Some might think of DataMapper as a better, faster, competitor to ActiveRecord. However, they would be missing on of its greatest strengths. At its core, DataMapper provides a uniform interface on top of ANY persistance layer. All thats needed is a simple adapter class that can translate the native persistance into a simple 4-method API for DataMapper to consume. This talk will cover that API, and some best-practices on implementing an adapter. We will explore the YAML Adapter, which I will be writing for the purposes of this talk.