Thanks for sharing and making this! I see other books I've read elsewhere on the map (and have this book) so this is very cool to see. How hard was the API to work with? It could be awesome to see "for <my amazon product> show me this graph".
Long time ago I've mad a service to show the graph - https://www.yasiv.com/#/Search?q=designing%20data%20intensiv... - but the layout is very different there.