A command-line tool mdgen v0.9.0 is now available. mdgen can be used to generate HTML docs, diagram images (PNG, SVG), PDF documents, and template-based custom codes. Now you can automate generation of codes and artifacts from your model files (.mdj) in your build scripts. Or, if you are familiar with Node.js, then you can write your own scripts using metadata-json library.
For more information: https://github.com/staruml/mdgen