Cyrus Works is a domain redirection to the Cyrus IMAP project's Travis CI dashboard.
Whenever the Cyrus team push changes to the project repository, Travis CI (via github integration) automatically builds the new commits. This also applies to pull requests submitted through the GitHub site.
Cassandane, the Cyrus IMAP test framework gets pulled in to the Docker Container, confirms existing functionality still works and no regression bugs have been introduced.