Inspired by a Rust utility I saw posted the other day: https://www.reddit.com/r/rust/comments/13gujgg/todo_by_compiletime_lifetimes_for_comments/

I don't know anything about Rust, but I've recently dived into attributes in .NET and figured I could probably recreate the experience in .NET:

Behold: https://imgur.com/a/SR28yPc

Behind the scenes, the code grabs the method that triggered enforcement (this method can be called anywhere in the code base, does not need to be called by a method decorated with an attribute), looks up the associated assembly, loops over all available methods marked with a specific attribute, then evaluates each attribute and throws an exception if the evaluation fails (a date or version number has elapsed, for example). I know that's not super-performant, but the idea would be enforcement would be a one-time check in the entrypoint to a program.