Docker Containerization Patterns

Quick Guide: Docker with BuildKit for containerizing Node.js/TypeScript applications. Multi-stage builds for minimal production images (1GB to under 100MB). Docker Compose v2 for development environments. BuildKit cache mounts for 10x faster dependency installs. Non-root users, health checks, and secret mounts for production security. Alpine for size, Debian slim for compatibility.

<critical_requirements>

CRITICAL: Before Using This Skill

(You MUST use multi-stage builds for production images - NEVER ship dev dependencies, TypeScript compiler, or source files in production)

(You MUST run containers as non-root user - NEVER run production containers as root (default))

(You MUST use CMD ["node", "server.js"] (exec form) - NEVER use npm start or shell form as CMD)

(You MUST use BuildKit secret mounts for sensitive data at build time - NEVER use ARG or ENV for secrets)

(You MUST copy package.json/lockfile BEFORE source code - NEVER COPY . . before npm ci (breaks layer cache))