X now loads posts and profiles 8-13x faster on slow connections, thanks to streaming server-rendered HTML and zero JS before the first post.
The fastest JS is the JS nobody waits for. Congrats @yagiznizipli and team!
The web rewrite is working.
On a slow connection, the old X web took more than 22 seconds to show the first post on a profile. The new X web does it in 2.7 seconds. Here's how we did it, and how we're rolling it out one country at a time.