diff --git a/modules/create-rds-postgres-tester/main.tf b/modules/create-rds-postgres-tester/main.tf
index ef8a7a48..bc09d488 100644
--- a/modules/create-rds-postgres-tester/main.tf
+++ b/modules/create-rds-postgres-tester/main.tf
@@ -78,7 +78,7 @@ resource "aws_s3_object" "dependencies" {
   key    = "create_rds_postgres_tester.zip_dependencies.zip"
   source = data.archive_file.dependencies.output_path
 
-  etag = data.archive_file.dependencies
+  etag = data.archive_file.dependencies.output_md5
 }
 
 resource "aws_lambda_layer_version" "dependencies" {