diff --git a/Makefile b/Makefile
index bac4c7d..a48decf 100644
--- a/Makefile
+++ b/Makefile
@@ -5,8 +5,8 @@ CONTAINER_RUNTIME?=$(shell which podman)
 
 # CONTAINER_IMAGE
 # Defines the name of the new container to be built using several variables.
-BUILD_IMAGE_REGISTRY_HOST:=git.cryptic.systems
-BUILD_IMAGE_REGISTRY_USER:=volker.raschek
+BUILD_IMAGE_REGISTRY_HOST?=git.cryptic.systems
+BUILD_IMAGE_REGISTRY_USER?=volker.raschek
 BUILD_IMAGE_NAMESPACE?=${BUILD_IMAGE_REGISTRY_USER}
 BUILD_IMAGE_REPOSITORY:=ansible-archlinux
 BUILD_IMAGE_VERSION?=latest