Rust's built-in lints are configurable with compiler directives, so you'll be able to add #![deny(bare_trait_objects)] To the top of your crate and cause

Rust's built-in lints are configurable with compiler directives, so you'll be able to add #![deny(bare_trait_objects)] To the top of your crate and cause a compiler warning if someone uses the old syntax on your project. EDIT: just realized I mis-parsed "you" in parent. Oh well.