Kustomize
February 22, 2026
What it is
Kustomize customizes Kubernetes YAML with overlays (base + patches). No templating language; built into kubectl -k. Good for environment-specific config (dev/stage/prod).
Usage
Define base manifests; overlay patches for envs; merge and patch images, labels, replicas; use with GitOps (Argo CD, Flux).
Pros and cons
| Pros | Cons |
|---|---|
| No new syntax; plain YAML | Less flexible than Helm for complex parameterization |
| Native in kubectl | |
| Clear overlay model | |
| GitOps-friendly |
Alternatives
Helm (templating), raw YAML. Why Kustomize: Prefer YAML-only and overlays over Helm templating.
Links
- Homepage: https://kustomize.io/
- Documentation: https://kustomize.io/documentation
- Source: https://github.com/kubernetes-sigs/kustomize