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  • A readonly class that needed one mutable field, and what that meant

    Note2 min read

    A readonly value object that wanted a lazily computed cache, which is exactly what readonly forbids and is usually a signal. The wrapper is the textbook answer and…

  • A schema cached rather than migrated, per job

    Note2 min read

    188 migrations run at the start of every CI job, replaced by a dump loaded in nine seconds. The staleness check is what makes this safe, and without…

  • A test written by a tool, and read as review

    Note2 min read

    A generated test for an existing class, which is the case model assistance is genuinely good at, with one caveat. The second test asserts that assignment works, which…

  • A database per process, and the isolation it buys

    Note2 min read

    Parallel test processes sharing one database, and the transaction-per-test isolation that stops working under concurrency. Loading the schema from a dump rather than migrating is what makes eight…

  • What we do not let it near, written down

    Note2 min read

    A scope decision recorded as a rule, because a rule can be reviewed and a feeling cannot. The list is short and it is the shape that matters…

  • A transient stampede on a cold cache

    Note2 min read

    A transient holding an expensive query result, expiring at a fixed time, and four hundred requests recomputing it simultaneously. The stale copy with a longer lifetime is what…

  • Three suggestions that would have been vulnerabilities

    Note1 min read

    Six months of review findings, filtered to the ones with a security consequence. All three are patterns that appear constantly in public code, which is presumably why they…

  • The incident that was a certificate, again

    Deep dive10 min read

    The third certificate incident in six years, each with a different cause. An expired certificate on a service nobody remembered was serving TLS.

  • A plugin downgrade that was a version constraint

    Note1 min read

    A plugin update that broke a checkout flow, reverted by editing one line and running one command. A downgrade that is a version constraint and a redeploy is…

  • Anchor positioning, read and not used

    Note1 min read

    A CSS feature that solves a real problem, available in one engine, evaluated and deferred. The fallback syntax is the part that makes this genuinely better than the…