Drawing is done using stateless components that exist in separate modules. For example:

# lib/pento_web/live/pento/board.ex
def render(assigns) do
    ~H"""
    <div id={ @id } phx-window-keydown="key" phx-target={ @myself }>
      <Canvas.draw viewBox="0 0 200 70">
        <%= for shape <- @shapes do %>
          <Shape.draw
            points={ shape.points }
            fill= { color(shape.color, Board.active?(@board, shape.name) ) }
            name={ shape.name } />
        <% end %>
      </Canvas.draw>
      <hr/>
      <Palette.draw
          shape_names= { @board.palette }
          id="palette" />
    </div>
    """
  end

but Phoenix LiveView documentation suggests otherwise:

You must avoid defining a module for each component. Instead, we should use modules to group side-by-side related function components.
Phoenix.Component — Phoenix LiveView v0.20.2

I don’t have much experience with stateless components so I don’t have an opinion on this yet, but I think it would be good if we respected the convention either way: putting them all together or creating separate module for each.