This was a great article, and I'm a competitor! :) Learned a lot about the history. My one nit-pick is they say distributed joins are hard though. But they don

This was a great article, and I'm a competitor! :) Learned a lot about the history. My one nit-pick is they say distributed joins are hard though. But they don't really justify it other than the assumption other engineers have come from a traditional DB background. It is not a hard problem if you try to solve it on your own though: You do the join on the client, incrementally (or debounced if necessary) as the data is streamed. This works very well at scale in production (TB/day) for our system.