let draw =
  () {
    case Dom.Canvas.fromDomElement(canvas) {
      Maybe::Just(el) =>
        {
          el
          |> Canvas.setFont("48px serif")
          |> Canvas.fillText("Hi!", 150, 50)
          |> Canvas.setDirection(CanvasDirection::RTL)
          |> Canvas.fillText("Hi!", 150, 130)
          ""
        }
      Maybe::Nothing =>
        ""
    }
  }
{
  await Timer.timeout(0)
  draw()
}
<canvas as canvas/>