It is built around the [Kubernetes Ingress resource](https://kubernetes.io/docs/concepts/services-networking/ingress/), using a [ConfigMap](https://kubernetes.io/docs/concepts/configuration/configmap/) to store the controller configuration.
You can learn more about using [Ingress](http://kubernetes.io/docs/user-guide/ingress/) in the official [Kubernetes documentation](https://docs.k8s.io).