NPW, or Nyctergatis PDF Writer, is an open-source ISO-C library for the creation of PDF documents.

NPW's goal is simplicity and small size, not a full implementation of PDF. It has the following features:

- less than 30 KB for core functions
- multiple-page documents
- vector graphics
- text with the 14 standard PDF fonts
- PDF metadata
- paragraph layout with multiple fonts
- simple markup for text style