I recently switched to using this for a web app from Prawn. The main app is in Ruby, but this was so much nicer (simpler API, much, much faster PDF generation)

I recently switched to using this for a web app from Prawn. The main app is in Ruby, but this was so much nicer (simpler API, much, much faster PDF generation) than Prawn for our particular use case (PDFs with lots of exact positioning of text and images) that I actually set up an entire Node server just to use PDFKit. Give it a shot if you generate a lot of PDFs.