User types "android" into your search box. That's 7 API calls if you wired it the way I did the first time. A few months later I shipped a pagination bug where every infinite-scroll fetch flashed a full-screen loader for half a second. And then there was the Settings screen that needed to refresh the Dashboard when the user changed theme — but Settings couldn't import Dashboard without a circular
At 3:17 AM on a Tuesday in Q3 2024, our production Kotlin 2.0 microservice fleet hit a 92% memory utilization threshold across 140 nodes, traced to a silent coroutine leak in Ktor 2.2’s request pipeline that had been bleeding 12MB of heap per second for 72 hours. We lost $14k in SLO credits before we found the root cause. A Couple Million Lines of Haskell: Production Engineering at Mercury (78 p