Colin O'Dell has shared an interesting setup he's created to make it easier to switch between PHP versions when testing your code. In his latest post he shows how to switch the version "on cd" (directory change) with the help of some command line shell tooling.

After using phpbrew to manage my local PHP versions for a while, I got tired of re-compiling PHP after every release and decided to install multiple PHP versions side-by-side with Ond?ej Surý's PPA. One of the features I missed from phpbrew was the ability to run a command like phpbrew use php-7.2.8 to automatically change the php command to that version, so I ended up implementing this feature myself using symlinks and shell aliases.

He then walks through his end result, showing the modification of the default php symlink and aliases that can be used to dynamically switch its target. He then includes some examples of how to automate this using your application's PHP version requirements in the composer.json and a simple ZSH script that's triggered on directory change.