This is a Heroku buildpack for using audiowaveform and lame in your project.
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.
Shamelessly forked from the ffmpeg heroku buildpack by Shunji Konishi.
To use this buildpack, you should prepare a .buildpacks file that contains this buildpack url and your real buildpack url:
$ ls
.buildpacks
...
$ cat .buildpacks
https://github.com/lepinsk/heroku-buildpack-audiowaveform
$ heroku create --buildpack https://github.com/ddollar/heroku-buildpack-multi
$ git push heroku master
...
You can verify that sox is installed by calling:
$ heroku run "audiowaveform"