diff --git a/config.go b/config.go
index <HASH>..<HASH> 100644
--- a/config.go
+++ b/config.go
@@ -23,6 +23,7 @@ const defaultConfig = `
 		"amazon-chroot": "packer-builder-amazon-chroot",
 		"amazon-instance": "packer-builder-amazon-instance",
 		"digitalocean": "packer-builder-digitalocean",
+		"docker": "packer-builder-docker",
 		"openstack": "packer-builder-openstack",
 		"qemu": "packer-builder-qemu",
 		"virtualbox": "packer-builder-virtualbox",
main: Default config has docker