The natural distributed character of software ecosystems calls for a shared conceptualization and language to describe their architecture and their evolution. In this regards, ontologies play a central role. In this paper: we argue in favor of such an approach by showing that there is succesful experience applying ontologies to the fields of software engineering and software architecture; show the issues arising in ecosystem evolution and the needs for higher levels of formalization of the description of such processes; finally, we present a roadmap to develop an ontology for this area.