Deneb faceted distribution plot

[asodie]

I am wondering if anyone has an idea of how to recreate the faceted distribution plot from this video: (2) Deneb: Bringing the Vega Languages to Power BI Visuals! (with Daniel Marsh-Patrick) - YouTube

It is basically a box plot overlayed with a distribution plot. I have been looking everywhere to find a way to at least make a distribution plot with no luck. I also would like help calculating all of the summary statistics in Deneb (median, interquartile range, etc.)

Here is a screenshot of what I'm trying to recreate:

[lbendlin]

what have you tried and where are you stuck?

Faceted Density Plot | Vega-Lite