This is an extremely minimalistic web forum engine based on D3 and SQLite. Includes a backend and a servicable (albeit not feature-complete) markdown renderer.
Originally written as a low-stakes experiment to see if D3 is usable as a general DOM manipulation library for an SPA, and to see if I could build a reasonable single page app while also deliberately eschewing every UI programming design pattern I've ever heard of.
It was in use for some time by a small community that has since moved on. While I consider it to be a successful proof of concept, I don't advise actually using it, so installation instructions are not included.