Consistency, convergence, and confluence are not the same

Pat Helland is one of the foremost experts on the topic.

I can see parallels of his Tandem NonStop system [0] in Cloudflare's Durable Objects. Helland was a resident distributed systems expert at Amazon and was explicitly thanked in the Dynamo paper by its authors.

[0] https://queue.acm.org/detail.cfm?id=3025012

This was a great article. I wished he devoted some time to Time, as it is a critical factor in sequential distributed consensus. Databases like CalvinDB or blockchains like Cardano absolutely depends on accurate system time to ensure ordered consistency. It’s an operations problem really, but if done wrong it becomes everyone’s problem.