[jfrunyon]

> E.g. I could compare the origin IP, determine the country, and change the response based on that. And there are plenty of use cases like this which you cannot express in a config language.

Well, you can do that in plenty of "config languages", including nginx[1]. The reason Lambda exists is that it's good for Amazon, because they can push all the costs of the logic back onto the customer. (It could also be good for the customer, in that whatever configuration Amazon might otherwise support could be limited.)

[1] http://nginx.org/en/docs/http/ngx_http_geoip_module.html