TinaCMS : Tina is an open-source site editing toolkit for React-based sites like Next.js & Gatsby to build content management directly into your website.
StyleDocco : StyleDocco generates documentation and style guide documents from your stylesheets.
Tracery : A story-grammar generation library for javascript. Write grammar objects, get generative stories.
TCPDF : TCPDF is a FLOSS PHP class for generating PDF documents.
SpritePad : With SpritePad you can create your CSS sprites within seconds. Simply drag & drop your images and have them immediately available as one PNG sprite + ...
A fast static site generator in a single binary with everything built-in.