Field guide 18 · Integrity

The Tamper Test

The strongest claim on this estate is not "our records are accurate" — it is "if anyone edits our records, you will catch us." Here is exactly how an edit surfaces, and why it cannot be quietly repaired.

Before the edit — every link verifies RECEIPT 41hash 9f2a… · prev 77c1… RECEIPT 42hash b04d… · prev 9f2a… RECEIPT 43hash 51e8… · prev b04d… RECEIPT 44hash c7f0… · prev 51e8… After one field is edited in receipt 42 — the chain fails from that exact point RECEIPT 41hash 9f2a… · verifies RECEIPT 42 — EDITEDrecomputed hash ≠ b04d… RECEIPT 43prev-link broken · unprovable RECEIPT 44downstream · unprovable the verifier reports the first failing link — receipt 42 — not a vague "integrity error"
● What an attacker would need

To alter history invisibly they would need to re-sign the edited receipt and every receipt after it — which requires the private signing key — and then replace every copy held outside their control. Each additional holder of the chain multiplies the cost of the lie.

✕ What they get instead

A precise, public accusation: verification fails at receipt 42, field-level, reproducible by anyone with the ledger and the public key. Run this yourself in the tamper simulation or the live tool-call demo — the hashes there are computed in your browser.

Deletion is as loud as edits.

Removing a receipt from the middle breaks the next receipt's prev-link exactly the way an edit does. Truncating the end is caught by the chain head — sequence and head hash are published continuously by the public chain audit.

Failure is a finding, never a repair job.

A failed verification is treated as evidence — of tampering, corruption, or compromise — and is never silently "fixed." The honest outcomes are two: the chain verifies, or you know precisely where it stopped being trustworthy.

Hashes shown are illustrative; the mechanism (SHA-256 content hashes, ed25519 signatures, prev-hash chaining) is the one running behind this estate's receipts. Not a certification, customer result, or performance claim.
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