The DevOps Handbook

10Enable Fast and Reliable Automated Testing

At this point, Development and QA are using production-like environments in their daily work, and we are successfully integrating and running our code into a production-like environment for every feature that is accepted, with all changes checked in to version control. However, we are likely to get undesired outcomes if we find and fix errors in a separate test phase, executed by a separate QA department only after all development has been completed. And, if testing is only performed a few times a year, developers learn about their mistakes months after they introduced the change that caused the error. By then, the link between cause and effect has likely faded, solving the problem requires firefighting ...