I wonder if this shouldn't be on the "rust" side, rather than on the "crates.io"-side. Considering[1], I think I'd prefer either/or:

    extern unsafe crate phrases; // It's all UNSAFE!

Or: extern crate phrases; // It's mostly safe

    use unsafe phrases::english; // But not English

The idea being, that either phrases wouldn't be imported/give an error -- or everything in phrases except "english" would be imported -- and english would only be imported if qualified with "unsafe".

Either way... I can see this going the way of try/catch/throws in java -- where the usefulness diminishes as lazy programmers (we're all lazy) end up polluting everything with unsafe (just like "throws Exception e..").

[1] https://doc.rust-lang.org/book/crates-and-modules.html