CAD for microfluidics

I have been working on methods for representing a library of microfluidics parts in various open-source CAD tools. The idea is that eventually I'll put together some sort of drag-n-drop interface for scientists that don't want to deal with CAD, but understand what their protocol might require from a fluidic system.
For now I've only implemented some things using implicitCAD and verbnurbs.

Parabolic NURBS channel

USAGE: click and drag to pan around, zoom with middle-mouse button, and CTRL+click to move around.