is there a jobboard in civiCRM
There is no 'job board' feature as such. You could have a look at CiviHR but I don't recall it being a place where people could advertise their own jobs.

If I had to do this, on Drupal, I would be using Drupal Webforms that would generate Activities which would then be displayed in a Drupal View with links that would take the 'applicant' to another Drupal Webform where they would generate another Activity that was somehow referencing the 'job position'.

Not much help to you directly but hope this gets the conversation started.