Send a counterproof link, match the file hash locally, and log every signature on-chain. Simple, tamper-evident approvals for any team.
Keys stay in the browser • No file uploads • Immutable blockchain receipts
Every counter-signature is verified locally, recorded on-chain, and paired with the original proof automatically.
Create the original Solana proof from Pro. The document hash becomes the source of truth for every future signature.
Generate `/sign?hash=
Parties verify the file hash locally, sign with their Ed25519 keys, and mint a linked Solana proof. No account required.
Mutual signing keeps the original document unchanged while tracking every participant across the lifecycle of the agreement.
Files are verified client-side with SHA-256. If the bytes change, the signer is blocked before anything reaches the blockchain.
Every counter-signature lands in the audit table with wallet, timestamp, transaction link, and optional Pro user account association.
Private keys never leave the browser. Counter-signers can load saved keys, generate new pairs, and store them separately from the original owner.
Pro accounts instantly reflect new signatures with green status badges, signature history modal, and blockchain explorer shortcuts.
Replace version chaos and overnight couriers with a living audit trail that is always verifiable.
Timestamp every signature on-chain for agreements that demand provable sign-off without changing the file that was negotiated.
Route documents through procurement, compliance, and leadership with a single verification link and clear audit history.
Notaries publish the original proof, clients counter-sign, and everyone leaves with a transaction receipt that cannot be disputed.
Included with Pro. Unlimited counter-signing while we are in open beta.
Unlimited counter-signers, blockchain receipts, and dashboard tracking.
Ready in under 2 minutes • No card required during beta
Keep your contracts immutable, provable, and instantly verifiable by every party.