Cross-platform clients for DocuSign Signature Appliance (DSA) (formerly ARX CoSign) electronic signatures via the SOAP API (OASIS DSS standard).

Originally built for the Armenian Government's EKENG CoSign appliance, but works with any CoSign / DSA server that exposes the DSS SOAP endpoint.

+-------------------+
|  Python client    |----+
+-------------------+    |    SOAP/TLS         +-------------------+
                         +------------------->  |  CoSign appliance |
+-------------------+    |                      |  (any server)     |
|  TypeScript client|----+  <-----------------  +-------------------+
+-------------------+         Signed PDF

Yes. DocuSign officially retired the Signature Appliance product line on July 31, 2023. And yes, I built a cross-platform client for it in 2026. The appliance is discontinued, the docs are archived, the cipher suites are from a bygone era, and the server still happily runs on TLSv1.0 / RC4-MD5 like it's 2011. What are you going to do about it?

The Armenian Government's EKENG CoSign appliance doesn't care about DocuSign's product roadmap -- it's on-prem, it works, and thousands of documents get signed through it every day. Somebody had to write a proper cross-platform client for it. Might as well be me.

macOS

brew install lobotomoe/revenant/revenant

Linux

snap install revenant

Windows

winget install --source msstore 9NVH62M20DS3    # WinGet
scoop bucket add revenant https://github.com/lobotomoe/scoop-revenant
scoop install revenant                           # Scoop

Or download binaries from GitHub Releases.

Python (docs)

pipx install revenant    # recommended
pip install revenant     # or inside a venv

TypeScript / Node.js (docs)

npm install revenant-sign

• Embedded and detached PDF signing with customizable visual appearance
• Signature verification -- hash integrity, CMS structure, certificate chain
• PKI chain validation against ETSI Trust Service Lists (TSL)
• Localization -- English, Russian, Armenian
• Batch signing -- sign multiple files in one session
• Cross-platform GUI (tkinter) and CLI
• macOS universal binaries (arm64 + x86_64)
• Legacy TLS support -- TLS 1.0 / RC4 for servers that require it

Signed PDFs verified against third-party services that accept EKENG digital signatures:

• ekeng.am/sign_check -- EKENG signature validator
• e-request.am -- e-request.am document upload
• self-portal.taxservice.am -- Tax Service self-portal
• file-online.taxservice.am -- Tax Service online filing

Protocol, API, and server-specific docs live in docs/ and are shared between clients.

• DocuSign Signature Appliance API Guide v8.0 (PDF)
• DocuSign Signature Appliance Admin Guide v8.0 (PDF)
• OASIS DSS Standard
• EKENG CoSign page

This is an unofficial, independently developed client. It is not affiliated with, endorsed by, or supported by EKENG, ARX, or DocuSign.

• This software is provided "as is" without warranty of any kind
• Electronic signatures carry legal significance — verify that your use case complies with applicable laws and your organization's policies
• You are responsible for safeguarding your CoSign credentials and for all signatures made using this tool
• This tool communicates with CoSign servers using the documented OASIS DSS SOAP protocol — the same public API described in the official API Guide. No proprietary software is reverse-engineered or redistributed

This program does not collect, transmit, or share any data with the developer or third parties. It communicates only with the CoSign server you configure. See Privacy Policy.

Apache 2.0