APEL: A Graphical Yet Executable Formalism for Process Modeling

Software process improvement requires high level formalisms for describing project-specific, organizational and quality aspects. These formalisms must be convenient not only for capture but also for execution purposes. In order to fulfill these requirements and to build a software process environment capable of supporting engineering tasks we have designed a new graphical, but still enactable, formalism called APEL (for Abstract Process Engine Language).APEL is very ambitious in the sense that it aims to cover a wide spectrum of needs and approaches expressed not only in the software engineering field but also in many others such as real-time systems, object-oriented methodologies, tool integration, CSCW, workflow and information systems. It is then not surprising to see that many concepts and techniques used in APEL are borrowed from these connected fields. A major outcome of the work presented here was to integrate a broad range of concepts and paradigms in a single and coherent framework, but on the basis of a minimal set of primitive concepts which make it very easy to extend. Globally, the aspects which received most attention are: openness, reuse, scalability, human orientation and cooperative work.