The biggest thing I've noticed is that terraform doesn't, out of the box, have any way of bringing in your existing resources, and sharing the [tfstate file] that has the current state of your world is its own challenge. The ec2 module of ansible has `count_tag`, and that was exactly what I wanted: "I want this many boxes that are identified by these tags."

Played with an external tool call [terraforming] that creates a terraform setup from your existing boxes, but that, too, was way more than I wanted.

Terraform is a very neat tool, but learning the AWS ecosystem _and_ this third-party tool that has its own very strong set of best practices was too much for me. If you're experienced, and especially if you're already using CloudFormation heavily, you can probably get a lot of mileage out of terraform.

Doing a quick search to make sure I'm not crazy, it looks like terraform 0.7 will start to support importing, so that's something: https://github.com/hashicorp/terraform/issues/581

[tfstate file]: https://www.terraform.io/docs/state/remote

[terraforming]: https://github.com/dtan4/terraforming