Document seal

Demo video: Certificate and QR

by Stefania Overman ✓ signed with granted key 3391cebb120892c6sealed 2026-09-07block #23

“Official Heartwood Library demonstration video, published on the @HeartwoodLibrary YouTube channel. Any copy of the file can be verified against this fingerprint, forever.”

Sealed document: demo4-certificate-qr.mp4 (the document itself is not published; its sha256 fingerprint below is what the author sealed).

seal id: 4577c935aae0d5dda03775c24ed74d46c95d77d75223d797d4c442ce91096f08

statement sha256: ef4ff2ccf8d6e29fb2141ea10eb4fd56021e173c0dce506702400f30a0d17ec4

document sha256: 018275b591e7bca467132e048f697e715f55b8e85ae7d8ee7ea5447544a2c64c

signing key: 3391cebb120892c6 (Ed25519, granted on chain in block #8)

Check your copy

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Verify without trusting this server

The proof bundle contains the sealed block, the author’s public key, and the exact recipes. The verifier is a single dependency-free script; read it before you run it.

Proof bundle (JSON)Independent verifier (node)Signed chain tip Raw chain Open protocol spec

node verify-seal.js proof.json --document your-file

Embed the badge

Place this next to the statement on any site; it links readers back to this certificate.

<a href="https://heartwoodlibrary.org/seal/4577c935aae0d5dda03775c24ed74d46c95d77d75223d797d4c442ce91096f08"><img src="https://heartwoodlibrary.org/badge/4577c935aae0d5dda03775c24ed74d46c95d77d75223d797d4c442ce91096f08.svg" alt="Sealed in Heartwood Library" width="252" height="36"></a>

Print the QR on the document

The QR encodes this certificate’s address, so any phone camera becomes the verification entry point: print it on the cover page, the report footer, the poster. Scan, land here, check the copy. No app needed.