kustomize

Generate environment-specific Kubernetes configurations using bases, overlays, and patches.

53|1|Updated Dec 18, 2025

Search Tags:#kubectl #patch #kustomize #config-management #overlay

Ready to run

npx skills add https://github.com/cosmix/claude-code-setup --skill kustomize

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: kustomize
Source: https://github.com/cosmix/claude-code-setup/tree/main/skills/kustomize
Command: npx skills add https://github.com/cosmix/claude-code-setup --skill kustomize

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Kustomize enables declarative, environment-specific customization of Kubernetes manifests without templating, using bases, overlays, and patches to compose final configurations.

Core Features & Use Cases

Base/Overlay structure: Organize resources for multiple environments.
Patches and transformers: Fine-grained updates without templates.
Config generation: ConfigMap/Secret generators and image replacements.
Use Case: Manage dev/stage/prod configurations with a single base set of manifests.

Quick Start

In the base, create a kustomization.yaml referencing resources; build with kubectl kustomize base or kustomize build, then apply via kubectl -k overlays/dev.

Frequently Asked Questions about kustomize

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I manage Kubernetes configurations across multiple environments without templating?▼

Kustomize automates Kubernetes configuration management using bases and overlays to customize manifests declaratively. Organize your base resources in a directory with kustomization.yaml, then create environment-specific overlays that patch or merge configurations for dev, staging, and production without template syntax.

Can I use patches to customize Kubernetes manifests instead of templates?▼

Yes, kustomize applies strategic merge and JSON Patch strategies to modify Kubernetes resources without templating. Patches let you fine-grained update specific fields—image versions, replicas, environment variables—while keeping your base manifests clean and reusable.

How do I generate ConfigMaps and Secrets in Kubernetes configuration management?▼

Kustomize includes generators to automatically create ConfigMaps and Secrets from files or literals, and image replacement transformers to update container images across resources. Define generators in kustomization.yaml to produce environment-specific configurations during the build step.

What's the difference between using kustomize and templating for Kubernetes configs?▼

Kustomize uses declarative overlays, patches, and components instead of template logic, reducing complexity and improving readability. It composes final manifests by merging structured patches rather than rendering templates, making configurations easier to review and audit.

Does kustomize work with kubectl for applying configurations?▼

Yes, kustomize integrates directly with kubectl via the -k flag. Run kubectl apply -k overlays/dev to build and apply environment-specific configurations in a single command, or use kubectl kustomize to preview the final manifest before applying.

Can I organize Kubernetes resources for dev, staging, and production with kustomize?▼

Yes, kustomize's base/overlay structure is designed for multi-environment deployments. Create a shared base with common resources, then define overlays for each environment that patch or add environment-specific settings, enabling a single source of truth across deployment stages.