I have a fairly complex deployment of dynamically configured instances of a rail apps on nginx using passenger that I currently use Capistrano for. I am trying to automate the e
Opsworks now supports Chef 11.10 and Berkshelf (http://berkshelf.com/) to manage dependencies which makes using custom cookbooks so. much. easier.
I've been pretty happy with Test Kitchen (https://github.com/test-kitchen/test-kitchen) with Vagrant & Chef Solo for local testing.
Additionally you can manually run particular recipes on an Opsworks stack from the stack settings page. Have a look here: http://docs.aws.amazon.com/opsworks/latest/userguide/workingcookbook-manual.html.
You can also run cookbook tests during an Opsworks deployment with some custom JSON: http://docs.aws.amazon.com/opsworks/latest/userguide/troubleshoot-debug-test.html