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.

The Listen gem listens to file modifications and notifies you about the changes.

BRASS (Bare-Metal Ruby Assertion System Standard) is a basic foundational assertions framework for other assertion and test frameworks to make use of.

Pg is the Ruby interface to the PostgreSQL RDBMS. It works with PostgreSQL 9.3 and later.

Bond can autocomplete argument(s) to methods, uniquely completing per module, per method and per argument. Bond provides a configuration system and a DSL for creating custom completions and completion rules. Bond can also load completions that ship with gems. Bond is able to offer more than irb's completion since it uses the full line of input when completing as opposed to irb's last-word approach.

Sucker Punch is a single-process Ruby asynchronous processing library. It is perfect for asynchronous processes like emailing, data crunching or social platform manipulation; and generally recommended for jobs that are fast and non-mission critical like logs, emails, etc.

Pygmentize provides a simple way to call pygmentize from within a Ruby application.

ruby-unf is a wrapper library to bring Unicode Normalization Form support to both Ruby and JRuby. It uses unf_ext on CRuby and java.text.Normalizer on JRuby.

This Ruby module allows you to map simple HTML back into Markdown---e.g., if you want to import existing HTML data in your application.

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.

Hamster provides 6 persistent data structures: Hash, Vector, Set, SortedSet, List, and Deque (which works as an immutable queue or stack).

Aruba is an extension for Cucumber, RSpec and Minitest for testing command-line applications. It supports applications written in any language.

Braintree provides resources and tools for developers to integrate Braintree's global payments platform.

The test-queue module is a parallel test runner, built using a centralized queue to ensure optimal distribution of tests between workers. It is specifically optimized for Continuous Integration (CI) environments: build statistics from each run are stored locally and used to sort the queue at the beginning of the next run.

This gem provide built-in support for the Sass converter in Jekyll.

Kramdown is a library for parsing and converting a superset of Markdown. It is completely written in Ruby, supports standard Markdown (with some minor modifications) and various extensions that have been made popular by the PHP Markdown Extra package and Maruku.

This package provides a gem to convert LaTeX input to Unicode. Its original use was as an input filter for BibTeX-Ruby, but it can be used independently to decode LaTeX. Many of the patterns used by this Ruby gem are based on François Charette's equivalent Perl module LaTeX::Decode.

RubyProf is a fast code profiler for Ruby. Its features include:

Speed

Being a C extension, it is many times faster than the standard Ruby profiler.

Measurement Modes

It can measure program wall time, process time, object allocations and memory usage.

Reports

A variety of text and cross-referenced HTML reports can be generated.

Threads

Profiling multiple threads simultaneously is supported.

This library contains some useful functionality to support the development of Ruby gems.

Dalli is a high performance pure Ruby client for accessing memcached servers. Dalli supports:

• Simple and complex memcached configurations

• Fail-over between memcached instances

• Fine-grained control of data serialization and compression

• Thread-safe operation

• SSL/TLS connections to memcached

• SASL authentication.

The name is a variant of Salvador Dali for his famous painting The Persistence of Memory.

Bio-logger is a wrapper around Log4r adding extra logging features such as filtering and fine grained logging.

EventMachine implements a single-threaded engine for arbitrary network communications. EventMachine wraps all interactions with sockets, allowing programs to concentrate on the implementation of network protocols. It can be used to create both network servers and clients.

Bump provides commands to manage Rubygem versioning, updating to the next patch version for example.

Psych is a YAML parser and emitter. Psych leverages libyaml for its YAML parsing and emitting capabilities. In addition to wrapping libyaml, Psych also knows how to serialize and de-serialize most Ruby objects to and from the YAML format.