8 best Ruby Testing Generic libraries in 2025

Ruby is one of the most popular programming languages in the world and has been used in web development for many applications. A plethora of Ruby libraries are available that can be used to test and debug applications built on Ruby. The standard tools provided by Ruby are a bit outdated and so developers are looking for alternatives. Ruby testing also helps you get more accurate feedback on your code and products, learn more about your users and buyers, and ensure that the products you create are as well-made as possible. With the right approach, testing in Ruby can become a key part of any developer/designer/marketer’s workflow. In this kit, we will cover some of the best open-source Ruby testing libraries that you should know about. Most of these libraries can be used for multiple purposes like testing, debugging, etc. slather - Generate test coverage reports for Xcode projects; active_mocker - Generate mocks from ActiveRecord models for unit tests; puppet-retrospec - generate puppet code.