Events & Symposium - Symposium - 2019 - Speakers



Speaker Michael Cowlishaw - <mfc (at) speleotrove (dot) com>
Credentials Mike Cowlishaw has worked in both hardware and software design and is currently the Editor of the IEEE 754 Standard for Floating-Point Arithmetic. He has long been interested in the human aspects of computing, including the Rexx and Java programming languages, colour perception, neural networks, text editing, mapping, panorama viewers, and decimal arithmetic. He is an IBM Fellow (retired), a Fellow of the Royal Academy of Engineering, and a Visiting Professor in the Department of Computer Science at the University of Warwick, UK.

Speaker Tracy Dean - <tld1 (at) us (dot) ibm (dot) com>
Credentials Tracy Dean is an IBM Offering Manager, primarily responsible for z/VM Tools and IMS Tools. On her first day at IBM as a summer intern in 1983 she was asked to learn REXX to write some prototype code on VM/SP for usability testing. While not a REXX expert, she enjoys teaching REXX at various Z conferences. Her organization is also responsible for the IBM REXX Compiler and Library products.

Speaker Gil Barmwater - <vicepresident (at) rexxla (dot) org>
Credentials Gil Barmwater is a retired independent computer consultant who has used Rexx since it first became available within IBM. In addition to programming Rexx in the mainframe environment, he has developed Rexx solutions on OS/2 and multiple versions of Windows. Learning about the features of ooRexx and making contributions to its ongoing development is his current interest. He currently is the Vice President of the Rexx Language Association and is its acting Secretary/Treasurer.

Speaker Rony G. Flatscher - <rony.flatscher (at)>
Credentials Rony works as a professor for Business informatics ("Wirtschaftsinformatik") at the Vienna University of Economics and Business Administration (Wirtschaftsuniversität Wien) and uses Open Object Rexx for teaching Business Administration and MIS students the object-oriented paradigm, as well as remote-controlling (automating) Windows and Windows end-user applications (e.g. MS Office, Open Office) as well as Java and Java applications (he is the author of BSF4ooRexx, the ooRexx-Java bridge, which uses Apache BSF and had Rony invited to become an ASF member). He consults and trains in all of his research fields.

Speaker René Vincent Jansen - <rvjansen (at)>
Credentials René has used Rexx since it appeared in TSO Extensions in the second half of the eighties when he was a systems programmer at the Central Bank of The Netherlands. He is an independent consultant since the turn of the century, specializing in models and meta models in order to rationalize data governance and model driven development. He likes to program in any language as long as it's Rexx.
He currently is the President of the Rexx Language Association and is a member of the Symposium Planning Committee.

Speaker Mark Hessling - <mark (at)>
Credentials Mark has significant involvement in several Rexx-related Open Source projects including the Regina Rexx interpreter and THE (The Hessling Editor). Mark is the author of several Rexx external function packages, such as Rexx/SQL, Rexx/DW, Rexx/gd, Rexx/CURL, Rexx/Curses, Rexx/Trans, Rexx/Wrapper. Mark is also the current principal maintainer of The Regina Rexx Interpreter.
In his spare time, Mark is the Webmaster for RexxLA, and is a Volunteer Fire Fighter.

Speaker Jon (Sahananda) Wolfers - <jon.wolfers (at) >
Credentials Jon met Rexx on CMS back in the 1980's whilst working for British Airways. He trained TPF programmers in the '"new" language. For the last two decades he has been producing a variety of applications in ooRexx. He has used ooRexx as the glue to link systems as well as standalone applications for as diverse requirements as shop replenishment and warehouse picking to managing bookings for a yoga studio.