The .net core configuration mechanism has a hierarchy of providers it reads from, one of which is environment variables, and strongly typed configuration is supported out of the box, so you're exact use case is supported natively by it.
This blog has similar thoughts: https://rimdev.io/strongly-typed-configuration-settings-in-a...
or this blog: https://adamstorr.azurewebsites.net/blog/beyond-basics-aspne...
Or simply google 'asp net strongly typed configuration' and notice everyone seems to be reaching similar conclusions and building their own things.
Just load the setting yourself and register it as a singleton.
Meh, seems like just an interface to me.
Yes, indeed you have. I've tried to both skim and read the "introductory" documentation for `Options<T>` and the only gain I could figure out is monitoring + refresh. I still have no idea how to use it though, so I don't.