AWS Code Deploy

Deployments
1

I am getting the following error when building:

code-deploy-error.png1235×257 40.1 KB

My circle.yml file is:

machine:
  ruby:
    version: ruby-2.2.3
deployment:
  staging:
    branch: master
    codedeploy:
      nupack-4.2:
        application_root: /
        region: us-west-2
        revision_location:
          revision_type: S3
          s3_location:
            bucket: bucket-name
            key_pattern: nupack-4.2-{BRANCH}-{SHORT_COMMIT}
        deployment_group: deployment-group-name

Does anyone have any idea what might be going on?