An interactive design system includes a design application that creates and models a geometry of an object. A programming language application defines engineering rules that may be associated with the object. The programming language application associates the geometry of the object with the engineering rules such that any change made to the geometry is automatically reflected in the engineering rules and any change made to the engineering rules is reflected in the geometry. The programming language application may also generate one or more knowledge features that can be used to verify that associated parameter constraints have not been violated as a result of a geometry or engineering rule change before applying the desired changes.