There are around 10 independent PDF engines, and I built a new one from scratch.
I'm a student who mostly built little apps for myself. About 14 months ago I needed to edit a random PDF and couldn't find a good web tool that actually edits them. It made me wonder: billions of people use PDFs for work, school, and legal documents, so why can almost no web service truly edit them? So I tried to build one, and failed. I didn't understand why it was so hard. I tried combining pdf.js and jsPDF but kept hitting walls. Then it clicked: most JavaScript PDF libraries only do two thin
