I've started trying to learn more about kubernetes by setting up some personal services and it seems like everything I find online points to some helm chart to install.

I think because I don't fully understand k8s, yet, helm seems too magical. It's abstracting away what I already don't understand and doesn't feel right.

For now, I've been focusing on writing my manifests and applying them with kubectl to get a feel for what's going on under the hood. Maybe a time will come where it's a tool that I'll need to reach for, though.

So how do you run stateful workloads? E.g. postgres or mysql?

Generally speaking, you probably shouldn't run databases in k8s unless you need to scale them dynamically, or cloud disk performance is acceptable to you. Having said that, k8s is getting a lot of support for running databases on local disks. A lot of newsql databases (CockroachDB, TiDB, Yugabyte, Vitess, etc) are shipping with strong k8s support/integration.

As a matter of fact, we recently released the 1.0 GA version of TiDB Operator: https://github.com/pingcap/tidb-operator