Truth is important in your infrastruture. Keeping it in a central location lets you automate repetitive tasks easily, and with confidence.
Collins acts as a central Source of Truth in the Genesis Stack. It provides an object-oriented view of different infrastructure components, and exposes these through a web interface and a REST-ful JSON api.
Collins was developed by tumblr, and this fork is maintained by http://www.shopify.com.
You can find more documenatation on setting up Collins here.
Or, try out this vagrant box to avoid setting up depenencies.
Collins has a well documented REST api. The best way to learn it is to run through it.
Try the following actions using the API: