diff --git a/Dockerfile b/Dockerfile
index 021d5d5..73a18e6 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,7 @@
 # https://hub.docker.com/_/monica
-FROM monica:$GIT_TAG
+# Default to 'latest' if GIT_TAG is not provided
+ARG GIT_TAG=latest
+FROM monica:${GIT_TAG}
 
 RUN \
   # Use the default production configuration