This plugin integrates Darcs version control system to Jenkins. The plugin requires the Darcs binary (darcs) to be installed on the target machine.
With this plugin, you can designate a Darcs repository as the "upstream" repository. Every build will then run "darcs pull" to bring the tip of this upstream repository. In a similar manner, polling will check if the upstream repository contains any new changes, and use that as the triggering condition of the new build.