Why Twitter didn’t go down (from a real Twitter SRE)
Twitter supposedly lost around 80% of its work force. What ever the real number is, there are whole teams with out engineers on it now. Yet, the website goes on and the tweets keep coming. This left a lot wondering what exactly was going on with all those engineers and made it seem like it was all just bloat. I’d like to explain my little corner of Twitter (though it wasn’t so little) and some of the work that went on that kept this thing running.
This is a detailed post about Twitter’s caching system that Matthew and others built while working there, and it’s brilliantly summed up by commenter Johnny Manu40:
When everything works fine, they wonder why they hired you. When everything stops working, they wonder why they hired you. I.T. in a nutshell.