Docker Next.js Standalone

# syntax=docker/dockerfile:1
FROM node:20-alpine AS base

# Install dependencies only when needed
FROM base AS deps
RUN apk add --no-cache libc6-compat
WORKDIR /app

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

# Build the source code
FROM base AS builder
WORKDIR /app
COPY --from=deps /app/node_modules ./node_modules
COPY . .

ENV NEXT_TELEMETRY_DISABLED=1
RUN npm run build

# Production image — copy only the standalone output
FROM base AS runner
WORKDIR /app

ENV NODE_ENV=production
ENV NEXT_TELEMETRY_DISABLED=1

RUN addgroup --system --gid 1001 nodejs
RUN adduser --system --uid 1001 nextjs

COPY --from=builder /app/public ./public

# Leverage output traces to reduce image size
COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static

USER nextjs

EXPOSE 3000
ENV PORT=3000
ENV HOSTNAME="0.0.0.0"

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