His research interests include software patterns, software architecture, language engineering, service-oriented architecture, distributed systems, and object orientation. He authored or coauthored Frag, Extended Object Tcl (XOTcl), Leela, ActiWeb, and many other open source software systems. He's coauthor of Remoting Patterns: Foundations of Enterprise, Internet, and Realtime Distributed Object Middleware (John Wiley & Sons) and Software-Architektur: Grundlagen, Konzepte, Praxis (Software Architecture: Basics, Concepts, Practice; Elsevier/Spektrum). He's also the European editor of the Transactions on Pattern Languages of Programming. Contact him at zdun@infosys.tuwien.ac.at.