I've heard about Pure Data but here aim is to
a) emulate the feel of a real rack (to which end I am rewriting the UI from scratch)
b) relatedly, aim is to be friendly to non-programmers, cause all musicians I know can't use a computer for more than opening a DAW
"In 2001, the developer was hired by Native Instruments in order to develop Reaktor 5 with core technology."
Also, funny thing but I did not know about VCV before today :)
Have you heard of Pure Data or Max/MSP? :)