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My own systemLive

KD Sign

Agreements signed on a phone, with a record anyone can check

The problem it solves

Getting an agreement signed means printing and scanning, or paying every month for a signing service you use a few times.

My own e-signature tool. The client taps the highlighted boxes, adopts a typed signature once, and the rest fill in. The signed copy gets the stamps and a certificate page, and a public page can check that a document is the one that was signed.

How it works

  1. Boxes where they belong

    The agreement arrives with highlighted boxes for every signature and date.

  2. A private link

    The client opens it on a phone or a computer, with nothing to install.

  3. Sign once

    They adopt a typed signature once, then tap each box to fill it.

  4. Review and confirm

    They check the finished document before it's signed.

  5. Everyone gets the signed copy

    With the stamps and a certificate page showing who signed and when.

  6. Anyone can check it

    A public page confirms a document is exactly the one that was signed.

See it working

Screens from a sample agreement with a made-up client.

KD Sign on a phone: a sample agreement with a highlighted signature box and a Sign here flag
Highlighted boxes show where to sign.
The Adopt your signature dialog, with a typed name and its preview
The first tap adopts a typed signature.
Review and confirm: the document, its fingerprint, the signature and the boxes, with Confirm and sign at the end
One last check before signing.
The document is signed: the signed copy, its fingerprint and a Save a copy button
The signed copy, ready to save.
Page one of the signing certificate: the envelope details and the first signer
A signing certificate at the end of the signed copy.

What it connects to

  • Your agreements and quotes (PDF)
  • Email
  • A public checking page

Under the hood

  • Cloudflare Pages Functions with an SQL database (Cloudflare D1)
  • PDF stamping (pdf-lib) and in-browser viewing (pdf.js)
  • A tamper-evident event log: each entry chained to the one before with SHA-256
  • Database triggers that block edits to the record
  • A public page that checks a document's SHA-256 fingerprint
  • An offline checker for the signing record
  • A private link for each signer, used to sign once, which expires

Who else it suits

Any business that sends quotes, agreements or forms to sign.

Ready when you are.

Answer a few quick questions and I'll come back with what I'd recommend and what it would cost.

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