diff --git a/Dockerfile b/Dockerfile
index 5dd7dc0..f25cff9 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,7 +2,8 @@
 # build ui #
 ############
 
-FROM node:18.16 AS build-ui
+ARG NODE_VERSION=18.16
+FROM node:${NODE_VERSION} AS build-ui
 
 # env setup
 WORKDIR /usr/local/src/advent22_ui
@@ -19,7 +20,8 @@ RUN yarn build --dest /tmp/advent22_ui/html
 # web app #
 ###########
 
-FROM tiangolo/uvicorn-gunicorn:python3.11-slim AS production
+ARG PYTHON_VERSION=3.11
+FROM tiangolo/uvicorn-gunicorn:python${PYTHON_VERSION}-slim AS production
 
 # add prepared advent22_ui
 COPY --from=build-ui /tmp/advent22_ui /usr/local/share/advent22_ui