just learned about https://github.com/wickman/pystachio which is apparently used for mesos config stuff within twitter:

tl;dr

Pystachio is a type-checked dictionary templating library.

why?

Its primary use is for the construction of miniature domain-specific configuration languages. Schemas defined by Pystachio can themselves be serialized and reconstructed into other Python interpreters. Pystachio objects are tailored via Mustache templates, as explained in the section on templating.