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Writing / Collection 01 / 04 notes

Engineering judgment,
made inspectable.

Four connected field notes launched as the first collection. Each starts from a working project, links to inspectable code and primary references, and keeps an honest revision date as the system evolves.

  1. 01

    Crawlers · Reliability · 9 min read · Updated September 6, 2026

    Bounded BFS: How to Crawl Careers Sites Without Crawling Forever

    A careers URL is not a job API. The useful system is the one that discovers enough, stops on purpose, and can explain every URL it did or did not fetch.
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  2. 02

    Transactions · APIs · 8 min read · Updated September 6, 2026

    Idempotency Is a Product Guarantee, Not an HTTP Header

    The header only names a request. The database transaction, uniqueness rule, replay semantics, and side-effect boundary are what prevent a customer from paying twice.
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  3. 03

    Agents · Evaluation · 8 min read · Updated September 6, 2026

    The Model Is Never the Judge: Deterministic Agent Evals

    Language models are useful actors and useful critics. They are the wrong final authority for tenant isolation, tool schemas, write permissions, and other invariants that must not drift.
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  4. 04

    AI workflows · Durable execution · 8 min read · Updated September 6, 2026

    Human Approval in Durable AI Workflows

    A human-in-the-loop button is not a safety boundary if the process forgets the wait, the approval has no identity, or the model can call publish by another route.
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