In our project coq-of-rust we translate programs written in Rust to equivalent programs in the language of the proof system Coq 🐓, which will later allow us to formally verify them. Both Coq and Rust have many unique features, and there are many differences between them, so in the process of translation we need to treat the case of each language construction separately. In this post, we discuss how we translate the most complicated one: traits.
To formally verify Rust programs, we are building coq-of-rust, a translator from Rust 🦀 code to the proof system Coq 🐓. We generate Coq code that is as similar as possible to the original Rust code, so that the user can easily understand the generated code and write proofs about it. In this blog post, we explain how we are representing side effects in Coq.
Our primary goal at Formal Land 🌲 is to make Tezos the first crypto-currency with a formally verified implementation. With formal verification, thanks to mathematical methods, we can check that a program behaves as expected for all possible inputs. Formal verification goes beyond what testing can do, as testing can only handle a finite amount of cases. That is critical as cryptocurrencies hold a large amount of money (around $3B for Tezos today). The current result of our verification project is available on nomadic-labs.gitlab.io/coq-tezos-of-ocaml. Formal verification is also key to allowing Tezos to evolve constantly in a safe and backward compatible manner.