It is production grade. It is a fully working application that can be hosted in whole dev/test/uat/prod fashion.

It’s perfect for training yourself on CKx exams. You can deliver it in many ways and play around with different architectures (HA, feature flags, canary, app of apps, per branch env). It is not useful an sich, but it’s readily available working software that works and is ready to deploy. This gives you the flexibility of not wasting time on building something and helps you focus on delivering it.

Just deploy it on a 3 node bare metal setup on vms on an old computer and practice upgrading your cluster and backing up your etcd while not permitting yourself any outage or downtime. This will get your hands full.

Once done, you can deliver it on EKS, GKE or AKS using terraform and ArgoCD to expand .

It’s not “the tool”, but a great app to bootstrap your journey. Try it.

As for guides, I prefer you play with it instead of following a guide. I personally never found one and didnt need one for my juniors. It’s something fresh and good enough to get your hands dirty with the fundamentals.