Docker multi-stage para APIs Node

Un Dockerfile naive con node:20 y npm install te deja imágenes de 1GB+. Multi-stage lo arregla.

dockerfile
FROM node:20-alpine AS builder
WORKDIR /app
COPY package*.json ./
RUN npm ci
COPY . .
RUN npm run build

FROM node:20-alpine AS runner
WORKDIR /app
ENV NODE_ENV=production
COPY --from=builder /app/dist ./dist
COPY --from=builder /app/node_modules ./node_modules
CMD ["node", "dist/main.js"]

Usá .dockerignore agresivo y npm ci --omit=dev en la etapa final para recortar aún más.