Vaadin 8 Grid samples with code is where?

I viewed " Demo: The Commit Browser - visualize your full Git history " and would like to explore the features for Vaadin 8 Grid, but I cannot see any code with the samples.

video notes:
https://www.useloom.com/share/1bee40d20e844c1db9abe62e3fbcce17

Would this be in the new Book of Vaadin for Vaadin 8 ?

URL locations:


http://demo.vaadin.com/commit-browser/