NOTE WARNING DANGER ETC: You have to give heroku (via environment variables) your public and private github deploy key for the repository you're deploying. Make sure you understand that this means that heroku (themselves, or if their data is stolen) could access your github repo. OK? Proceed!
Copy the git-across.sh file to the root of your hubot. Copy github-to-heroku.coffee to your scripts folder in your hubot.
Generate a key with ssh-keygen. Dont set a passphrase.
Upload it to github under your project's Deploy Key field.
We'll call this my-github-deploy-ssh-key from now on.
Send the public key to heroku:
heroku keys:add my-github-deploy-ssh-key.pub
Export the following config vars to heroku:
GITHUB_KEY="`cat my-github-deploy-ssh-key`"
GITHUB_PUBLIC_KEY="`cat my-github-deploy-ssh-key.pub`"
GITHUB_URL="git@github.com:myproject/myrepo.git"
HEROKU_GIT_URL="git@heroku.com:myherokurepo.git"
Commit the script changes to your hubot and push him to heroku. Then, in campfire:
hubot deploy
Tada!