but stability isn’t something that would drive a gentoo user away either.
a lot of the draw of gentoo from what I saw was being able to configure everything down to how it gets compiled. it’s simple to apply a patch to a package before it gets built or maintain a custom kernel config in nixos, as well as all the advantages of declarative os
it’s not data validation like you’d put in a dto, it’s an assertion library for unit tests and such. It’s mostly just sugar that makes chaining together assertions more concise with better autocomplete you get from fluent apis. You can do the same thing with built in Assert but it’s nowhere near as nice to use