When that happens for me in Ansible I just drop into Python and write a custom module. They're pretty straightforward.

The benefit with Chef is that it is always Ruby. There is no dropping in/out of anything other than Ruby. As a Ruby programmer I quite like that. It doesn't fight the language it is embedded in and uses all the language idioms to great effect.

How are you building your AMIs?

We're using Ansible and building the AMIs on a dedicated ec2 instance (started for a build and shut down afterwards). The AMIs are fully baked and environment information is configured via user_data in the launch configuration.

We use SSH to communicate with the build instance as a result, but I'd rather spend time during the build than during start-up of a new instance.

Not the person you asked the question of, but we’re building AMIs (and VMware images) using packer.io (via the masterless puppet provisioner). It works nicely and with a minimum of fuss.