The startup script of a Dancer application (bin/app.pl) can be used as a PSGI file. With that in mind, I was able to take the good work of Miyagawa's Heroku buildpack for general PSGI apps and hack it a little bit to use Dancer's, specifically.
via axiombox.com
David Moreno wrote a tutorial on how to deploy Dancer PSGI app on Heroku using hacked version of my buildpack.
Note that you can just write app.psgi that calls out bin/app.pl and use my buildpack as is, and that makes your Dancer app deployable on other PaaS such as DotCloud and Stackato as well.