Interfaces elocuentes versus DSL

Fluent interfaces are usually useful only during the development process. A fluent interface is probably a good choice if you intend to use it while you write the code, because you won't have to switch between two languages and can take advantage of the IDE tooling. In contrast, if you want to allow modifications outside development (for example, in production), a DSL tends to be a much better choice.

Building Domain Specific Languages in Boo
Ayende Rahien
Manning