A toolkit for building modeling frameworks like Active Record. Rich support for attributes, callbacks, validations, serialization, internationalization, and testing.

Email on Rails. Compose, deliver, and test emails using the familiar controller/view pattern. First-class support for multipart email and attachments.

Attach cloud and local files in Rails applications.

minitest provides a complete suite of testing facilities supporting TDD, BDD, mocking, and benchmarking. "I had a class with Jim Weirich on testing last week and we were allowed to choose our testing frameworks. Kirk Haines and I were paired up and we cracked open the code for a few test frameworks... I MUST say that minitest is *very* readable / understandable compared to the 'other two' options we looked at. Nicely done and thank you for helping us keep our mental sanity." -- Wayne E. Seguin minitest/test is a small and incredibly fast unit testing framework. It provides a rich set of assertions to make your tests clean and readable. minitest/spec is a functionally complete spec engine. It hooks onto minitest/test and seamlessly bridges test assertions over to spec expectations. minitest/benchmark is an awesome way to assert the performance of your algorithms in a repeatable manner. Now you can assert that your newb co-worker doesn't replace your linear algorithm with an exponential one! minitest/mock by Steven Baker, is a beautifully tiny mock (and stub) object framework. minitest/pride shows pride in testing and adds coloring to your test output. I guess it is an example of how to write IO pipes too. :P minitest/test is meant to have a clean implementation for language implementors that need a minimal set of methods to bootstrap a working test suite. For example, there is no magic involved for test-case discovery. "Again, I can't praise enough the idea of a testing/specing framework that I can actually read in full in one sitting!" -- Piotr Szotkowski Comparing to rspec: rspec is a testing DSL. minitest is ruby. -- Adam Hawkins, "Bow Before MiniTest" minitest doesn't reinvent anything that ruby already provides, like: classes, modules, inheritance, methods. This means you only have to learn ruby to use minitest and all of your regular OO practices like extract-method refactorings still apply.

A package (also known as a library) contains a set of functionality that can be invoked by a Ruby program, such as reading and parsing an XML file. We call these packages 'gems' and RubyGems is a tool to install, create, manage and load these packages in your Ruby environment. RubyGems is also a client for RubyGems.org, a public repository of Gems that allows you to publish a Gem that can be shared and used by other developers. See our guide on publishing a Gem at guides.rubygems.org

CoffeeScript is a little language that compiles into JavaScript. Underneath all of those embarrassing braces and semicolons, JavaScript has always had a gorgeous object model at its heart. CoffeeScript is an attempt to expose the good parts of JavaScript in a simple way.

Protect against typical web attacks, works with all Rack apps, including Rails

Pry is a runtime developer console and IRB alternative with powerful introspection capabilities. Pry aims to be more than an IRB replacement. It is an attempt to bring REPL driven programming to the Ruby language.

We use this library at GitHub to detect blob languages, highlight code, ignore binary files, suppress generated files in diffs, and generate language breakdown graphs.

Docile treats the methods of a given ruby object as a DSL (domain specific language) within a given block. Killer feature: you can also reference methods, instance variables, and local variables from the original (non-DSL) context within the block. Docile releases follow Semantic Versioning as defined at semver.org.

Wrap an option at compile-time and `call` it at runtime, which allows to have the common `-> ()`, `:method` or `Callable` pattern used for most options.

This gem aims at being a simple and reliable solution for controlling external programs running in the background on any Ruby / OS combination.

Track changes to your models, for auditing or versioning. See how a model looked at any stage in its lifecycle, revert it to any version, or restore it after it has been destroyed.

Convert directories, rpms, python eggs, rubygems, and more to rpms, debs, solaris packages and more. Win at package management without wasting pointless hours debugging bad rpm specs!

Official AWS Ruby gem for Amazon Athena. This gem is part of the AWS SDK for Ruby.

raindrops is a real-time stats toolkit to show statistics for Rack HTTP servers. It is designed for preforking servers such as unicorn, but should support any Rack HTTP server on platforms supporting POSIX shared memory. It may also be used as a generic scoreboard for sharing atomic counters across multiple processes.

This pure Ruby library can read and write PNG images without depending on an external image library, like RMagick. It tries to be memory efficient and reasonably fast. It supports reading and writing all PNG variants that are defined in the specification, with one limitation: only 8-bit color depth is supported. It supports all transparency, interlacing and filtering options the PNG specifications allows. It can also read and write textual metadata from PNG files. Low-level read/write access to PNG chunks is also possible. This library supports simple drawing on the image canvas and simple operations like alpha composition and cropping. Finally, it can import from and export to RMagick for interoperability. Also, have a look at OilyPNG at https://github.com/wvanbergen/oily_png. OilyPNG is a drop in mixin module that implements some of the ChunkyPNG algorithms in C, which provides a massive speed boost to encoding and decoding.

A rack middleware for throttling and blocking abusive requests

Generates attr_accessors that encrypt and decrypt attributes transparently

A simple gem to atomically write files