1. A method comprising: receiving, in a graphical user interface area, first inputs specifying drag-and-drop operations with respect to icons representing documents, the drag-and-drop operations indicating that the documents are to be added to a workflow represented by the graphical user interface area; depicting the documents within the graphical user interface area in a particular order, wherein the particular order reflects dependencies between the documents, the particular order indicating at least that processing of a second document of the documents is dependent upon an output of a first document of the documents; processing the workflow to generate a first output for the workflow, wherein processing the workflow comprises at least iteratively generating outputs for each document of the second document and the first document, in accordance with the particular order; receiving, via the graphical user interface area, second input that results in a change to the output of the first document; based upon the change, reprocessing the workflow to generate a second output for the workflow, wherein the second output differs from the first output as a result of the change; wherein the method is performed by one or more computing devices.