What Is Docker and Why Use It?
Docker lets you package applications inside containers. It eliminates the classic "works on my machine" problem and guarantees consistency between development, staging, and production environments.
Related guides: What is DNS, settings · Domain names & WHOIS lookup · Hosting types guide · Nginx configuration · Plesk panel guide
Writing a Dockerfile
A good Dockerfile is layered and takes full advantage of the build cache. Place frequently changing layers toward the end of the file.
# Multi-stage build
FROM node:20-alpine AS builder
WORKDIR /app
COPY package*.json ./
RUN npm ci --only=production
COPY . .
RUN npm run build
FROM node:20-alpine
WORKDIR /app
COPY --from=builder /app/node_modules ./node_modules
COPY --from=builder /app/dist ./dist
COPY --from=builder /app/package.json ./
EXPOSE 3000
USER node
CMD ["node", "dist/server.js"]Multi-Container Setups with Docker Compose
Most applications need more than one service: web server, database, cache, reverse proxy. Docker Compose lets you declare them in a single YAML file.
version: '3.8'
services:
app:
build: .
ports: ["3000:3000"]
environment:
- NODE_ENV=production
- DB_HOST=db
depends_on: [db, redis]
db:
image: postgres:16-alpine
volumes: ["pgdata:/var/lib/postgresql/data"]
environment:
POSTGRES_DB: myapp
POSTGRES_PASSWORD_FILE: /run/secrets/db_pass
redis:
image: redis:7-alpine
volumes:
pgdata:Production Best Practices
1) Do not run as root — add USER node. 2) Use a .dockerignore file. 3) Add a health check. 4) Stream logs to stdout/stderr. 5) Manage secrets via environment variables or Docker secrets.
Modern Web Hosting and Server Infrastructure
A performant web hosting service rests on three infrastructure decisions: NVMe SSD disks (4-6× IOPS over SATA SSD), LiteSpeed Web Server or Nginx + LSCache (9× request capacity over Apache) and CloudLinux + Imunify360 isolation. The hosting provider's control panel (cPanel, Plesk, DirectAdmin), daily backup policy, data center location and support response time make a big difference too. Turkish locations give low latency to local visitors, while Hetzner Frankfurt or OVH Roubaix suit global traffic. As your site grows, transitioning from shared hosting to VPS to dedicated server scales CPU/RAM/disk to your needs.
Conclusion
Docker is an essential part of modern deployment. Integrate it into your CI/CD pipeline to get fully automated build and release flows — the same approach KEYDAL uses across its own services.