The most amazing test suite ever written is useless if it sits on someone's laptop and is never executed! Having our tests in CI is not only beneficial to the quality of the application, but it is also beneficial to the quality of the test suite itself. By executing the test suite dozens of times a day we can discover test instabilities, which occur once in a while.
There are five components to setting up a Continuous Integration system. They are listed in order of importance here: