diff --git a/Dockerfile b/Dockerfile
index 3f1374d..f7d8d51 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -11,6 +11,11 @@ RUN npm install
 COPY . .
 # Use a temporary DB for generation
 ENV DATABASE_URL="file:./temp.db"
+
+# Build arguments for public env vars
+ARG NEXT_PUBLIC_VAPID_PUBLIC_KEY
+ENV NEXT_PUBLIC_VAPID_PUBLIC_KEY=$NEXT_PUBLIC_VAPID_PUBLIC_KEY
+
 RUN npx prisma generate
 RUN npm run build
 
diff --git a/README.md b/README.md
index a56276b..b881551 100644
--- a/README.md
+++ b/README.md
@@ -73,8 +73,10 @@ docker-compose up -d --build
 
 Mit **Docker CLI**:
 ```bash
-# Image bauen
-docker build -t cat-sitting-planner .
+# Image bauen (Beachte: Public Vars müssen beim Build da sein!)
+docker build \
+  --build-arg NEXT_PUBLIC_VAPID_PUBLIC_KEY="DEIN_PUBLIC_KEY" \
+  -t cat-sitting-planner .
 
 # Container starten
 # Container starten