Dockerfile with bun for backend

backend/Dockerfile.bun

@@ -0,0 +1,20 @@
+FROM oven/bun:1-alpine
+
+WORKDIR /app
+
+# Install dependencies first (layer caching)
+# bun install is compatible with npm package.json / package-lock.json
+COPY package*.json ./
+RUN bun install --production
+
+# Copy application source
+COPY . .
+
+# Expose backend API port
+EXPOSE 3001
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=10s --start-period=20s --retries=3 \
+  CMD bun -e "require('http').get('http://localhost:3001/api/health', r => r.statusCode === 200 ? process.exit(0) : process.exit(1)).on('error', () => process.exit(1))"
+
+CMD ["bun", "run", "server.js"]