That's very interesting! We're currently working on the plumbing to be able to assign attributes to edges as well—right now it's only possible to style/configur

That's very interesting! We're currently working on the plumbing to be able to assign attributes to edges as well—right now it's only possible to style/configure the nodes. Once we have that though, there is another approach that you can take before you go down the path of writing your own visualizer/view: you can also log custom positions for each node. Since the node positions don't change in your case that might get you quite far by statically logging the nodes with a Sankey layout computed by your application.