Citrus is a parsing library for Ruby that combines the expressiveness of the language with the parsing expressions.

Timers offers a collections of one-shot and periodic timers, intended for use with event loops such as async.

TTFunk is a TrueType font parser written in pure Ruby. It is used as part of the Prawn PDF generator.

Docile is a Ruby library that provides an interface for creating embedded domain specific languages (EDSLs) that manipulate existing Ruby classes.

This library uses the output of the ps command to create a process tree data structure for the current host.

This package provides a Ruby wrapper for the OAuth 2.0 protocol built with a similar style to the original OAuth spec.

Loofah is a general library for manipulating and transforming HTML/XML documents and fragments. It's built on top of Nokogiri and libxml2.

This package provides a simple block-driven assertion library for both testing and for production code that attempts to make test definitions more readable.

Rugged is a library for accessing libgit2 in Ruby. It gives you the speed and portability of libgit2 with the beauty of the Ruby language.

Fuubar is an RSpec formatter that uses a progress bar instead of a string of letters and dots as feedback. It also stops on the first test failure.

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 Ruby FFI bindings to the Networking and Cryptography (NaCl) library, also known as libsodium. This provides a high-level toolkit for building cryptographic systems and protocols.

Minima is a one-size-fits-all Jekyll theme for writers. It's Jekyll's default (and first) theme. It's what you get when you run jekyll new.

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.

Sequel provides thread safety, connection pooling and a concise DSL for constructing SQL queries and table schemas. It includes a comprehensive ORM layer for mapping records to Ruby objects and handling associated records.

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.

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.

This library allows reading and writing RPM packages. It is used by the fpm tool. It is written in pure Ruby because librpm is not available on all systems and requires many dependencies.

Spring is a Ruby on Rails application preloader. It speeds up development by keeping your application running in the background so the application does need to boot it every time you run a test, rake task or migration.

The x25519 gem is an efficient public key cryptography library for Ruby providing key exchange/agreement via the X25519 (as known as Curve25519) Elliptic Curve Diffie-Hellman function as described in RFC 7748.

Patron is a Ruby HTTP client library based on libcurl. It does not try to expose the full power (read complexity) of libcurl but instead tries to provide a sane API while taking advantage of libcurl under the hood.

This package provides a RBTree is a sorted associative collection that is implemented with a Red-Black Tree. It maps keys to values like a Hash, but maintains its elements in ascending key order. The interface is the almost identical to that of Hash.

The ptools (power tools) library extends Ruby's core File class with many additional methods modelled after common POSIX tools, such as File.which for finding executables, File.tail to print the last lines of a file, File.wc to count words, and so on.

Byebug is a Ruby 2 debugger implemented using the Ruby 2 TracePoint C API for execution control and the Debug Inspector C API for call stack navigation. The core component provides support that front-ends can build on. It provides breakpoint handling and bindings for stack frames among other things and it comes with a command line interface.