SwiftSign

AI-native e-signatures. Send, track, and seal contracts from your terminal: Claude Code, Cursor, Zed, or any MCP-aware agent. No drag handles. No per-seat fees.

Why

DocuSign assumes a person with a cursor, dragging signature boxes onto a PDF and paying per seat. SwiftSign assumes code. It is API-first and agent-native: a script or an AI agent can mint a key, send a legally binding contract, track it to completion, and pull back the sealed PDF and Certificate of Completion, end to end, without a browser.

What you get

REST API at /api/v1/envelopes, bearer-token auth, quota-enforced.
MCP server (swiftsign-mcp) with 11 tools so agents can sign documents directly, including agent self-signup and a confirm gate on live sends.
SDKs for JavaScript and Python.
Signer flow with no account required: a secure signing link, e-sign consent, and signature capture by draw, type, or upload.
Sealed PDFs with a SHA-256 hash, full audit trail, and a Certificate of Completion.
DocuSign importer so you can bring existing templates across.
Compliant under ESIGN, UETA (United States), PIPEDA, and the Ontario Electronic Commerce Act (Canada).

Use it from an agent

Terminal

claude mcp add swiftsign -- npx -y swiftsign-mcp

Code

"Send the MSA at ./contracts/Acme_MSA.pdf to john@acme.com for signing,
 with a signature field at the bottom."

The agent mints a sandbox key if it has none, places the fields, emails the signer a link, and reports back when it is sealed. See swiftsign-mcp for the full tool list.

Stack

Next.js 16.2 (App Router, Turbopack, React 19)
Prisma 7 + Neon PostgreSQL via @prisma/adapter-pg
Cloudflare R2 (S3-compatible) for PDFs and page images
Resend for transactional email
Stripe for billing (Free / Pro $15 / Team $79, monthly)
Upstash Redis for rate limiting, Sentry for error tracking

Architecture

/api/v1/envelopes: public REST API; bearer-token auth via Authorization: Bearer <apiKey>. Quota enforced (5/mo on Free, unlimited on Pro/Team).
/sign/[token] and /api/sign/[token]: recipient signing flow. No account; the signingToken is the only credential.
/dashboard/*: sender UI. Cookie session via swiftsign_session. Envelopes, billing, settings (API key, sessions), webhooks.
/api/stripe/webhook: Stripe to DB sync (subscription and plan).
/api/cron/webhook-retry: runs every 5 minutes via vercel.json to retry failed outbound webhook deliveries.

Development

bash

git clone https://github.com/shahdadk/swiftsign.git
cd swiftsign
./scripts/bootstrap.sh

The bootstrap script installs the Vercel CLI, logs you in, links the checkout to the SwiftSign Vercel project, pulls production env vars into .env.local, and runs npm install. Then npm run dev and you are operational.

Manual setup:

Terminal

npm install                  # legacy-peer-deps is pinned in .npmrc (React 19 / Next 16)
npx prisma generate          # writes the Prisma client to src/generated/prisma/
npx prisma migrate deploy    # apply schema migrations to your dev DB
npm run dev                  # dev server on port 3000

Common commands:

npm run dev: start the dev server on port 3000
npm run build: production build (Turbopack)
npm run start: run the built server
npm run lint: ESLint
npx prisma migrate dev --name <slug>: create a new migration
npx tsx prisma/seed.ts: seed a local user

Deploying to Vercel

Provision Neon (PostgreSQL), Cloudflare R2, Resend, Stripe (Pro and Team products plus a webhook on /api/stripe/webhook), Upstash Redis, and Sentry. Set the env vars from .env.local.example on the Vercel project (Production and Preview), connect the repo, and push to main. Vercel runs npx prisma generate and next build. Apply schema once with npx prisma migrate deploy. Verify at /api/healthcheck.

MCP server

The MCP server has its own repository at swiftsign-mcp and is published to npm as swiftsign-mcp.