You can define tests using ert, then use a bash script to load the module and run the tests. Examples:

• emacs-module-rs's own tests and script.
• magit-libgit2's tests and script.

Continuous testing during development can be done using cargo-watch:

cargo watch -x 'build --all' -s bin/test.sh

A future version will have tighter integration with either cargo or Cask.