Document seal

Demo video: Sign in with your key

by Stefania Overman ✓ signed with granted key 3391cebb120892c6sealed 2026-09-07block #24

“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: demo5-sign-in.mp4 (the document itself is not published; its sha256 fingerprint below is what the author sealed).

seal id: 6bf84064d2bc5a8bbfe9ce31906d9611d6852c7477912bfce315d49116134e1c

statement sha256: ef4ff2ccf8d6e29fb2141ea10eb4fd56021e173c0dce506702400f30a0d17ec4

document sha256: 8744a24f04f443c0279e5531e48ac1ed95e5e298a6a8e3fa12a515eb34d2f946

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

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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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<a href="https://heartwoodlibrary.org/seal/6bf84064d2bc5a8bbfe9ce31906d9611d6852c7477912bfce315d49116134e1c"><img src="https://heartwoodlibrary.org/badge/6bf84064d2bc5a8bbfe9ce31906d9611d6852c7477912bfce315d49116134e1c.svg" alt="Sealed in Heartwood Library" width="252" height="36"></a>

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