Show HN: PDF Assembler – client-side PDF editing Here's a neat hack I made recently to do basic PDF editing directly in a browser—without having to upload anything to a server. I was initially looking for a way to do simple PDF modification (extracting pages, merging, and adding page numbers). There are some good server-side tools for this (QPDF, PDFTk, PDFBox, iText, Hummus), but for better speed and privacy I really wanted a 100% client-side solution. There are a few good JavaScript PDF libraries for reading and displaying PDFs (pdf.js) and creating PDFs from scratch (jsPDF, PDFKit), but I couldn't find any for editing existing PDFs. So, I did what any self-respecting hacker would do, and rolled my own. :-) Actually, I found out that Mozilla's pdf.js solved half the problem, as it does an excellent job disassembling PDF files. So all I had to do was figure out a way to put them back together again. The result is PDF Assembler, now available on GitHub and NPM. I also put t...