kysigned

2 reviews

kysigned is open-source e-signature software that roots trust in DKIM, the signature your email provider already applies to every message, not a certificate authority or a vendor's reputation. E-signatures carry a premium because a signature must hold up later, so buyers pay whoever they trust most. kysigned never asks for trust. Upload a PDF, name your signers; they forward the document email back with "I sign this document". No signer accounts, no apps: the provider's DKIM signature is the proof. Each completed envelope becomes a self-contained signing record: the document, the DKIM-signed emails, timestamps (RFC 3161 plus OpenTimestamps) and the keys. Anyone can re-verify it offline in a browser, even if kysigned disappears. We never hold a key and cannot forge or alter anything. Use the hosted service, $0.25 a document, no subscription, first 4 free, or self-host the Apache-2.0 repository and run your own signing service. An MCP server lets AI agents create and send envelopes.