OpenSignLabs/OpenSign
OpenSign
OpenSign is a self-hosted, open-source document signing platform that enables users to send, sign, and manage PDF documents with digital certificates and encryption. It functions as a complete e-signature solution, allowing organizations to run their own signing service on private infrastructure while maintaining full control over their data and document workflows.
The platform supports sequential multi-signer workflows, where documents can be sent to multiple recipients in a predefined order, with each signer receiving an email-based one-time password for verification before accessing the document. Documents are rendered and annotated directly as PDFs, supporting hand-drawn, typed, or uploaded signature images through an advanced signing pad. The system includes a document audit trail that logs all activities with timestamps, IP addresses, and email IDs, and generates completion certificates for signed documents.
OpenSign provides a REST API for integrating signing workflows into existing systems, along with webhook notifications that push real-time document status changes to external services. It connects with cloud storage and CRM platforms through Zapier and other integration tools. The application is deployed as a single Docker container configured entirely through environment variables, with documents stored in any S3-compatible object store and an automatic fallback to local filesystem storage. Users can create and reuse PDF templates, organize documents in folders, manage contacts in an address book, and set document expiration periods with the option for signers to reject signing with a reason.
Features
- Certificate-Based Document Signings - Apply a PFX or P12 certificate to digitally sign documents, supporting both self-signed and AATL-approved certificates.
- Certificate-Based PDF Signatures - Applies PFX or P12 digital certificates to PDF documents for cryptographic signature verification.
- Document Signing Workflows - Sending documents for signature, managing signer order, and tracking completion with audit trails and certificates.
- Signing APIs - Provides a programmatic REST API for embedding document signing workflows into external applications.
- Open Source Productivity Alternatives - A self-hosted document signing platform that replaces DocuSign with PDF e-signature workflows and API integration.
- PDF Annotations - Adds hand-drawn, typed, or uploaded signature images to PDF documents using an advanced signing pad.
- PDF Annotation Rendering - Renders documents by parsing and manipulating PDF files directly using a low-level PDF library for annotation and signature placement.
- Signature Capture Methods - Adding hand-drawn, typed, or uploaded signature images to PDF documents using an advanced signing pad.
- E-Signature - Store, organize, and archive digital documents inside a centralized secure vault.
- Private Infrastructure Hosting - Installs and runs the application on private servers to maintain full control over data and configuration.
- E-Signature Platforms - Running a private document signing service on your own infrastructure to keep data fully under your control.
- Mailgun and SMTP Email Deliveries - Deliver notification emails using either the Mailgun API or a custom SMTP server, toggled by a configuration flag.
- Email OTP Guest Signer Verifications - Require guest signers to enter a unique code sent to their email before they can sign a document.
- PDF Security and Signing - Signs PDF documents with robust encryption, supporting unlimited signatures even on a free cloud-hosted version.
- Email Verification Flows - Authenticates guest signers by sending a one-time password via email before granting document access.
- E-Signature Request Dispatchers - Create and dispatch a signing request to one or more recipients via email, tracking their progress through the signing workflow.
- Sequential Signing Workflows - Sends signing links to multiple signers and enforces a sequential signing order for document completion.
- Document Activity Logs - A logging service that records document activities with timestamps and generates completion certificates.
- Webhook Notifications - Set up and manage webhook endpoints to receive real-time events about document status changes.
- Signature Request Lifecycle Management - Creates, sends, and manages the lifecycle of documents that require one or more signatures.
- Document Templating - Creating and reusing PDF templates to streamline repeated e-signature collection processes.
- Centralized Document Archives - Storing, organizing, and archiving digital documents in a centralized vault with S3-compatible storage support.
- S3-Compatible Cloud Storage - Upload and retrieve documents from S3-compatible storage with an option to fall back to local storage.
- Webhook Notification Systems - Pushes real-time document status changes to external systems through configurable HTTP callback endpoints.
- S3-Compatible Storage Adapters - Stores documents in any S3-compatible object store with automatic fallback to local filesystem storage.
- Environment Variable Configuration - Loads all application settings from environment variables at startup, enabling deployment without configuration files.
- Docker Application Deployments - Packages the entire application as a single Docker container with environment variable configuration for instant deployment.
- Webhook Integrations - Connecting document signing workflows to external systems via programmatic API and real-time webhook notifications.
- Document Activity Logs - Log detailed document activities with timestamps, IP addresses, and email IDs, and generate a completion certificate.
