Baptize is an extension for Capistrano, that allows for server provisioning. The API resembles Sprinkle, but the underlying implementation is quite different. Where Sprinkle tries to compile a static payload of commands and push to the server, Baptize is executed in runtime. It also reuses much more of Capistrano, than Sprinkle does. Basically, each Baptize package is a capistrano task - Baptize just adds some helpers and fancy dsl on top, to make it look declarative.
For now, there is virtually no documentation. Have a peek at sample/ for an idea of how it works.