The Ledger Everyone Reads (event-driven & the log)

The chai stall’s order-slip rail (The order slip rail (queues & the utilization cliff)) grown up. There, one boy handed slips to one kitchen. Here four people all need the same order, and the rail becomes a book on the counter that nobody is allowed to erase.

Before you start. You need the order-slip rail from The order slip rail (queues & the utilization cliff): the order goes on a spike, the kitchen takes the next slip whenever it is free, and the customer walks away instead of standing there. That is one writer and one reader, and it works. The only thing this lesson changes is how many people want to read.