NexusBoard

NexusBoard is a small-scale but production-shaped take on Figma and Miro. The interesting engineering is not the shapes, it is the real-time, conflict-free multi-user sync and the rendering performance that keeps a canvas smooth with thousands of objects.

Business logic lives in framework-independent, tested modules, and the collaboration transport is its own standalone WebSocket service. Concurrent edits merge per-property through a Yjs CRDT, and a hand-written quadtree only draws what is inside the viewport.