Pdf-sign

Judgement

What it is

Developer tool

What it does

A Python tool for placing visible signature images onto PDF files, mainly for Linux users.

Adopt it when

You need to stamp a handwritten-style signature onto a PDF without a commercial app.

Watch out

It adds visual signatures only, not cryptographic ones.

Ready for

Usable

Runs as

Command line

Built with

Python

How established

Established: started 5 years ago, no tagged release yet.

What the license allows

You can build it into a product you sell, as long as you keep its copyright notice.

Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: Pdf-sign → CPython → GCC → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

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Commercial document signing libraries and signing servers

1. 1
   iText DITO and pdfSign Apryse

   The leading Java and C# PDF Library SDK. A programmable Java and .NET PDF SDK library to create, manipulate and edit PDF documents. Convert Html files to pdf, Debug pdf files, extract data from PDF and more.

   Building block Production-ready A Java or .NET application needs to generate or digitally sign PDFs in-process with mature tooling.

   Commercial
2. 2
   Apryse SDK Apryse

   Integrate document processing capabilities into any software applications. Generate, convert, view, edit, and sign pdf and documents easily.

   Building block Production-ready Your product needs a full in-app document viewer and editor and you can pay for a commercial SDK.

   Commercial