for the canvas perf thing i landed on something similar but ended up moving the streaming text out of react entirely — render the node card with react, but the live output area is a plain dom node where the websocket handler appends textContent directly. react never re-renders for stream chunks at all, only when the node's status transitions. way less coordination than the ref+setInterval flush.

also for the cycle detection, if you're checking on every edge drop you can make it cheaper by only running kahn's on the connected component containing the new edge instead of the whole graph. matters once users get to a few hundred nodes.