Leibniz is an evolving system. The rule base is continually being refined as Leibniz users discover the need for new kinds of calculations. The open architecture of the Leibniz systems makes it relatively easy to add rules for new kinds of calculations.

Another recent addition to the system is a dialog facility. Mathematica code in the LZCompute.m package can now call a number of functions that bring up dialogs in the Leibniz front end. One function brings up a dialog that prompts the user to enter an expression. Another function brings up a dialog that will present the user with a list of choices for them to select from. By allowing the code in LZCompute.m to interact directly with the user Leibniz can begin to move beyond the simple imperative style of "put that there" or "compute this".

Over the long term, Leibniz will function as a test bed for ideas in interface design. By pointing out the limitations of the pattern-matching, drag-and-drop interface, Leibniz can point the way toward better and more powerful interface mechanisms for symbolic calculation.