This generates CUE schema from CloudFormation Resource Specification.
Specifically, it uses the cfn-python-lint extended specs (e.g. us-west-2).
You can get the latest specs by running go run . in the root of this repo. That will generate specs in pkg/github.com/TangoGroup/aws.
Another important file is pkg/github.com/TangoGroup/aws/fn/fn.cue. This defines the CloudFormation Intrinsic Functions.