It doesn't do anything else, so to actually compile your app you should use heroku-buildpack-multi to combine it with a real buildpack.
To use this buildpack, you should prepare .buildpacks file that contains this buildpack url and your real buildpack url.
$ ls .buildpacks ... $ cat .buildpacks https://github.com/guilherme-otran/heroku-buildpack-ffprobe $ heroku create --buildpack https://github.com/ddollar/heroku-buildpack-multi $ git push heroku master ...
You can verify installing ffmpeg by following command.
$ heroku run "ffprobe"
Copy the snippet above into CLI.