Continuous integration, or CI, is a way that we can test code continuously. These systems will automatically listen for new Pull Requests and other events, and automatically run test suites, and other automatic processes.

We use a number of different CI systems: Travis CI and BeeKeeper . Normally the build status of a project is displayed as an image on the project's README file. Green means the tests have been successful, and red means they have not. Clicking the image will show you the results of these tests.