rosie VS once

I think you'd be better served to try to port Rosie Pattern Language (https://gitlab.com/rosie-pattern-language/rosie) to Kotlin than to try to roll your own. There are definite corner cases in RegEx (sounds like you've already hit some) where the asympototic performance is so large that the code is practically unrunnable. Rosie addresses several of those cases.

I had to spend a lot of time clicking through links to finally find an example: https://gitlab.com/rosie-pattern-language/rosie/blob/master/rpl/date.rpl

Something could be based on the "Rosie Pattern Language"[0]. There is already a parser for en_US/en_EU dates[1], which should be simple to extend to date ranges.

[0]: https://gitlab.com/rosie-pattern-language/rosie/-/blob/maste...

[1]: https://gitlab.com/rosie-pattern-language/rosie/blob/master/...

Maybe something like Rosie?

I have written something [once] that de-dupes on just the URLs, you could take this way further with images and content analysis.

This is also manly an app to stop me from scrolling across the same stories on HN and lobste.rs again and again multiple times a day. So it lacks reddit specific features.

[once] https://github.com/batram/once