Faker is a port of Data::Faker from Perl. It is used to easily generate fake data: names, addresses, phone numbers, etc.

HighLine provides a high-level IO library that provides validation, type conversion, and more for command-line interfaces. HighLine also includes a menu system for providing multiple options to the user.

This package provides a Ruby kernel for Jupyter/IPython frontends (e.g. notebook).

This package provides telnet client functionality.

Net::SSH is a pure-Ruby implementation of the SSH2 client protocol. It allows you to write programs that invoke and interact with processes on remote servers, via SSH2.

WebMock allows stubbing HTTP requests and setting expectations on HTTP requests. This is useful when testing software.

This package provides a subclass of Object that includes the Comparable module for handling dates.

This package provides a library to help create value objects without the pain of Ruby's Struct (or its setters).

This package provides a Ruby module that provides a two-phase lock with a counter.

Connection_pool provides a generic connection pooling interface for Ruby programs.

ChunkyPNG is a pure Ruby library that can read and write Portable Network Graphics (PNG) images without depending on an external image library. It tries to be memory efficient and reasonably fast. It has features such as:

• Decoding support for any image that the PNG standard allows. This includes all standard color modes, all bit depths, all transparency, and interlacing and filtering options.

• Encoding support for images of all color modes (true color, grayscale, and indexed) and transparency for all these color modes. The best color mode is chosen automatically, based on the amount of used colors.

• Read/write access to the image's pixels.

• Read/write access to all image metadata that is stored in chunks.

• Memory efficiency: fixnum are used, i.e. 4 or 8 bytes of memory per pixel, depending on the hardware).

• Performance: ChunkyPNG is reasonably fast for Ruby standards, by only using integer math and a highly optimized saving routine.

• Interoperability with RMagick.

ChunkyPNG is vulnerable to decompression bombs and can run out of memory when loading a specifically crafted PNG file. This is hard to fix in pure Ruby. Deal with untrusted images in a separate process, e.g., by using fork or a background processing library.

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

Multihashes provides a simple, low-level multihash implementation for Ruby. A multihash is a digest with an embedded hash function code

skiptrace provides a way to access the bindings that relate to exceptions in Ruby, providing more information about the context in which the exception occurred.

This library provides functionality to send Internet mail via SMTP, the Simple Mail Transfer Protocol. The SMTP protocol specification is known as RFC2821.

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.

This package provides a Jekyll plugin to add metadata tags for search engines and social networks to better index and display your site's content.

Timecop provides "time travel" and "time freezing" capabilities, making it easier to test time-dependent code. It provides a unified method to mock Time.now, Date.today, and DateTime.now in a single call.

Dotenv is a Ruby library for setting environment variables defined in a .env file. This is the Rails variant, adapted for use with Ruby on Rails projects.

GLI allows you to create command-line applications in Ruby with Git-Like Interfaces: that is, they take subcommands in the style of git and gem. GLI uses a simple domain-specific language, but retains all the power of the built-in OptionParser.

Bake is a task execution tool, inspired by Rake, but codifying many of the use cases which are typically implemented in an ad-hoc manner.

ruby-hydra-minimal is a Ruby library for working with hyphenation patterns. It is a low-dependency variant of ruby-hydra.

EmailReplyTrimmer is a Ruby small library to trim replies from plain text email.

The cane gem provides a great framework for running quality checks over your ruby project as part of continuous integration build. It comes with a few checks out of the box, but also provides an API for loading custom checks. This gem provides a set of additional checks.