The question: what does serving cost?
Every action in the app — a search, a collection update, a report render — consumes time and resources. Without measurement, those costs are folklore: the slow page everyone complains about, the endpoint someone suspects. I wanted numbers instead of folklore, collected by the app about itself, every hour, without changing how anything behaves.
So I built first-party operations telemetry: each action records what ran, how long it took, and what resource pressure looked like around it. Rolled up hourly into summaries that answer "what's getting expensive?" at a glance.
The design: tiers, because not everything deserves the same attention
Page reads are sampled in full — they're the bulk of traffic and the shape of ordinary load. Background calls get counted, not recorded: volume without contents. Writes are logged after commit: outcomes, never bodies.
And whole categories are excluded outright — static assets, admin, ops internals, authentication payloads. The tiering is the point: full detail where it informs, counts where detail would be noise, silence where collection would be wrong.
The distinction: this is not visitor analytics
To be explicit, since the confusion is common: this replaces nothing about visitor analytics, and visitor analytics replaces nothing about this. One answers "who came and what did they look at" — a separate analytics tool handles that. Mine answers "what did serving it cost." Different questions, different instruments, both worth having.
Especially if you are going to be deploying your app to the Public Cloud. Where every inefficiency comes with true cost.
The use: measuring before optimizing
Telemetry has a standing job: prioritize real work. When pipeline or infrastructure effort needs ordering, the slowest and heaviest actions go first — decided by data, not by whoever complained loudest.
And the restraint is deliberate: identities stay hashed, query text stays truncated to the reads that need it, aggregates are published with their limits stated. Knowing what not to collect is half of measurement discipline.
The lesson
Instrument the system to guide decisions, not to decorate dashboards. A measurement nobody acts on is overhead; a measurement with stated limits that reorders your roadmap is infrastructure.