A decision was made early on to use only open-source software, but "computer-assisted design (CAD) tools are still the biggest weakness in open-source, " says Merz.

Tcl in particular has been popular in the computer-assisted design (CAD) segment, and with such networking equipment vendors as Cisco and Nortel.

Bone tumor assisted diagnosis system is such a computer programme that applies the design theory and method of expert system, simulates medical expert diagnosis and treatment in bone tumor.