The universal markup converter
A Privacy First PDF Toolkit
A PDF processor written in Go
PDFCraft is a free, privacy-focused PDF toolkit
MD/.JSON Document OCR and structured data extraction API
PDF transformation/manipulation program + library
a graphical user interface for the PDF Toolkit (PDFtk)
Here are my python scripts written until now
Fast, Nimble PDF Writer for Ruby
Merge images and PDFs to a single PDF
Manage your collection of PDF files
A Node queue API for generating PDFs using headless Chrome