The Coherent PDF Command Line Toolkit provide a robust, professional set of tools for manipulating PDF files. The operations it offers includes split and merge, linearize, encrypt, scale, rotate, crop, bookmark, stamp, watermark, annotate, attach, and much more. It's based on the camlpdf library.
A seed project that combines Play Framework, AngularJS, Bootstrap, and MongoDB..
An FFmpeg and SoX based EBU R128 compliant loudness scanner for audio files.