Verify this record

Do not take this record's word for its own integrity. Every check below runs on your machine against files this site publishes, and every command printed here is executed against the live data on every build — a command that fails stops the build rather than appearing on this page.

Today's integrity root

6db3e7c3d82916098c971640200a6c6b83a9d987d1375c3a54126d94a6e10c05

Observation hashes covered: 513
Fixed at: 2026-08-03 00:00:00Z — the day is this record's unit, so the time is a constant, not a clock reading

(i) Checks you can run yourself

These need nothing from this site except the files, and nothing from you except a shell. Download leaves.txt and root.txt first.

Recompute the root

The root is a SHA-256 Merkle tree over sorted instrument|date|content_hash lines — one line per observation that retained content. An odd node at the end of a level is promoted, never paired with itself.

python3 - <<'EOF'
import hashlib
L = [l.strip() for l in open('leaves.txt') if l.strip()]
h = [hashlib.sha256(x.encode()).hexdigest() for x in L]
while len(h) > 1:
    n = [hashlib.sha256((h[i] + h[i+1]).encode()).hexdigest()
         for i in range(0, len(h) - 1, 2)]
    if len(h) % 2:
        n.append(h[-1])
    h = n
print(h[0])
EOF

It prints the root above, or one of us is wrong — and the published data is the evidence for which, not this sentence.

Check a document against its recorded hash

Every instrument page shows the SHA-256 of the normalised text observed that day, and observations.json carries the whole series. Fetch the source yourself and compare.

(ii) Anchored by someone who is not us

A root this site publishes and this site alone vouches for fixes nothing: we could publish any number. What makes a date checkable is a third party saying it saw that value then.

The root above is timestamped by freetsa.org, a public RFC 3161 timestamp authority. We sent a hash; the authority returned it signed with its key, not ours. That is the only claim on this page whose forgery would require compromising someone else.

Authority: freetsa.org
Its stated time: Aug 3 17:42:49 2026 GMT

Token: root.tsr · chain: tsa-cacert.pem, tsa.crt

openssl ts -verify -data root.txt -in root.tsr \
  -CAfile tsa-cacert.pem -untrusted tsa.crt

What the token proves, and only this: that this exact root existed by the authority's stated time. It says nothing about who assembled it, nothing about whether the observations behind it were read correctly, and nothing about whether this record is accurate. Existence by a date is the whole claim.

Second anchor: this page is held by the Internet Archive at 20260803171421. That copy PREDATES the token above — it proves this page existed, not that the anchor did. A later capture will carry it.

A public blockchain would give the same guarantee — a value fixed at a time — and charge for consensus this record does not need. A timestamp token from a third party is that guarantee, from someone who is not us, at no cost. The absence of a chain here is a cost decision, not a capability one.

(iii) Procedure — our word, and you cannot check it

No signing key exists yet. When one does, its generation is offline and its custody is a person's, and this page will carry the fingerprint and the verification command. Both facts — that a key was generated offline and that it has stayed in one person's custody — are claims by this site that no reader can verify. A signature proves that a file came from the holder of a key and has not changed since it was signed. It cannot prove who has held that key. That limit belongs on this page rather than in a footnote, and nothing in this section is ever presented as a check you can run.

The rotation and compromise procedure is written before the first signature rather than after the first incident: how a key would be rotated.

What none of this proves

A signature proves origin, and that a file has not changed since it was signed. A timestamp proves a value existed by a date. A root proves the published data is the data the root was built from.

None of it proves the record is accurate. A status read wrongly hashes exactly as well as one read correctly, and a mistake fixed at a time is still a mistake. Accuracy is not a cryptographic property; it lives in the reading, in the human check, and in the corrections log, which is additive and never silently edits. Treating a hash as evidence of correctness is the one over-claim this page exists to refuse.

Method: how this record is maintained · the leaves and the root are at /integrity/leaves.txt and /integrity/root.txt.

Last updated: 3 August 2026