Immortalize

Anchor your Nostr identity to Bitcoin using Blocktrails technology.

What it does

Immortalize creates a cryptographic proof that permanently links your Nostr profile or notes to a Bitcoin transaction. This proof:

• Uses P2TR (Taproot) key tweaking - no OP_RETURN data bloat
• Is verifiable by anyone with the TXO URI and your public key
• Survives even if Nostr relays go offline
• Works on Bitcoin mainnet, testnet4, and Litecoin

How it works

1. Connect your Nostr identity (via extension or nsec)
2. Fund the app's faucet address (testnet4 sats)
3. Immortalize your profile or a note
4. Share the proof URI for others to verify

Technical Flow

TX1: Faucet UTXO → Genesis UTXO (your pubkey) + Change
TX2: Genesis UTXO → Anchor UTXO (tweaked pubkey)

Where: tweaked_pubkey = your_pubkey + SHA256(event_hash) × G

The anchor output's pubkey encodes a commitment to your Nostr event data.

Live Demo

https://nostrapps.github.io/immortalize

Files

• index.html - Main application
• verify.html - Proof verification page
• docs.html - Documentation

Self-Funding Faucet

The app generates a unique faucet address for each session. Fund it using any testnet4 faucet, and you can create multiple proofs from that balance.

Verification

Proofs can be verified by:

1. Fetching the anchor transaction from the blockchain
2. Computing the expected tweaked pubkey from (base_pubkey, event_hash)
3. Comparing against the actual anchor output pubkey

Built With

• Preact + HTM - UI
• @noble/curves - Cryptography
• @noble/hashes - Hashing
• Blocktrails - Anchoring protocol
• Mempool.space API - Blockchain data

License

MIT