Integrity is a simple and lightweight Continuous Integration server written in Sinatra (a DSL for quickly creating web-applications in Ruby). When commits are pushed to a Git repository, Integrity builds, runs tests, and reports the build status to each team member. It supports a variety of notifiers including Email, IRC, and Twitter.

When it comes to developing large projects with multiple team members, it’s common nowadays to set up a Continuous Integration (CI) server. CI is a development practice where developers combine their work frequently and run tests over the whole project in order to identify errors early. Wikipedia has a good summary of the practice. Read More