I finally wrapped up some (minor) work around #palaver. This one add human-friendly slugs to categories and threads.
https://github.com/katafrakt/palaver/pull/10
I went in a really wrong alleys with that before, trying to add slugger as a provider, not just a dependency. Finally, I ended up creating it as just a "regular" dependency in one of the slices, as it won't probably be needed elsewhere.
The main challenge was to isolate Stringex, which is very slow to load, in tests.