umarise

Anchor files to Bitcoin. Verify proofs offline.

Content-blind proof-of-existence infrastructure. Umarise never receives your file, only its SHA-256 hash.

Install

pip install umarise

Quick start (CLI)

# 1. Get your free API key at https://umarise.com/developers
export UMARISE_API_KEY=um_your_key_here

# 2. Anchor a file
umarise anchor contract.pdf

# 3. After ~2 hours (Bitcoin confirmation), get full proof
umarise proof contract.pdf

# 4. Verify — no API key needed, works offline
umarise verify contract.pdf

Expected output

$ umarise anchor contract.pdf
✓ hash computed: sha256:a1b2c3d4e5f6...
✓ anchored: origin_id f47ac10b-58cc-4372-a567-0e02b2c3d479
ℹ proof.ots pending — Bitcoin confirmation takes ~2 hours
✓ certificate saved: contract.pdf.proof
✓ receipt: contract.pdf.certificate.json

$ umarise proof contract.pdf        # after ~2 hours
✓ hash: sha256:a1b2c3d4e5f6... (already anchored)
✓ origin_id: f47ac10b-58cc-4372-a567-0e02b2c3d479
✓ anchored in Bitcoin block 943943
✓ no later than: 2026-04-06
✓ saved: contract.pdf.proof
✓ extracted: contract.pdf-proof/
✓ proof valid — independent of Umarise

$ umarise verify contract.pdf
✓ hash matches
✓ anchored in Bitcoin block 943943
✓ no later than: 2026-04-06
✓ proof valid — independent of Umarise

Python SDK

from umarise import UmariseClient

client = UmariseClient(api_key="um_your_key_here")

# Anchor a file (hash computed locally, file never leaves your machine)
result = client.anchor("contract.pdf")
print(result.origin_id)   # f47ac10b-...
print(result.hash)         # sha256:a1b2c3...

# Check proof status
proof = client.proof(result.origin_id)
if proof.status == "anchored":
    print(f"Bitcoin block: {proof.bitcoin_block_height}")

# Anchor a pre-computed hash (for pipelines)
result = client.anchor_hash("sha256:a1b2c3d4e5f6...")

# Resolve metadata (no API key required)
origin = client.resolve(origin_id="f47ac10b-...")
origin = client.resolve(hash="sha256:a1b2c3...")

# Verify a hash (no API key required)
check = client.verify("sha256:a1b2c3d4e5f6...")
if check["found"]:
    print(check["origin"])

How it works

1. Hash locally — SHA-256 is computed on your machine. Your file never leaves.
2. Anchor — The hash is submitted to the Umarise registry and queued for Bitcoin anchoring.
3. Bitcoin confirms — Within ~2 hours, the hash is embedded in a Bitcoin block via OpenTimestamps.
4. Verify independently — Anyone with the file and .proof bundle can verify. No API, no account, no Umarise dependency.

The .proof bundle

contract.pdf.proof (ZIP)
├── certificate.json    # origin metadata (hash, origin_id, timestamp, block)
├── proof.ots           # binary OpenTimestamps proof (Bitcoin anchor)
├── artifact.pdf        # copy of the original file (proof command only)
└── VERIFY.txt          # verification instructions

Important: The .proof file must be in the same directory as the original file for verify to find it automatically.

CI/CD

For automated anchoring in GitHub Actions, use the official action:

- uses: AnchoringTrust/anchor-action@v1
  with:
    api-key: ${{ secrets.UMARISE_API_KEY }}
    files: dist/build.tar.gz

→ GitHub Marketplace: Umarise Anchor

Pricing

Your API key includes 100 free anchors. No email, no account required.

For production use, see umarise.com/pricing.

Links

• Documentation
• API Reference
• Anchoring Specification
• Independent Verification
• npm CLI (Node.js alternative)
• Status

License

MIT