Here is another New York Times feature story that uses all kinds of cool code tricks to add interactivity:
Note that the developers did use a framework for this page — it was Foundation, not Bootstrap. They used JavaScript to detect older versions of the IE browser.
They used a JavaScript library named FT Scroller for the scrolling interactions.
There’s a bunch of custom JavaScript to accommodate mobile, disable scrolling effects, and more.
You can even find some code you will recognize if you view source:

