Grasshopper UI

I’m curious as to what Grasshopper’s UI was made WITH? WPF? And what would you use if starting from scratch today? I have an idea that would require vaguely similar(I don’t think similar enough to actually use Grasshopper, can’t say I’ve looked into it) node-like interactive widgets on a 2D canvas.

Grasshopper 1.0 uses WinForms and System.Drawing, Grasshopper 2.0 uses Eto.