Document seal

Demo video: Free verification

by Stefania Overman ✓ signed with granted key 3391cebb120892c6sealed 2026-09-07block #21

“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: demo2-free-verification.mp4 (the document itself is not published; its sha256 fingerprint below is what the author sealed).

seal id: 577330b89d10622a3ceb995c0b67713af8a045e1acf7aebba8a744b153cec923

statement sha256: ef4ff2ccf8d6e29fb2141ea10eb4fd56021e173c0dce506702400f30a0d17ec4

document sha256: dca0600acedd2a2e40f6678af28ce48b26d9b521c3b92c3f798b007557cdf388

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

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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

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

<a href="https://heartwoodlibrary.org/seal/577330b89d10622a3ceb995c0b67713af8a045e1acf7aebba8a744b153cec923"><img src="https://heartwoodlibrary.org/badge/577330b89d10622a3ceb995c0b67713af8a045e1acf7aebba8a744b153cec923.svg" alt="Sealed in Heartwood Library" width="252" height="36"></a>

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