This project addresses improvements to Pegasus, a workflow system overlaying a workflow engine called DAGMan. These improvements will make Pegasus easy to deploy and use across a broad range of science users and environments. New debug capabilities will be added, usability will be improved, new communities of users will be directly engaged, richer workflow representations will be supported, dynamic workflows will be supported, priority-based task submission capabilities will be added, monitoring will be enhanced, and integration with emerging workflow technologies will be pursued. Intellectual merit lies in the demonstrated value to physics, astronomy, and other users. Broad impact of this proposal includes extension of the user base across new communities, including those using TeraGrid and OSG.
