diff --git a/.circleci/config.yml b/.circleci/config.yml
new file mode 100644
index 000000000..e14c1cdc8
--- /dev/null
+++ b/.circleci/config.yml
@@ -0,0 +1,24 @@
+# Golang CircleCI 2.0 configuration file
+#
+# Check https://circleci.com/docs/2.0/language-go/ for more details
+version: 2
+jobs:
+  build:
+    docker:
+      # specify the version
+      - image: circleci/golang:1.11
+
+      # CircleCI maintains a library of pre-built images
+      # documented at https://circleci.com/docs/2.0/circleci-images/
+
+    #### TEMPLATE_NOTE: go expects specific checkout path representing url
+    #### expecting it in the form of
+    ####   /go/src/github.com/circleci/go-tool
+    ####   /go/src/bitbucket.org/circleci/go-tool
+    working_directory: /go/src/github.com/hashicorp/packer
+    steps:
+      - checkout
+
+      # specify any bash command here prefixed with `run: `
+      - run: pwd
+      - run: make ci
\ No newline at end of file
diff --git a/website/source/docs/templates/user-variables.html.md b/website/source/docs/templates/user-variables.html.md
index 09222eb35..0247b666f 100644
--- a/website/source/docs/templates/user-variables.html.md
+++ b/website/source/docs/templates/user-variables.html.md
@@ -24,10 +24,13 @@ configuration templates work yet, please read that page first.
 
 ## Usage
 
-User variables must first be defined in a `variables` section within your
-template. Even if you want a user variable to default to an empty string, it
-must be defined. This explicitness helps reduce the time it takes for newcomers
-to understand what can be modified using variables in your template.
+In order to set a user variable, you must define it either within the
+`variables` section within your template, or using the command-line `-var` or
+`-var-file` flags.
+
+Even if you want a user variable to default to an empty string, it is best to
+explicitly define it. This explicitness helps reduce the time it takes for
+newcomers to understand what can be modified using variables in your template.
 
 The `variables` section is a key/value mapping of the user variable name to a
 default value. A default value can be the empty string. An example is shown