I kind of meant more in terms of how they work and what they can do but I suppose I could do the work in answering that question myself by figuring out how nanovg works then comparing it to what you've written.
I've been finding Patrick's pathfinder work fascinating so it's nice to have yet another project to follow.
Got it. So far my research prototype really just does filled paths and limited strokes, but the architecture should extend to a richer set of graphics primitives. Pathfinder also started out that way but recent work is building out a good chunk of the SVG imaging model. I definitely recommend checking it out, there's a good chance it'll do what you need.
I've been finding Patrick's pathfinder work fascinating so it's nice to have yet another project to follow.