Why am I seeing "heroku-cli: This CLI is deprecated. Please reinstall" after installing the Heroku CLI?

Resolution

Seeing deprecation warnings means you probably have an older install of the heroku program in your $PATH. You can check the current heroku binary from the output of the following command, when run on your (Linux or Mac) machine:

which heroku

Two possibilities are an older install via homebrew (OSX users only) or an older version of the heroku Ruby gem. You should be able to remove those with either:

brew uninstall heroku

or

gem uninstall heroku --all