# K8S Operators

A Site Reliability Engineer (SRE) is a person that operates an application by writing software. They are an engineer, a developer, who knows how to develop software specifically for a particular application domain. The resulting piece of software has an application's operational domain knowledge programmed into it.

An Operator is an application-specific controller that extends the Kubernetes API to create, configure, and manage instances of complex stateful applications on behalf of a Kubernetes user. It builds upon the basic Kubernetes resource and controller concepts but includes domain or application-specific knowledge to automate common tasks.

![](/files/-LhdGD6VyLbXPNgSFULH)

**Prometheus Operator**

{% embed url="<https://github.com/coreos/prometheus-operator>" %}

**ETCD Operator**

{% embed url="<https://github.com/coreos/etcd-operator>" %}

Reference&#x73;**:**

{% embed url="<https://coreos.com/blog/introducing-operators.html>" %}


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