Docker — Containerization for Monorepos

Docker best practices for Node.js monorepos with Yarn 4 Berry.

Key Principles

• Minimal images: Alpine-based, only runtime dependencies in final stage
• Layer caching order: system deps → package manifests → install → source → build
• Non-root users: Create app user, never run as root in production
• One process per container: Compose multiple containers, not multiple processes
• Health checks on every service: Use the existing /health endpoint

Image Optimization Quick Reference

• Use node:22-alpine as base
• Multi-stage builds: exclude build tools from final image
• yarn cache clean after install