You already have Berkshelf and Packer installed, right? Nice.
Make sure you have the AWS CLI installed and configured.
Might be nice to provide this implementation via a CloudFormation template and then have it do the rest to generate the AMI and put the AMI in the CFN Outputs since this is the end result the user is seeking.
The README states:
Might be nice to provide this implementation via a CloudFormation template and then have it do the rest to generate the AMI and put the AMI in the CFN Outputs since this is the end result the user is seeking.