provider "do" { api_key = "${var.foo}" } data "do" "depends" { depends_on = ["data.do.simple"] } resource "aws_security_group" "firewall" { count = 5 } resource aws_instance "web" { ami = "${var.foo}" security_groups = [ "foo", "${aws_security_group.firewall.foo}" ] network_interface { device_index = 0 description = "Main network interface" } }