Signature PDF

Signature PDF is an open-source, self-hosted web application used for signing and managing PDF documents. It provides a browser-based interface for users to apply signatures, modify document structures, and adjust file properties. The application serves as a centralized tool for handling common document tasks without requiring local software installations on client machines.

The application is deployed as a server-side tool utilizing a PHP backend. It supports both individual signing and a multi-signature mode that allows several people to sign a single document. Users interact with the software through a web browser to upload, edit, and download their files, making it accessible across different operating systems and devices.

Key features

• Digital signing of documents alone or with multiple participants
• PDF organization including merging, sorting, rotating, and deleting pages
• Extraction of specific pages from existing PDF files
• Editing of PDF metadata with customizable default fields
• Compression of PDF files to reduce file size
• Encrypted server-side storage for PDFs using GPG
• Digital signature verification using poppler-utils and libnss3-tools

The software is built using the Fat-Free PHP micro framework and integrates a wide array of libraries for document processing, including PDFtk, Ghostscript, and PDF.js. For multi-signature workflows, the application can be configured to store files on the server with optional symmetric encryption to ensure that only authorized signers can access the content. This architecture allows administrators to manage how documents are stored and accessed on their own infrastructure.

Administrators have several configuration options to tailor the application to their needs. They can define custom retention periods for shared PDFs, ranging from one hour to one year, to automate the cleanup of old documents. The interface can be further modified through a custom CSS file, and the metadata editor can be pre-loaded with specific HTML input types such as text, date, number, or email to standardize data entry for different document types.

Signature PDF is a utility for users and organizations seeking a self-hosted solution for basic PDF manipulation and electronic signatures.