Similar to others, this uses data.name and vegaEmbed enhanced with Vega-View to chart the data (right from documentation).
Initially, a bug has removes the x-axis labels on load: if you have layer.encoding.x.title = null then it won't render. It's best for that to be "title": " ".
This also stores the spec in a separate file - I assuming doing this spec storage means you can't directly manipulate it in the browser.