diff --git a/README.md b/README.md
index af67aa2..a5f8347 100644
--- a/README.md
+++ b/README.md
@@ -57,6 +57,7 @@ module "localhost_function" {
 | bucket\_force\_destroy | When deleting the GCS bucket containing the cloud function, delete all objects in the bucket first. | `bool` | `false` | no |
 | bucket\_labels | A set of key/value label pairs to assign to the function source archive bucket. | `map(string)` | `{}` | no |
 | bucket\_name | The name to apply to the bucket. Will default to a string of the function name. | `string` | `""` | no |
+| build\_environment\_variables | A set of key/value environment variable pairs available during build time. | `map(string)` | `{}` | no |
 | create\_bucket | Whether to create a new bucket or use an existing one. If false, `bucket_name` should reference the name of the alternate bucket to use. | `bool` | `true` | no |
 | description | The description of the function. | `string` | `"Processes events."` | no |
 | entry\_point | The name of a method in the function source which will be invoked when the function is executed. | `string` | n/a | yes |
diff --git a/main.tf b/main.tf
index 818805d..b06786e 100644
--- a/main.tf
+++ b/main.tf
@@ -130,12 +130,13 @@ resource "google_cloudfunctions_function" "main" {
     }
   }
 
-  labels                = var.labels
-  runtime               = var.runtime
-  environment_variables = var.environment_variables
-  source_archive_bucket = var.create_bucket ? google_storage_bucket.main[0].name : var.bucket_name
-  source_archive_object = google_storage_bucket_object.main.name
-  project               = var.project_id
-  region                = var.region
-  service_account_email = var.service_account_email
+  labels                      = var.labels
+  runtime                     = var.runtime
+  environment_variables       = var.environment_variables
+  source_archive_bucket       = var.create_bucket ? google_storage_bucket.main[0].name : var.bucket_name
+  source_archive_object       = google_storage_bucket_object.main.name
+  project                     = var.project_id
+  region                      = var.region
+  service_account_email       = var.service_account_email
+  build_environment_variables = var.build_environment_variables
 }
diff --git a/variables.tf b/variables.tf
index 2542ff2..8ae5135 100644
--- a/variables.tf
+++ b/variables.tf
@@ -178,3 +178,9 @@ variable "log_object_prefix" {
   default     = null
   description = "Log object prefix"
 }
+
+variable "build_environment_variables" {
+  type        = map(string)
+  default     = {}
+  description = "A set of key/value environment variable pairs available during build time."
+}