For some time now I've thought that I don't like the direction Drupal 8 development is heading in. The code base is getting larger and larger, the code is getting slower and slower and the mix of plugins and annotations that replaces hooks makes the development experience far less consistent.
On top of that, the PSR-0 "standard" means humans have to now write code that is more convenient to parse for computers than for other humans.
Over the past few months I've spent a lot of time thinking how to solve these issues and today I'm happy to announce I have a sandbox project that I hope addresses these problems. I'd like to invite you to grab and test the Drupal 8 Compatibility API.
Look at the sandbox and check out the code. Once you create a new site with it, you should be able to install and use any Drupal 6 contributed module or theme.
Some of you might be unable to use git, so I've attached a patch to this post which you can download and apply to the current Drupal 8.x source download.