>>11
"Less than 3500 lines" is significant because that is a fully featured imageboard. It has captcha, tripcodes, file uploads (epub, pdf, mp4, etc.), image thumbnails, web interface for administration/moderation, transparent moderator action logging, moderator permission levels, sticky threads, thread locking, file uploads, etc. Everything is done without JavaScript. If you don't need the extra features, just strip them out of the source code.