A facility is described for enabling workflow applications. The facility receives a request to identify an optimized resource list that identifies resources capable of performing a workflow process task. The workflow process task can be associated with a document type relating to a document associated with a workflow envelope. The workflow envelope can store multiple documents of at different document types. The facility includes a workflow engine and a simulation engine. The workflow engine performs workflow process tasks based on the tasks identified in the workflow envelope. The simulation engine can employ modeling and historical data from a workflow metrics data source to generate the optimized resource list and identify identifying resources matching the workflow process tasks identified in the workflow envelope.