diff --git a/main.tf b/main.tf
index 0e4a135..673e093 100644
--- a/main.tf
+++ b/main.tf
@@ -1,4 +1,9 @@
 locals {
+  module_versions = {
+    backend_bucket      = "v1.3.0",
+    backend_serverless  = "v1.2.0",
+    gcp_serverless_negs = "v1.0.1"
+  }
   cloud_run_backends = {
     for service in keys(var.services) : service => module.serverless_negs[service].backend
   }
@@ -41,7 +46,7 @@ data "google_certificate_manager_certificate_map" "default" {
 # Backend Serverless Network Endpoint Groups
 module "serverless_negs" {
   for_each                             = var.services
-  source                               = "github.com/brandlive1941/terraform-module-backend-serverless?ref=v1.2.0"
+  source                               = "github.com/brandlive1941/terraform-module-backend-serverless?ref=${local.module_versions.backend_serverless}"
   project_id                           = var.project_id
   name                                 = coalesce(each.value.backend["name"], each.key)
   cloud_run_services                   = each.value["cloud_run_regions"]
@@ -55,7 +60,7 @@ module "serverless_negs" {
 # Backend Bucket Services
 module "buckets" {
   for_each                             = var.buckets
-  source                               = "github.com/brandlive1941/terraform-module-backend-bucket?ref=v1.2.0"
+  source                               = "github.com/brandlive1941/terraform-module-backend-bucket?ref=${local.module_versions.backend_bucket}"
   project_id                           = var.project_id
   name                                 = each.value["name"]
   location                             = each.value["location"]
@@ -72,7 +77,7 @@ module "buckets" {
 
 # Load Balancer
 module "lb" {
-  source                = "github.com/brandlive1941/terraform-module-gcp-serverless-negs?ref=v1.0.1"
+  source                = "github.com/brandlive1941/terraform-module-gcp-serverless-negs?ref=${local.module_versions.gcp_serverless_negs}"
   project               = var.project_id
   name                  = var.name_prefix
   address               = data.google_compute_global_address.default.address