diff --git a/README.md b/README.md
index fd20c8c..f2eb424 100644
--- a/README.md
+++ b/README.md
@@ -52,6 +52,7 @@ module "digitalocean_spoke" {
 
 | Name | Version |
 |------|---------|
+| terraform | >= 0.13 |
 | digitalocean | >= 1.22 |
 
 ## Providers
diff --git a/main.tf b/main.tf
index 528add8..dda92e7 100644
--- a/main.tf
+++ b/main.tf
@@ -52,7 +52,16 @@
 
 terraform {
   required_providers {
-    digitalocean = ">= 1.22"
+    digitalocean = {
+      source  = "terraform-providers/digitalocean"
+      version = ">= 1.22"
+    }
+    null = {
+      source = "hashicorp/null"
+    }
+    random = {
+      source = "hashicorp/random"
+    }
   }
 }
 
diff --git a/versions.tf b/versions.tf
new file mode 100644
index 0000000..6b6318d
--- /dev/null
+++ b/versions.tf
@@ -0,0 +1,3 @@
+terraform {
+  required_version = ">= 0.13"
+}