Matthew Turland has a new post today to his site looking at the combination of three different technologies - TravisCI, Composer and VirtPHP - and an odd error he was getting from his build about a missing requirement "php".

In the first build, everything worked fine under 5.4 and 5.5, but upon getting to the composer install instruction to install project dependencies and PHPUnit, the job for 5.3 failed with some rather unintuitive output from Composer that implied it didn’t recognize the platform package requirement that I’d provided for the minimum PHP version. [...] Since the cause of my issue wasn’t immediately obvious from Composer’s output, my first thought was that I needed to begin my attempt at troubleshooting the issue by replicating it on my local machine.

This is where VirtPHP came in. This tool provides an environment where you can install and configure multiple PHP configurations and switch between them easily. It provides a "glue" between the phpenv and php-build projects to make management of the results simpler. He talks about how he configured and set up his environments...and figured out his Composer problem.