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04 / xVerify

Proof that nothing changed by accident.

Planned: xVerify would compare the before and after of a report and print exactly what changed, what did not, and what it cannot tell you.

Planned

The comparison

What is compared.

Three things, always in this order.

  • 01

    Structure

    What the report is made of — the model, the measures, the visuals — before and after the work.

  • 02

    Behaviour

    The same questions asked of both versions, across the states the audience actually uses, with every difference reported rather than sampled.

  • 03

    Closure

    Every finding from the review is re-tested against the new artefact, not just noted as addressed.

The proof

What it has to prove

  • 01

    Every observed difference maps to a declared change

    Nothing shifts in the numbers without a named reason on file for it.

  • 02

    Every finding that was false is now true

    A resolved finding is checked again, not assumed resolved because the redesign said so.

  • 03

    No measure kept its name and changed its meaning

    If a definition moved, the name has to say so — a silent rename is treated as a failure, not a detail.

The refusal

What it refuses to conclude.

The refusal

xVerify proves the absence of unintended change; it does not prove correctness.

It does not claim the redesign is better than what it replaced. It says nothing about states it did not test. And a number that was wrong in both versions verifies clean — verification is not the same claim as correctness.

Status

Where this actually stands.

Honest status

Drafted, not built.

No verification engine exists in any repository. Adversarial tests and golden reviews are drafted, the hash-manifested before/after fixture corpus it would run against already exists, and the work is estimated at 30–40 engineering days.

Status as at 2026-09-11 · Sources: existing-code inventory · X contracts · golden and adversarial tests

Next

Start where the evidence starts.

Nothing is compared until something has been reviewed first.

Start with the question

What should your report help you decide?

Two answers are enough to begin. The brief is written in your browser: email it from your own mail app, or save a copy. This site sends nothing on its own.

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