tldraw. It's built exactly for infinite canvas apps in React—custom shapes, tools, multiplayer sync, and a full UI system out of the box. npm create tldraw and you're off.
tldraw: Infinite Canvas Apps for React, Out of the Box
tldraw is built for infinite canvas apps in React—custom shapes, tools, multiplayer sync, and a full UI system out of the box. Run npm create tldraw and you're off.