A “reply guy” (wikipedia) is someone who responds to posts/comments in an annoying (usually smug/condescending) way, like what you think of when you think of a “redditor”. Big platforms like Reddit like reply-guys because they generate engagement (often someone telling the reply-guy to f-off) it’s also not a behavior that an algorithm can recognize, so human mods/admins are needed to curb it.
Over time, if Reply-guys are not banned they tend to make the overall ecosystem too exhausting to participate in, and (authentic, desireable) engagement declines.
How does it work self hosting? Is it querying other search engines or just maintaining a database on your server?