Indigo PDF relies on several key technologies:

Java: We use the JAVA framework to host the WebUI, and within it, we incorporate Spring Boot, Thymeleaf, and PDFBox. Apache PDFBox, a fundamental component, forms the core of the PDF editing capabilities in Indigo-PDF.

JavaScript: We leverage various JavaScript libraries, including PDF.js and PDF-LIB.js, to enhance our PDF processing functionalities.

Additionally, we integrate other open-source applications alongside our own to expand our feature set:

• LibreOffice: This tool is employed for document conversions.
• OcrMyPdf: It is used for Optical Character Recognition (OCR) to transform PDF images into text.
• GhostScript: Bundled with OCRmyPDF, GhostScript plays a role in compressing PDF documents, contributing to the overall functionality of Indigo PDF.