I'm currently adding Rust support to MailChecker thus I had to run the Rust generated project tests on CircleCI. At the time of writing, CircleCI does not support Rust and Rustup setup had an issue with CircleCI. I just wanted to find the easiest way to use cargo test in the CI and the good news is: that's what Docker is good at!

Just add a single line to your circle.yml file and you are good to go, I hope this will help others!