Field notes / Engineering judgment

Technical opinions with consequences.

These are the decisions that separate a demo which impresses from a system worth running.

Original notes · no generic AI trend summaries

01Evaluation2026-07-23

A model metric is not an operating result.

The useful metric is attached to a decision, an error cost, and an accountable owner.Read the note

02Architecture2026-07-23

Reliability, latency, privacy, and observability often matter more than leaderboard distance.Read the note

03Product2026-07-23

Its job is to answer the expensive question before production architecture hardens around an assumption.Read the note

These positions come from projects that went badly before they went well. If your situation contradicts one, we would rather hear it than defend it.