Docker
Containers from first principles to production images, networks, and volumes.
“Duolingo for DevOps. One concept = one 2-4 minute video. Never introduce a concept before its prerequisites. Every lesson builds on the last.”
47 / 47 lessons readyaudience: developers & devops47 lessons planned
1. Docker
47 lessonsContainers are the fundamental packaging unit of modern deployment. Everything after (Kubernetes, CI/CD, Helm) assumes you understand what a container is and why it matters.
Why Docker Exists
The Dockerfile
Running Containers
Volumes and Data
Docker Networks
Docker Compose
Registries and Distribution
Best Practices and Security
- Slimming an image — alpine, distroless3m 30sWatch →
- Non-root user in containers3m 00sWatch →
- Read-only filesystems3m 30sWatch →
- Image vulnerability scanning3m 30sWatch →
- Never bake secrets into images3m 30sWatch →
- CPU and memory limits at runtime3m 30sWatch →
- HEALTHCHECK — proving your container is alive3m 30sWatch →
- Mini project: containerize a Node app5m 00sWatch →