Indeed, the package size increases by 3MB with the `groovy-all` dependency.

It’s clearly not required for basic Lambda function where pure Java will do the job. For more complex lambda functions, Groovy adds some nice syntactic sugar and removes some Java verbosity. It’s up to you to decide the additional cost in package size.

At AgoraPulse, most of our codebase is written in Groovy (based on Grails framework), because we really enjoy the coding experience and agility that the language provides. That’s why we stick with it.

In a few weeks, we are going to push our first Groovy-based Lambda to production: an AWS DynamoDB event processor to index data in AWS CloudSearch.

In 2017, we plan to move more services to AWS Lambda.

So more real feedback from the ground pretty soon :)!