SignKit

SignKit is an open-core, Markdown-native agreement and electronic-signature platform. Agreements are ordinary Markdown documents with a real Git history, and the browser UI, AI agents, and integrators all drive the same versioned application API.

Project status

SignKit v0.1.0 is production-ready for self-hosted electronic-signature workflows on Node/Docker and Cloudflare Workers.

Shipped in v0.1.0:

• Instance-scoped Envelope API with Markdown drafts under bounded Git history, recipient readiness, send/void/reissue, and recipient decisions (view, decline, approve, sign)
• Deterministic executed agreement PDFs rendered from the pinned revision, with immutable completion artifacts and hash-chained audit evidence re-derived from Git plus SQL
• Fail-closed secure bootstrap (configured owner email; local-only unsafe opt-in), d6e-auth OAuth, owner-bound API-key agent access, and signed retryable webhooks behind a deployer allowlist
• PostgreSQL 18 and D1 migrations with parity suites, S3-compatible and R2 object storage, durable background drains with bounded leases, and backup/restore runbooks for PostgreSQL/S3 and D1-Time-Travel/R2
• First-party Rust CLI (signkit under cli/) and the Cloudflare deployment CLI (create-signkit --cloudflare ...) that reconciles Worker/D1/R2 from GitHub Releases

Scope: SignKit is an electronic-signature workflow service. A configured external provider and independent validator can optionally add a PAdES B-B or RFC 3161-backed B-T instance seal to the completed PDF. That instance signature does not turn recipient decisions into certificate-backed or qualified electronic signatures; B-LT/B-LTA are not supported.

Core ideas

• Markdown documents, Git history. Each envelope owns one Git repository of documents/*.md. Drafts are committed with expected-generation concurrency, and sending pins an immutable commit that every later read and evidence artifact resolves from.
• Agent- and API-first. There is no private UI backdoor: the first-party interface calls the same /api/v1 commands agents do. Mutations require an Idempotency-Key and the expected state or Git generation, and errors are RFC 9457 problem documents.
• Self-hostable and open. The core is AGPL-3.0-only and runs on your own infrastructure. Security and evidence collection are never paywalled.
• Portable targets. One codebase builds separate artifacts for Node/Docker, Cloudflare Workers, and Vercel behind the same domain-shaped ports.
• Evidence that states its own limits. Audit events are append-only and hash-chained, and completion artifacts are re-derived from the pinned commit plus SQL evidence. This is a re-derivation guarantee, not a tamper-proof claim.

Quick start

pnpm install
pnpm exec playwright install chromium
cp .env.example .env
pnpm run dev

Fill in .env with your d6e-auth client, encryption keys, public origin, and PostgreSQL/S3 settings before exercising anything beyond the shell. See docs/development.md for tests, builds, and the Cloudflare local loop.

Deployment profiles

Target	Database	Object storage	Background work	Status
Node/Docker	PostgreSQL 18	S3-compatible	host scheduler calls drains	supported
Cloudflare Workers	D1 binding	R2 binding	one-minute scheduled trigger	supported
Vercel	PostgreSQL	S3-compatible initially	platform-specific, unspecified	CI-only, backlog

DEPLOY_TARGET selects the profile at build time; there is no universal runtime build. Vercel compiles in CI but is experimental and not supported for production. Details in docs/deployment.md.

Agent skills

SignKit provides two repository-packaged agent skills. Users can discover and install them with npx skills add https://github.com/d6e-ai/signkit:

npx skills add https://github.com/d6e-ai/signkit

• signkit-api — Calling the /api/v1 HTTP API, capability discovery, instance-scoped API-key reads and authoring/send mutations, UUIDv7 validation, and RFC 9457 error handling.
• signkit-cli — Building, configuring, and operating the agent-first Rust CLI (signkit), credential hygiene, loopback networking, mutations, DOCX import/export, and exit codes.

Documentation

• docs/architecture/ — normative architecture, security, and evidence contracts.
• docs/api.md — current HTTP surface and its operational semantics.
• docs/cli.md — agent-first Rust CLI reference, commands, security, and exit codes.
• docs/create-signkit.md — Cloudflare deployment CLI (create-signkit), distinct from the Rust API CLI.
• docs/deployment.md — deployment profiles, configuration, and background jobs.
• docs/development.md — local setup, tests, builds, and CI expectations.
• docs/operations/ — D1 Time Travel and R2 restore runbooks.

License

AGPL-3.0-only. See LICENSE and THIRD_PARTY_NOTICES.md.