I personally think both have their place, and it's partly a preference thing. Terraform is a nice constrained domain specific language, Pulumi is very expressi

I personally think both have their place, and it's partly a preference thing. Terraform is a nice constrained domain specific language, Pulumi is very expressive, but that comes with a cost. So we'll see how that comes out. However, the Pulumi AWS integration with lambda which they call Crosswalk is definitely quite magical. It provides you simple primitives and let's you create lambdas as inline JavaScript lambda expressions, handling closures and all referenced infrastructure resources. Building a small project with it which involved a few lambdas, queues, cloudwatch rules and a dynamodb table really felt like the future is here.