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The Real Problem: When Side Effects Matter More Than Data While working on the billing pipeline, I had a straightforward goal:Listen to events from Kafka and send billing reports to customers. Simple on paper.Until I started thinking about what coul...

It was one of those post-release mysteries.A customer’s order had gone through — payment captured, inventory updated, database neatly committed. Everything looked perfect… until downstream systems started acting like the order never existed. No confi...
