I've uploaded Ponychan's source code to a Git repo here
. Going into detail on how to use git would be too much work, and there are tutorials all over the internet on how to use it so I'm not going to explain that. If you're a developer you should already have a decent idea on how to use it, and if you don't, there's no time like the present to learn. The README file, which is displayed on the repo's main page explains how to actually install the source code in a VM for editing.