Helmet: A Clojure-based rules engine for stochastic demand sampling in Army force structure analysis

Designing an Army force structure - the set of equipment, personnel, and skills that define the US Army - consists of a daunting set of interacting problems. Such analyses must deal with a wide range of force structure decisions, uncertainty about the future, and account for dynamics between force structure decisions. Recent methodologies at CAA use random variables for Army force structure demands. Due to constraints and dependencies, the business rules for determining a valid demand signal require more than simple draws from canonical distributions. Further, the rule-set must be open to extension to incorporate evolving sponsor constraints. Helmet is a novel Domain Specific Language (DSL) for defining complex demand sample generators. Implemented in the Clojure programming language, Helmet provides a robust, extensible platform for building stochastic force structure demands.