A practitioner’s category-by-category breakdown of the best tools for automating Kubernetes deployments in 2026 - Argo CD, Flux CD, Helm, Kustomize, KEDA, Kyverno, OPA Gatekeeper, Karpenter, Cluster Autoscaler, Rancher, Portainer, Terraform and Crossplane - plus which 3 to 5 you actually need, and how a platform like Qovery automates the whole chain from cluster creation to upgrades in under 15 minutes.