I’m impressed by Twitter. And, I mean, pre-Dusk Twitter.
♲ Dennis Schubert (denschub@pod.geraspora.de)2022-11-14 23:47:27:
I’m impressed by Twitter. And, I mean, pre-Dusk Twitter.
One can tell just by using it that the backend is in a very very unhealthy state. Notification unread states don’t have counters, but just an „you have new stuff“ blobb. Sometimes threads load but you can’t interact. You still get notifications that people like your tweets, but you don’t get them summarized as „Foo, bar, and X others liked your tweet“, you just see them as individual notifications.
You can tell how a significant amount of backend services are just… down. And yet, Twitter is still up. You can still post, you see notifications, messages work, … even though a lot of things are degraded, … Twitter still works.
I’m impressed by this level of defensive architecture, with that much care to handle service downtime and graceful degradation. I was part of the crowd that sometimes made fun of Twitter for being relatively slow with shipping new things, but holy heck, this is amazing. Quoting a former colleague:
It’s like the end of 2001 when Dave is destroying HAL and HAL keeps on going, just gradually degrading, but continuing to work as far as his remaining capacities allow him to.
It’s mindblowing. If you’ve never worked on complex software applications and spent time thinking about software architecture, you probably wouldn’t even notice that anything is off. Their engineers, their ops, their SREs, … they all did absolutely stunning work. It’s sad to see that so many of them have been laid off, but I know that their skills will be more than welcome in other companies.