At HP Cloud we use PHP and Drupal to build some of our experience. Matt Butcher recently wrote about how our Drupal based blog runs on the cloud giving an example of what we're doing. The code that powers our PHP effort lives in a HP Cloud PHP libray and a Drupal module that takes advantage of this library. Both of these now have a release.
HP Cloud PHP Library
The foundation for all of this is a PHP library that currently supports identity services, object storage, CDN, and DBaaS. Our versioning philosophy is that generally available services, like object storage, are semantically versioned. Service still in beta, like DBaaS, may have change but only if absolutely necessairy.
This library is being developed as we need it for our services. So, not every service is covered in the 1.0.0 release. But, we are using our own cloud so expect more services added to it. If you want to contribute please feel free. This project is on github and we look forward to pull requests and issues.
If you want are interested in an introduction to these services I wrote a 5 part series for the HP Cloud blog.
The Drupal Module
To make Drupal play nicely with HP Cloud we released a Drupal module that ties the PHP library into Drupal. For example, you can set public or private files to be served out of object storage rather than the file system. This works for image styles, automatically generated js and css files, and normal uploads. If a container is CDN enabled all these files will be served over CDN as well.
Feel free to dive in and take a look.
Our goal is to share what we can and grow these codebases over time. As more people pick them up and use them we look forward to incorperating even more improvements.
If you have any questions about these please feel free to ask.