RSS tool to remix feeds, build from webpages, and skip podcast reruns

It's been nice seeing some RSS projects pop up lately, so here's mine and the scope creep that led to it.

I wanted to read a couple feeds from their beginnings, something RSS doesn't particularly do and nobody particularly uses it for. But I've done the keep-a-tab-open-for-8-months thing more than once to work through an archive, and I don't fancy doing it again. As I worked through the steps and showed it to friends, we accumulated some other quality-of-life use cases that fit well enough into "just filter some XML" that they glommed on.

So, Sponder can:

- Run basic filtering on RSS feeds, either by keywords or regular expressions.

- Parse any webpage into an RSS feed, including autodetection of title/image/link/etc elements, following page links back through history, and coming back for new items later.

- Control the pace of that full historical feed to serve you an article per week, or 12 per day, whatever pace you like.

- Automatically detect and filter rerun episodes from a podcast feed.

- Be configured either by UI or typing some YAML.

It does not:

- Replace your RSS or podcast client, it's middleware that publishes a modified feed for you.

- Replace every one of your feeds, just the ones you wish were different. Though you can important and export OPMLs if you wish a lot were different.

- Run content through LLMs, though I'm considering it for rerun detection since metadata similarity only gets so far.

I'd love to hear from you fine folks:

- What bugs you about your feeds

- How configuring a flow goes