Dockerfile

# ---- build stage: compile native deps ----
FROM node:22-slim AS build

RUN apt-get update && apt-get install -y --no-install-recommends \
    python3 make g++ \
    && rm -rf /var/lib/apt/lists/*

WORKDIR /app
COPY package.json package-lock.json ./
RUN npm ci --omit=dev

# ---- runtime stage: clean image, compiled deps copied in ----
FROM node:22-slim

WORKDIR /app
COPY --from=build /app/node_modules ./node_modules
COPY package.json ./
COPY src ./src
COPY public ./public

ENV NODE_ENV=production
EXPOSE 3000

HEALTHCHECK --interval=60s --timeout=5s --retries=3 \
  CMD node -e "fetch('http://localhost:'+(process.env.PORT||3000)+'/api/health').then(r=>{if(!r.ok)process.exit(1)}).catch(()=>process.exit(1))"

CMD ["node", "src/server.js"]