Pivotal Web Services (PWS): All versions
You are trying to push your application and specify a specific version of the runtime or language used by your application. The application fails to stage, giving an error:
2014-09-24T12:35:02.53-0600 [STG] ERR Expected dependency to exist but could not find it: <url>
When you see the error above, it means that the particular version you have specified is unknown to the buildpack. This could be due to entering an incorrect version number or because the buildpack needs to be updated to include support for the latest version of your runtime. Most buildpacks, like the Ruby, Go or Python build packs, need to be updated to support new versions of their respective runtimes.
These updates may take a little time to become available in the default list of buildpacks on PWS. If you encounter this problem, you can often work around the issue by simply using a specific buildpack instead of relying on the default included with PWS. You can do this by adding the -b argument to your cf push command or by adding the buildpack attribute into your manifest.yml file, and indicating the URL of the buildpack you'd like to use.
Ex: command line
cf push -b https://github.com/my/buildpack
--- applications: - name: app-name memory: 128M instances: 1 path: . buildpack: https://github.com/my/buildpack
Here are links to the buildpacks supported on PWS.