I see you’re using strings. You can do that, but then you’ll lose control over formatting, and additional context info that might be contained in them.

I just haven't figured out how to jam multiple error types into one enum variant yet. There's no reason for the consumer of the module to get more pointless variants, so I'm not really sure I want an enum of enums, but maybe I'm overthinking it. I'll fiddle more and check out your link later today.