diff --git a/Dockerfile b/Dockerfile
index a3f18c5..928c6b0 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -3,9 +3,13 @@ FROM node:20-alpine
 
 WORKDIR /app
 
+# Install libvips build deps for sharp (removed after npm ci for smaller image)
+RUN apk add --no-cache build-base python3
+
 # Copy package files first for better layer caching
 COPY package*.json ./
-RUN npm ci --omit=dev
+RUN npm ci --omit=dev && \
+    apk del build-base python3
 
 # Copy application code
 COPY server.js ./