Currently the Lambda is being set to run in the Node 0.10 environment. Setting the default to Node 4.3 would be preferred to take advantage of newer syntax. Having a runtime config option in the YAML file could be useful.
Unrelated, I gave this module a positive review on my blog, here: http://mark.stosberg.com/blog/tech/review-of-nodejs-lambda-serverless/
You can use Runtime param to set Node 4.3 in the yaml file.
RoleName: YOUR_LAMBDA_EXECUTION_ROLE # Role ARN will generate from RoleName automatically
I will update default params.
fixed and released new version.