Nonetheless I believe this is completely feasible.
Two possible approaches :
1. We'd need to build a program that would query relay(s) to get the events/notes published by one or multiple npubs and then generate the RSS XML files that then would be distributed by a webserver
2. A program that would be the webserver itself and that would request the relay when a URL is called to generate the XML content on the go
Second option would be the one I'd prefer
the first approach is like using this client https://snowcait.github.io/nostr-playground/ input a relay and get events and
than produce the rss feed somehow, the second approach is a relay itself?
Nope. The main difference is that option 1 would write rss XML files whilst option 2 would generate the RSS XML as a buffered content on the go to serve it.
In no case the app would be a relay itself and I'm not sure it would be a good option. I'd keep the relay as a separated app
The playground can be helpful I guess to check the data structure you're likely to receive and prepare an implementation of your feature ( transforming the raw data to some RSS XML content )
my pretty poor attempt 😔 it's a manual thing https://nostrools.netlify.app/nostrools
It seems nice solution
