Abstract : This paper describes the first implementation of an interpreter for iRho, an imperative version of the Rewriting-calculus, based on pattern-matching, pattern-abstractions, and side-effects. The implementation contains a parser and a call-by-value evaluator in Natural Semantics; everything is written using the programming language Scheme. The core of this implementation (evaluator) is certified using the proof assistant Coq. Performances are honest compared to the minimal essence of the implementation. This document describes, by means of examples, how to use and to play with iRho. The final objective is to make iRho a, so called, agile programming language, in the vein of some useful scripts languages, like, e.g. Python and Ruby, where proof search is not only feasible but easy.