easy-to-use API, small and fast. It supports both tree and stream document parsing.

PandocRuby is a wrapper for Pandoc, a Haskell library with command line tools for converting one markup format to another. Pandoc can convert documents from a variety of formats including markdown, reStructuredText, textile, HTML, DocBook, LaTeX, and MediaWiki markup to a variety of other formats, including markdown, reStructuredText, HTML, LaTeX, ConTeXt, PDF, RTF, DocBook XML, OpenDocument XML, ODT, GNU Texinfo, MediaWiki markup, groff man pages, HTML slide shows, EPUB, Microsoft Word docx, and more.

ProgressBar is a simple library for displaying progress bars. The maximum value is configurable, and additional information can be displayed like the percentage completion, estimated time remaining, elapsed time and rate.