He is using an open source app called tldraw and this is the prompt used: https://github.com/tldraw/draw-a-ui/blob/2ac633bbbd5fda39e59935872fba00d849fa4dbf/app

He is using an open source app called tldraw and this is the prompt used: https://github.com/tldraw/draw-a-ui/blob/2ac633bbbd5fda39e59935872fba00d849fa4dbf/app/api/toHtml/route.ts https://github.com/tldraw/draw-a-ui/blob/2ac633bbbd5fda39e59...