I85PREP
⌘ K
CGOA study materials
CGOA study resources

CGOA: Tooling

CGOA · Work through your exam, one topic at a time.

All guide sections

Tooling

The Tooling domain tests your ability to place tools in the GitOps stack and distinguish a reconciler from a packaging, templating, policy, or secrets tool. Exam questions often name a tool and ask which role it plays.

Tool categories

  • GitOps controllers: Argo CD and Flux are the canonical pull-based reconcilers. Argo CD uses Application and ApplicationSet resources and reports sync and health status. Flux v2 uses controllers such as source-controller, kustomize-controller, and helm-controller, with GitRepository, Kustomization, and HelmRelease objects.
  • Templating and packaging: Kustomize customizes YAML without templates; Helm packages and templates Kubernetes manifests. Neither is a GitOps reconciler by itself.
  • Progressive delivery: Argo Rollouts and Flagger manage canary and blue-green traffic shifts; they complement a GitOps controller.
  • Secrets: Sealed Secrets, SOPS, and External Secrets keep encrypted or external secret material out of plaintext Git.
  • Policy: Kyverno and OPA Gatekeeper enforce admission policies; they are not deployment controllers.
  • CI: builds, tests, and scans artifacts; in GitOps it should not need to push into the cluster.

Worked example

A team wants Helm releases reconciled from Git and already uses Flux. They define a GitRepository for the config repo, a HelmRelease for the chart and values, and a Kustomization to apply the Flux objects. The source-controller fetches the revision; helm-controller reconciles the release. If they instead choose Argo CD, they would define an Application pointing at the chart and values, and Argo CD would pull and reconcile. The reasoning: both are valid GitOps controllers; the choice changes the API objects, not the principles. Kustomize or Helm alone would not provide continuous reconciliation.

Traps that cost marks

Calling Kustomize or Helm a GitOps controller. Confusing Argo CD with Argo Workflows or Argo Rollouts. Treating Flux v1 and v2 as the same architecture. Assuming a CI tool is the reconciler. Assuming a policy engine deploys workloads. Believing tool choice changes the four principles.