CSE36 · CI/CD, GitOps & SRE
Docker Image Layers
Order the Dockerfile steps so a code change rebuilds in seconds, not minutes, and the image stays small.
🎯 You will learn to
- Read image layers
- Use the build cache
- Keep images small and safe
📘 Guided lab
This mission is a guided walkthrough: follow the steps on your own computer or practice account. The in-browser simulator for it is planned for a later release.
✅ Steps & checkpoints
🗺️ Docker layer cache
Each Dockerfile line is a cached layer; copying dependency files before source means a code change rebuilds only the last layers.
The 2D diagram shows the exact flow, ports and trust boundaries. The 3D scene is a concept view of the same parts; packets travel along the same arrows.
🤔 Think about it
Why should the image not contain secrets?
🛡️ Safety & cost
Pipelines run in a simulator. No repository or cluster is changed.
🧹 Cleanup
Nothing to clean up.
📚 Reference documents
- Docker: get started · Docker
- GitHub Actions documentation · GitHub
- Argo CD documentation · Argo Project
- Site Reliability Engineering book · Google SRE
Official sources, checked on 5 Nov 2026. Cloud services change often; check the official page before relying on a feature. All references