The various contract proposals for Rust are used as input to both formal verification tools as well as input to the optimizer. A good example of one such too

The various contract proposals for Rust are used as input to both formal verification tools as well as input to the optimizer. A good example of one such tool that could utilize contracts is cargo-anneal (https://crates.io/crates/cargo-anneal https://crates.io/crates/cargo-anneal)