This project is to develop a model for cooperative work in multi-user rule-based development environments (RBDEs). RBDEs forma class of environments that assist developers in carrying out the development process. RBDEs are built on object management systems that abstract project components as objects, representing both product and process. They model the development process in terms of planning system-style rules that act on these objects. Each rule encapsulates an activity by specifying the condition that must be satisfied to initiate the activity and the effects of completing the activity. RBDEs maintain object base consistency and automatically carry out some development activities through forward and backward chaining among the rules. Most existing RBDEs are single-user; those that support multiple users isolate the users, preventing cooperation. The goal of this project is to scale up RBDEs to assist teams of developers cooperating on large-scale projects. This cooperation involves: (1) concurrency control; (2) multiple views; (3) evolution; and (4) distribution. These four problems will be solved in the context of the MARVEL RBDE. A single-user version of MARVEL has been completed, and licensed to 11 external sites. Scaling up MARVEL involves solving the four theoretical problems in addition to engineering the MARVEL architecture.
