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
While working on my recent article, I had a dropdown set to display: block; only when the user hovers over it. The problem is that the dropdown still shows regardless. It was not removed from the viewport despite having display: none; applied. I inspected the dropdown in the browser’s dev tools and found display: none; — it was struck through. Upon further inspection, I discovered the parent <nav>