What is continuous Integration?

Continuous Integration or CI, is simply about making sure that software builds, and passes its tests, each time any coded is checked in to its Version Control repository.

Why is this useful?

We encourage people to check in their code very often, writing new unit tests and Refactoring the code all the time. When code is checked in, it is automatically built, and all the test cases are run. This simple procedure ensures that at any time, all the code in the project is working (according to the defined tests).

What does this mean?

In practical terms, this means that at any point in a project, the code could be deployed to a production system, and be expected to work - for any part of the project that had been completed. No lengthy integration phases, no code lurking on somebody's PC that will break the whole project when they check it in...

Walk away at any point

In business terms, this means that there is never any software writeoff, all the work that has been done, at any stage will work, to specification, even if it is decided for business reasons to terminate a particular software project.