Summary
In this chapter, you learned how the term environment is used rather than server because many websites these days use virtualized services. You then learned about three distinct environments used during the deployment phase: development, staging, and production.
An automated tool that is able to scan your application code for potential code breaks was introduced next. As you learned in that section, a break-scanning application might consist of a configuration file that addresses removed functionality, changes to method signatures, functions that no longer produce resources, and a set of callbacks for complex usage detection, a scanning class, and a calling program that gathers filenames.
Next, you were shown a typical twelve-step PHP 8 migration procedure that ensures a greater chance of success when you are finally ready to upgrade the production environment. Each step is designed to spot potential code breaks, with fallback procedures in case something goes wrong....