STINGER SI-Net
E-signature for contractors, with proof that holds up.
The e-signature service you'd otherwise pay per envelope for — except the signed PDF, its certificate, and the hash that proves it wasn't altered all land on your own disk. No account for the signer to create. No per-signature fee.
Live
SI-Net's real sign-in.
Sending is owner-gated · the signing page itself needs no account at all
How it actually works
Three steps, and the middle one happens on their phone.
You send the envelope
Point it at a PDF, name the signer, give it a subject. The envelope is registered before anything is emailed, and it gets a link carrying a 256-bit random token — not a guessable document number.
They open a plain black-on-white page
The document renders inline. They tick one consent box, then type their name or draw it. No app, no password, no account to create. The Sign button stays disabled until both the consent box and a signature are actually there.
The consent text names the statutes
The federal ESIGN Act, 15 U.S.C. Chapter 96, and Florida's Uniform Electronic Transaction Act, Fla. Stat. § 668.50. It states plainly that the typed name is the binding signature and that a certificate recording the time, the IP address and the device will be appended.
Location is offered, never required
The page asks for a rough coordinate and waits about four seconds. Declining it does not block signing — the certificate simply records that it was declined or unavailable.
The proof
What proof does an e-signature audit trail actually need to hold up?
Hashed before and after
A SHA-256 digest is taken of the document as it was sent and of the document as it was signed. Both are printed on the certificate, so the receipt proves the integrity of the exact file it's attached to.
A timeline, not a timestamp
Envelope created, invite dispatched, consent accepted, signature stamped — each with its own UTC time, and the signer's IP and device on the last two. The certificate is appended as the final page of the signed PDF, and the same events are readable from the envelope's audit endpoint.
The bytes land before the email does
The signed PDF is written to disk before any notification is attempted, so a broken mail server can never cost you the signature. If the copy to the signer fails to send, that failure is logged loudly rather than swallowed.
Signing twice does nothing twice
Reopening a signed link returns the existing result instead of stamping a second signature. If two completions race, the loser's file is deleted rather than left behind as a document that looks signed but was never recorded.
Refusals
The things it declines to do are the point.
It will not fetch a document from the internet
Send-for-signature takes a local file only. Hand it an http or https address and it refuses, so a hostile string can't make your server pull a document from somewhere else and put your name on it.
No consent, no signature
An unchecked consent box is a rejected request on the server, not just a greyed-out button in the browser. A typed name under two characters is rejected the same way.
The stamp has to fit the page
A signature box that would fall outside the target page is refused rather than clipped. Encrypted PDFs are refused rather than half-processed.
Sending is owner-only
Creating an envelope requires an owner session and is rate-limited. Signing is public by necessity — that's the whole point of the link — and the two paths are kept deliberately separate.
What's real vs. what's roadmap
Ships switched off, and the screens are honest about which ones have data behind them.
Off by default, on purpose
The whole service sits behind a flag that ships closed, so a stray merge cannot email one of your clients. With the flag off, the signing page returns a plain 404 — exempt from the login gate is not the same thing as published.
The Studio is wired; the surrounding screens aren't yet
The E-signature Studio reads real envelopes and real audit trails from the server. The envelope list, envelope detail, templates and compliance-export screens are still design shells with placeholder figures on them — they are not reading your data, and we're not going to say they are.
The record is the disk, not the index
The signed PDF and its SQLite envelope row are the record. Writing a copy into the CRM is a convenience index — if that write fails, it's logged and the signature still stands.
Document preview is best-effort
The signing page rasterizes up to twenty pages so the signer can see what they're signing. On a container without the rendering library, it says so and tells them to review the copy that was emailed — it does not quietly show a blank frame.
How it compares
SI-Net against DocuSign, Dropbox Sign, and Adobe Acrobat Sign.
All four skip the signer account — that part's table stakes now. Where SI-Net differs: the signed record and its certificate land on your own disk instead of living only in a vendor's cloud, and there's no per-envelope fee.
| Feature | SI-Net | DocuSign | Dropbox Sign | Adobe Acrobat Sign |
|---|---|---|---|---|
| Certificate carries a SHA-256 hash of the document, taken both before AND after signing | Yes | Partial/unclear from public page | Partial/unclear from public page | Partial/unclear from public page |
| Full timeline: UTC timestamp plus signer IP and device at every step | Yes | Partial — IP and location confirmed; device/per-step detail unclear | Yes | no by default — must be manually enabled by an admin |
| Signer needs no account to sign — a plain secure link is enough | Yes | Yes | Yes | Yes |
| Consent screen names the specific federal and state e-signature statutes | Yes | Unclear from public page | Unclear from public page | Unclear from public page |
| No per-signature or per-envelope fee | Yes | no — capped tiers, overage billed pay-as-you-go | yes — unlimited on Essentials and up | yes, per Adobe’s own claim |
| Monthly cost | No | $30/user/mo (Standard) | $15–$25/mo | $16.99/mo (bundled with PDF editing) |
| Signed record kept on your own infrastructure, not locked in a vendor’s cloud | Yes | no — cloud only | Unclear from public page | no — cloud only |
Competitor figures pulled from each vendor's own pricing/feature pages, 2026-09-03. SI-Net features drawn from what's live today per this page and the internal capability catalog.
Where it fits
Write it. Sign it. Keep it.
SI-Net is the second half of quote-to-cash: Galley drafts the proposal, SI-Net closes it with a signature that carries its own evidence. Same Stinger account, no per-document charge, and the certificate lives on your disk rather than in someone else's.
Related: pair SI-Net with Galley for the proposal that gets signed, or see how it fits inside the full Stinger platform.