> I’m not sure how real Twitter works but I think based on Elon’s whiteboard photo and some tweets I’ve seen by Twitter (ex-)employees it seems to be mostly the

> I’m not sure how real Twitter works but I think based on Elon’s whiteboard photo and some tweets I’ve seen by Twitter (ex-)employees it seems to be mostly the first approach using fast custom caches/databases and maybe parallelization to make the merge retrievals fast enough. I think Twitter does (or at some point did) use a combination of the first and second approach. The vast majority of tweets used the first approach, but tweets from accounts with a certain threshold of followers used the second approach.