Ask HN: What are the largest Open Source React apps?

I've been working in a React app that is growing really fast. More than libraries, what worries me the most is file structure.

I found an old reddit link (2 ya) showing some examples, but only Calypso (from WP) is a good example. The others are small and old. https://www.reddit.com/r/reactjs/comments/496db2/large_open_source_reactredux_projects/

Do you have any recommendations on file structure or links to large repos?