A toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Rich support for multibyte strings, internationalization, time zones, and testing.

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

Databases on Rails. Build a persistent domain model by mapping database tables to Ruby classes. Strong conventions for associations, validations, aggregations, migrations, and testing come baked-in.

Web apps on Rails. Simple, battle-tested conventions for building and testing MVC web applications. Works with any Rack-compatible server.

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 fe...

Selenium implements the W3C WebDriver protocol to automate popular browsers. It aims to mimic the behaviour of a real user as it interacts with the application's HTML. It's primarily intended for web application testing, but any web-based task can automated.

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

An object-oriented testing framework

This gem can compare doms and assert certain elements exists in doms using Nokogiri.

Capybara is an integration testing tool for rack based web applications. It simulates how a user would interact with a website

rspec-rails integrates the Rails testing helpers into RSpec.

Strategies for cleaning databases. Can be used to ensure a clean slate for testing.

Capybara aims to simplify the process of integration testing Rack applications, such as Rails, Sinatra or Merb. It is inspired by and aims to replace Webrat as a DSL for interacting with a webapplication. It is agnostic about the driver running your tests and currently comes bundled with rack-tes...

Capybara aims to simplify the process of integration testing Rack applications, such as Rails, Sinatra or Merb. It is inspired by and aims to replace Webrat as a DSL for interacting with a webapplication. It is agnostic about the driver running your tests and currently comes bundled with rack-tes...

Helps creating valid Guard plugins and testing them

A Ruby library for controlling Toxiproxy. Can be used in resiliency testing.

Extracting `assigns` and `assert_template` from ActionDispatch.

CasperJS is a navigation scripting & testing utility for [PhantomJS](http://www.phantomjs.org/). It eases the process of defining a full navigation scenario and provides useful high-level functions, methods & syntaxic sugar for doing common tasks.

Strategies for cleaning databases. Can be used to ensure a clean slate for testing.

Hypothesis is a powerful, flexible, and easy to use library for property-based testing.