Standards · Attestations

What is attested, and how you verify it.

Every day the pipeline runs with attestation enabled, it writes a small artifact — a digest of the print hash ledger and of the chained submission ledger as they stood that day. The artifacts are served verbatim at /api/attestations. They exist so that rewriting a ledger row later would contradict a dated digest already in a reader’s hands — the publication attests to itself less over time.

latest artifact 2026-09-09 · 13 artifacts served · writer: scripts/write_attestation.py (flag-gated, daily workflow)

Ⅰ · What is attested

digests, not data

An artifact contains no market data and no submission content — only counts, tip positions, and SHA-256 digests over the ledgers’ immutable columns:

Field	What it commits to
ledgers.print_hash_ledger.rows_sha256	A digest over every (print_date, sha256, corrections) row — the canonical hash of each daily print at first sight.
ledgers.print_hash_ledger.latest_print_date · rows	How far the ledger reached when the artifact was written — a lagging ledger is visible, not hidden.
ledgers.submission_hash_ledger.rows_sha256 · tip_seq · tip_chain_hash	The chained submission ledger's digest and tip. Each row's chain hash commits to every row before it, so the tip commits to the whole history.
ledgers.submission_hash_ledger.chain_intact	Whether the chain verified end-to-end when the artifact was written; defects would be listed, not suppressed.

Verification timestamps are excluded from the digests, so a given ledger state always produces the same digest.

Ⅱ · How an outsider verifies

no trust in this site required beyond what you fetch

Fetch and keep an artifact. GET /api/attestations returns the latest artifact and the index of dates; GET /api/attestations/<date> is permanent for a past date. An artifact you saved yesterday is a commitment we cannot silently rewrite today — comparing your saved copy against the served one is the check.
Check the print digest against the prints. Every print is permanently served at /api/print/<date>. The ledger row for a date is the SHA-256 of that print’s canonical core; the artifact’s rows_sha256 commits to the full set of rows. A print that changed after its ledger row was digested can no longer match.
Check the submission chain tip.A submitter holds their row’s payload hash from the confirm receipt. The chained ledger’s tip commits to every row before it, and the tip appears in each day’s artifact — a removed or altered row breaks every later day’s digest, not just its own.
Compare across days.The artifacts are append-only in effect: each day’s digests must be consistent with the ledgers that produced every earlier day’s. Holding any two artifacts constrains everything between them.

Ⅲ · Scope, stated honestly

what this does and does not prove

The honesty frame

The artifacts are produced and served by The Grid itself: they prove consistency over time— that the record you can fetch today matches the record digested on a dated earlier day — and they make silent rewriting detectable by anyone who has ever saved an artifact. They are not third-party assurance; external assurance is the roadmap’s trust ceiling, and independent, widely-held copies of the artifacts are what hardens the scheme. Saving them is participation.

The artifacts also live in the project’s git history. While the repository is private, that history is not a public verification path — the served artifacts and the chained digests are. Any wording that implies more than that is wrong and gets corrected.

latest artifact: 2026-09-09 · print ledger rows 17 (latest print date 2026-09-07) · submission ledger tip seq 12

A lagging latest_print_date inside an artifact is itself information: it means the ledger writer fell behind the prints on that day, and the artifact recorded that honestly rather than papering over it.

Artifacts: /api/attestations · /api/attestations/<date> · writer: scripts/write_attestation.py (flag-gated, runs with the daily workflow) · prints: how the print is produced