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docs/add-ons/gitlab-runner.md

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+# gitlab-runner
+
+The GitLab runner Helm Chart is the official way of deploying a GitLab runner on a Kubernetes cluster. The chart configures a GitLab runner which runs using the Kubernetes executor. For each new job, it provisions a pod within the specified namespace.
+
+For complete project documentation, please see [GitLab's documentation](https://docs.gitlab.com/runner/install/kubernetes.html). 
+
+## Usage
+
+The GitLab Runner can be deployed by enabling the add-on via the following:
+
+```hcl
+enable_gitlab_runner = true
+```
+
+At minimum a runner token must be supplied. This can be done directly, as a deploy-time value:
+
+```hcl
+  gitlab_runner_helm_config = {
+    set_sensitive = [
+      { name = "runnerRegistrationToken", value = "someTokenValue" },
+    ]
+  }
+```
+
+or using an existing secret, such as:
+
+```yaml
+apiVersion: v1
+kind: Secret
+metadata:
+  name: gitlab-runner-secret
+type: Opaque
+data:
+  runner-registration-token: "NlZrN1pzb3NxUXlmcmVBeFhUWnIK" #base64 encoded registration token
+  runner-token: ""
+```
+and passing it to the chart:
+
+```hcl
+  gitlab_runner_helm_config = {
+    set = [
+      { name = "runners.secret", value = "gitlab-runner-secret" }
+    ]
+  }
+```
+
+By default the runner is registered on the cloud instance `gitlab.com`. An self-hosted instance can also be configured:
+
+```hcl
+  gitlab_runner_helm_config = {
+    set = [
+      { name = "gitlabUrl", value = "https://mygitlab.com" }
+    ]
+  }
+```