This buildpack is no longer required and is unsupported as its functionality has been built directly into the Heroku app-setups API.
This is a Heroku buildpack that installs a small tool for waiting on Postgres and Redis addons to become available.
The tool itself is available at heroku/addon-wait.
You need to add this buildpack to your list of buildpacks:
$ heroku buildpacks:add https://github.com/heroku/heroku-buildpack-addon-wait.git
Then you can add
bin/addon-wait as post deploy script to your
app.json, see here for details.
Copy the snippet above into CLI.