[ikawe]

For me, when something is merged into master, that means that it is immediately destined for deployment.

so instead of

    git co master
    git merge --no-ff feature/my_feature
    git push github
    git push heroku

Just becomes

    git co master
    git merge --no-ff feature/my_feature
    git push github

Just saving a step. And also saving the confusion that happens when something is in master and not deployed because someone got distracted.

Also, you could deploy to heroku as the result of merging a pull request through the github web-ui (if you're into that kind of thing).