Notes on agents, inference systems, and measurement. Written when a result surprised me, or turned out to be measuring the wrong thing.
An inference server stays fast by treating every request as its first. vLLM's agentic layer puts the memory beside the engine, and most of its design follows from one rule about who owns the history.
An agent that grades its own work is a control loop whose sensor sits inside the plant. Every time I fixed my evaluation, it started rewarding a different degenerate agent.
An SGLang result survived every rerun and vanished only when I timed the right interval. Nsight and source tracing revealed when KV-cache pages actually matter.
A generated paper can look finished and be wrong in the two places nobody checks. The useful engineering is the part that fails the build.
A focus tracker that reads your pulse through the webcam and decides when to interrupt you. The signal took a month. The interruption is a different kind of problem, and I turned it off within a day.
Song-dynasty supernatural tales were classed as trivial anecdotes. They are full of geographic and social detail, because a haunting needs an ordinary world to interrupt.