Your Unique Visitor Count Has a One-Month Shelf Life
Umami is MIT-licensed, so the identification path is readable. Where, who and when turn out to be a CDN header, a hash that expires on the 1st, and a bucket quantized to the clock hour.
Deep dive
Long-form analysis of how something actually works.
8 posts
Your Browser Agent Is Not Bound by the Same-Origin Policy
The web's oldest isolation guarantee is a string comparison. Put an agent inside the browser and it becomes a model's ability to resist a prompt injection.
Your Agent Re-Sends the Whole Conversation Every Turn
A multi-turn agent replays its entire history on every request. Caching, context editing and compaction each attack a different part of that bill — and one of them, at its defaults, made it worse.
Why increase() Returns 27.5
Prometheus reports fractional counts for counters that only ever increment by one. The reason is a specific extrapolation rule, and knowing it tells you exactly when the number can be trusted.
Hermes Agent's Learning Loop Is a Counter, a Critic and a Garbage Collector
Hermes Agent says it improves its own skills. In the source, that loop is a tool-call counter, a forked LLM review told to be active, and a curator that archives what nobody uses.
Googlebot Is Not Your Browser
Rendering is a separate, queued, stateless stage between crawling and indexing. Almost everything confusing about JavaScript and search comes from ignoring that.
Your LLM Is Two Different Machines
Prefill and decode have opposite performance characteristics, and almost everything confusing about LLM latency, cost and context limits falls out of that one split.
Your Observability Bill Is a Multiplication Problem
Cardinality does not creep up on you — it multiplies. Here is the arithmetic behind an exploding metrics bill, the four places the multiplication hides, and what actually shrinks it.