diff --git a/webtrees/Dockerfile b/webtrees/Dockerfile
index eae8e41bb..32d6d75c8 100644
--- a/webtrees/Dockerfile
+++ b/webtrees/Dockerfile
@@ -14,7 +14,8 @@
 #################
 
 ARG BUILD_VERSION
-FROM nathanvaughn/webtrees:latest-alpha
+ARG BUILD_UPSTREAM="2.1.0-alpha.1"
+FROM nathanvaughn/webtrees:$BUILD_UPSTREAM
 
 ##################
 # 2 Modify Image #