The process
How it works
Three steps, in order. A sender prepares what needs acknowledging, a signer acknowledges it, and the result is a receipt anyone can verify. No fields to place, no account to check it.
First, the setup — a packet
Before anything is sent, a sender builds a packet: the document to be reviewed, the specific items to acknowledge, and a fingerprint computed from the exact file. The packet carries the fingerprint, not the document — the file itself stays with the sender.
1. Acknowledge
The signer reads the document as written and confirms the requested items deliberately. There are no signature boxes to hunt for — the document is the interface. An optional NightMark, presented from the signer's own device, can accompany the acknowledgment. This records that an acknowledgment occurred, at a recorded time — not who the person legally is.
2. Receipt
The acknowledgment becomes a receipt: a portable record of which document was reviewed, what was acknowledged, and the information needed to check it later. Because it carries the document's fingerprint, the receipt is tied to that exact file without containing it. Each receipt has a Receipt ID for lookups.
3. Verify
Anyone holding the receipt can verify it — free, no account. Verification recomputes the receipt from the evidence it references and confirms the pieces line up. Drop in the original file and its fingerprint is compared to the one recorded on the receipt: a match means it is byte-for-byte the file that was acknowledged. Change a single byte and the fingerprints no longer match.
Verification only ever tells you what it actually checked — that a receipt passed its integrity check, or that a file did (or did not) match the fingerprint on record. It never renders a broad verdict on a check it didn't run.
Where it fits
NightSign runs alongside your existing signing flow. It doesn't replace how you sign; it adds a privacy-preserving proof layer on top of it.