diff --git a/docker-bake.hcl b/docker-bake.hcl
index 6265fd20..c446f75b 100644
--- a/docker-bake.hcl
+++ b/docker-bake.hcl
@@ -103,7 +103,7 @@ variable "ALFRESCO_REPO_USER_NAME" {
 }
 
 variable "TARGET_ARCH" {
-  default = [""] # e.g. ["linux/amd64"]
+  default = "" # e.g. ["linux/amd64"]
 }
 
 target "java_base" {