The eLectures service of the University of Münster uses the open-source project Opencast as video management system. Recordings automatically go through one or multiple user-defined linear workflows (e.g. video encoding, thumbnail extraction, publication, etc.). Opencast's workflows are stored as XML files which are handcrafted. This thesis should implement a workflow editor for Opencast as a web application, which can load existing workflows, visualize them, allows edits, and can save the workflows back as XML files.