Production Deployment - Multi-Stage Docker Builds, PM2 Process Manager & Nginx

Writing functional server code is only half the battle; deploying hardened, zero-downtime services to the cloud is what transforms you into a complete engineer. In this tutorial, you will master production deployments with Multi-Stage Docker builds, PM2 Process Manager, and Nginx Reverse Proxying.

Figure 9: Enterprise Production Architecture: Nginx Reverse Proxy > PM2 Process Cluster > Containerized Node.js Microservices

1. Production Multi-Stage Dockerfile

# --- STAGE 1: Dependency Installation & Build ---
FROM node:22-alpine AS builder
WORKDIR /app

# Copy dependency manifests first to leverage Docker layer caching
COPY package*.json ./
RUN npm ci

# Copy source code and build
COPY . .

# Prune devDependencies to keep image lean
RUN npm prune --production

# --- STAGE 2: Lightweight Production Runtime ---
FROM node:22-alpine AS runner
WORKDIR /app

ENV NODE_ENV=production
ENV PORT=3000

# Security: Run as unprivileged non-root user bundled in node:alpine
USER node

# Copy only production artifacts from builder stage
COPY --chown=node:node --from=builder /app/package*.json ./
COPY --chown=node:node --from=builder /app/node_modules ./node_modules
COPY --chown=node:node --from=builder /app .

EXPOSE 3000

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

2. PM2 Production Process Management (ecosystem.config.js)

module.exports = {
  apps: [{
    name: 'veewom-api',
    script: 'server.js',
    instances: 'max',       // Utilize all available CPU cores automatically!
    exec_mode: 'cluster',   // Cluster mode
    autorestart: true,      // Restart if application crashes
    watch: false,           // Never watch files in production
    max_memory_restart: '1G', // Restart if RAM exceeds 1GB
    env_production: {
      NODE_ENV: 'production',
      PORT: 3000
    }
  }]
};

Essential PM2 Commands:

pm2 start ecosystem.config.js --env production  # Start cluster
pm2 reload veewom-api                           # Zero-downtime rolling reload!
pm2 status                                      # Inspect CPU/RAM of all workers
pm2 logs veewom-api                             # Stream aggregated logs

3. Nginx Reverse Proxy Configuration

server {
    listen 80;
    server_name api.veewom.com;

    location / {
        proxy_pass http://127.0.0.1:3000;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_cache_bypass $http_upgrade;
    }
}