はてなブックマーク

Post-mortems, coffee, and a decade of stubborn curiosity Posted: 2025-06-03 Why I wrote the Beam Book After ten years of keeping Klarna’s core system upright I know this: a 15 millisecond pause in the BEAM can stall millions of peak-shopping payments, trigger a 3 a.m. Christmas-Eve post-mortem, and earn you a very awake call from the CEO. I wrote The BEAM Book so the next engineer fixes that pause