4 lessons
ConfigMaps and Secrets
Injecting configuration and sensitive values into Pods without baking them into images, the Kubernetes way.
StatefulSets for databases and stateful apps
Why Deployments aren't a good fit for databases, and what StatefulSets do differently.
Jobs and CronJobs
Running work to completion instead of continuously — batch tasks, migrations, and scheduled jobs.
Resource limits and health probes
Requests and limits for CPU/memory, and the three types of health probes that let Kubernetes know if a Pod is actually working.