Terrafirm isn't provider neutral. It is just a declarative wrapper for cloud provider APIs. Code using one provider is not easily translated to another.

I do think it's an excellent configuration management and provisioning tool, but Go Cloud solves a different problem.

A frustrating choice. I spend a few minutes per week running Terraform on a recent laptop. If it were written in Python, it might use more memory and require a few dependencies (which I don't care about at all) but then I could write plugins without having to deal with IPC and weird language-specific serialization (which Java should have convinced us is a bad idea).