I know there exists a plugin for nginx to load the config through perl. I was wondering, does anyone have any experience doing this without using a plugin? Possibly a fuse-backed Python script that queries a DB?
I would really like to not use the perl plugin, as it doesn't seem that stable.
I haven't seen any working solution to solve your task, a quick google search doesn't give any useful information either (it doesn't look like HttpPerlModule could help with DB stored configuration). 
It sounds like it's a good task to develop and contribute to Nginx project !
Running Nginx with a database-backed config file