DEV Community

devtocash
devtocash

Posted on • Edited on • Originally published at devtocash.com

Docker Multi-Stage Builds: Slash Your Image Size by 90%

💡 Originally published on devtocash.com — where this guide stays updated. I write hands-on DevOps/SRE deep-dives there weekly.

A typical Node.js Docker image weighs 1.2 GB. A Go binary image can be 800 MB. Most of that weight comes from build tooling, dev dependencies, and operating system packages that have no business being in a production container.

Docker multi-stage builds solve this by separating the build environment from the runtime environment. You compile your application in a fat container with all the tools, then copy only the final artifact into a minimal runtime image.

The result: images that are 10x to 50x smaller, faster to deploy, and more secure.

A multi-stage Dockerfile has multiple FROM statements. Each FROM begins a new stage. You can copy artifacts from earlier stages into later ones, leaving behind everything you do not need.

Key Topics

  • Introduction
  • How Multi-Stage Builds Work
  • Real-World Examples by Language
  • Advanced Multi-Stage Patterns
  • Image Size Optimization Techniques

I walk you through it step-by-step with real Dockerfiles: shrinking a 1.2 GB image down to 80 MB using multi-stage builds — plus the common pitfalls that silently break your CI pipelines. Full guide at devtocash.com

Originally published at devtocash.com


📌 Read the latest version of this guide — plus the full library of DevOps, SRE, Kubernetes, observability & cloud-cost guides — on devtocash.com.

Top comments (0)