Bluemud is a mud server implemented using Java and Jython where the driver/server is in Java and the mudlib and in-game world is in Jython (the Java-based Python interpreter).
DUMB, the Diabolically Uncrashable Mud Builder, implements a lisp-like language interpreter in Java. This language is specialized to allow the most flexible MUD creation to date, and to allow 100% uptime, even during MUD development. NEW: SWING GUI