I wrote a draft novel for Nanowrimo this year and short circuited a lot of the world-building by setting it up the road from where my current campaign is set.
This had one or two neat pieces to it because it was easy to have the characters rattle on about their concerns and what was happening in the background because all that was already in play, I knew what was going on.
What was super useful, that I did not expect, was setting out the layout of the city where a lot of the action took place was greatly simplified by using some of the quick and easy world-building tools that are sloshing around in the OSR scene at the moment. In particular, I pulled up the glorious In Corpathium city generator to quickly block out where things were and what was happening in the various places.
