COMPANY: Deutsche Börse Systems

The Deutsche Börse Systems uses TCL for performing functional tests of their application programming interfaces for all of their trading and clearing systems, i.e. EUREX, XETRA and CCP.

They have a TCL-based test application which is actually an extended TCL interpreter which can send all requests and receive data just as a real 3rd-party trading/clearing application does. They use a pretty smart approach which enables them to automatically re-generate their test application based on updated interface specifications, so they usually have zero to negligible efforts for maintenance of the test application itself.