OpenBooks

Verify this ledger

Every entry in this ledger is chained with SHA-256. Any change to any entry — even one character — breaks the chain, and every subsequent hash no longer matches. A nightly checkpoint publishes the latest head hash to a stable URL so anyone can independently audit the record over time.

OPENBOOKS · LIVE LEDGER CRYPTOGRAPHICALLY CHAINED · 2026 LIVE LEDGER

Demo Transparency Committee has a live, hash-chained ledger but has not yet met every requirement for a seal. The checklist below shows exactly what remains.

  • The seal is derived from data, never self-declared — the org cannot set its own tier.
  • It is backed by an append-only SHA-256 hash chain anyone can recompute.
  • The ledger head is anchored to a stable public URL so history can’t be rewritten.
  • If the chain ever breaks, the seal is revoked automatically — here and on every embed.
  • It certifies verifiability, not a rating: proof the record is intact, not a score of the org.
Chain integrity
Verified
Events
42
Last anchor
10/6/2026
Evidence coverage
0%

head f1e0d6e0618a8623982bc91161ff2007f50ae4f25030a3dc1b66277b05da875d

# verify this seal yourself
curl -s https://openbooks.fyi/api/ledger/demo-transparency/verify?from=0 \
  | jq -s '{ok: (last|.ok), scanned: (last|.scanned)}'

# compare the head to the published anchor
curl -s https://openbooks.fyi/api/ledger/demo-transparency/anchor.json | jq '.anchor.head_hash'

Issuance history. Every seal change is written to the ledger itself as a seal.issued / seal.upgraded / seal.revoked event, so the seal’s own history is as tamper-evident as the books it certifies. This page evaluates the seal live on each load and reflects the current state as of October 19, 2026.

Live chain verificationreading /api/ledger/demo-transparency/verify

Recompute this ledger's hash chain live from the public endpoint. Each entry is drawn as a block; every link is checked and marked pass or fail.

Loading…

How to verify independently

  1. Download the chain: curl /api/ledger/demo-transparency/verify?from=0
  2. Check that each row's prior_hash equals the previous row's event_hash, and that seq 0 anchors to 64 zeros. A removed or reordered entry breaks this immediately.
  3. Check the sequence numbers advance by one with no gaps — a gap means an entry was dropped.
  4. Compare the head hash to the anchor: curl /api/ledger/demo-transparency/anchor.json, and against an anchor you saved earlier to confirm history hasn't been rewritten.

What this does not prove yet. Each entry's hash is computed over fields this endpoint doesn't publish — including the entry's content and the email of whoever recorded it. So you can independently confirm the chain's structure here, and that it matches the anchor we published earlier, but recomputing an individual hash still takes our word for the inputs. We would rather name that gap than let “verify” imply more than it currently delivers.

This is a cryptographic hash chain — not a blockchain. There is no token, no consensus. Just an append-only ledger whose integrity you can check with a laptop and a hash function.

Upload a statement