Abstract : Architecture Description Languages (ADL) provide descriptions of a software system in terms of its structure. Such descriptions give a high-level overview and come from the need to cope with arbitrarily complex dependencies arising from software components.In this paper we present Painless, a novel ADL with a declarative trait supporting parametrized specifications and architectural reconfigurations. Moreover, we exhibit its reliable facet on its integration with ProActive — a middleware for distributed programming. This is achieved by building on top of Mefresa, a Coq framework for the reasoning on software architectures. We inherit its strong guarantees by extracting certified code, and subsequently integrating it in our toolchain.