Well sure there is "ORDER BY" something, and there are batch jobs to calculate this something from different variables. Maybe it is partially a ML black box, but I'm pretty sure they are not flying completely blind. There's got to be an internal Wiki or some PPTs where they list what goes into the mix. Number of likes, retweets. Attached media, hashtags, trending or not. Do they do sentiment analysis and use positivity as a factor? Do they do PageRank so that likes from important people have more weight? Are there manual debuffs for certain topics? Are certain posts removed or added in a second pass? These are all answerable questions in principle.

Maybe not. It could all be event-driven, distributed, and just pulling off various prioritized queues.

that's still an algorithm

We'll, it's ok if you feel that way given this is entirely subjective, but I disagree based on experience.

I disagree b/c: That's a system. An algorithm is designed, a system will emerge from pieces. An algorithm can be defined, a system's behavior has to be characterized post-hoc. You can characterize a system, but only as a black/gray box. An algorithm has invariants and stateful steps, a system has nearly infinite state and nearly zero meaningful invariants.

The trouble is, there could be literally millions of ORDER BY queries. Hell, each user could be given a fine-tuned cnn…

In the end, it's still code that is being executed, which can be called "an algorithm". Algorithms are under no obligation to be simple or only include "one algorithm".

So then "open sourcing the algorithm" likely means opens sourcing the entire Twitter codebase?

At this point, what harm would that do to Twitter? The company's tech has been stagnant for years, and the only real features recently have been attempts to exploit Twitter's network effects to ape Clubhouse & Substack. (Seems successful for the former, kind of a failure for the latter.)

do we know? has any angy ex-twitter engineer revealed the secret sauce to the world?

The aggregate of a set of systems that maps inputs and state to outputs and state updates is...

still a system that maps inputs and state to outputs and outputs and state updates.

A collection of algorithms is just a bigger algorithm.