On Google+ we used Circles for these, where you posted specific content to your Lninx circle. Only people that you followed and added to your Linux circle could see it. This worked well for a while, but eventually it seemed apparent that the fire hose method worked better. Then later we pivoted to Communities, and they seemed to work great for specific content. We have Communities here now on Nostr. Go post to /n/Linux or make your own!
Discussion
I don’t really want to post in a community though. I just want a small categorized feed of linux things im doing that people can choose to subscribe to or ignore without polluting my main feed
Your own Linux community is essentially what you're describing though. Aren't the results the same? It's yours. You control the content that goes into it. People can choose to follow or join your community. You could even add a posting feature on Damus that allows you to post to your profile or a specific community from a list of your communities. This is how it worked on G+.