Tools are of paramount importance in automating software engineering tasks; although the Agile Manifesto prefers “individuals and their interactions over processes and tools”, some agile development activities make no exception and can be automated effectively and successfully. In process frameworks like Scrum or similar ones some activities are in fact quite structured and need specific tool support. Hence, it is interesting to study the combination of specific agile practices with OSS tools.In this paper we introduce the Compositional Agile System (CAS), an environment created to support iAgile and automate some of its tasks using OSS tools. iAgile is a Scrum-like model designed to develop critical systems in the military domain .