Your desktop is the DOM.

import { startSession, StageProvider, Stage, Sprite } from 'filedom';

// Each paddle and the ball is a real file on your Desktop.
function Pong() {
  // …metrics, keys, and a 50 ms physics tick (full file: Getting Started)
  return (
    <StageProvider metrics={metrics} park={park} background={FIELD}>
      <Stage prebake={[paddle]}>
        <Sprite icon={paddle} at={{ x: 32, y: left }} />
        <Sprite icon={paddle} at={{ x: metrics.width - 32, y: right }} />
      </Stage>
      <Stage prebake={[ball]}>
        <Sprite icon={ball} at={ballAt} />
      </Stage>
    </StageProvider>
  );
}

startSession(<Pong />);