kustomize

Table of contents

  1. kustomize
    1. Information
    2. Releases
    3. Installation
    4. Completion
    5. kubectl integration
    6. Usage
      1. Make a kustomization file
    7. Bugs
    8. Links

kustomize lets you customize raw, template-free YAML files for multiple purposes, leaving the original YAML untouched and usable as is.

kustomize targets kubernetes; it understands and can patch kubernetes style API objects. It’s like make, in that what it does is declared in a file, and it’s like sed, in that it emits edited text.


Information

Source | Tracker | VCS | QA | Bugs


Releases

  • 5.5.0+ds-4 (sid | unstable )

If you are using an unlisted debian version probably that means this package it’s not available.


Installation

apt install kustomize

Completion

Completions will be installed for bash, zsh and fish shells.


kubectl integration

To find the kustomize version embedded in recent versions of kubectl, run kubectl version:

> kubectl version --client
Client Version: v1.31.0
Kustomize Version: v5.4.2

Usage

Make a kustomization file

In some directory containing your YAML resource files (deployments, services, configmaps, etc.), create a kustomization file.

This file should declare those resources, and any customization to apply to them, e.g. add a common label.


base: kustomization + resources

kustomization.yaml                                      deployment.yaml                                                 service.yaml
+---------------------------------------------+         +-------------------------------------------------------+       +-----------------------------------+
| apiVersion: kustomize.config.k8s.io/v1beta1 |         | apiVersion: apps/v1                                   |       | apiVersion: v1                    |
| kind: Kustomization                         |         | kind: Deployment                                      |       | kind: Service                     |
| labels:                                     |         | metadata:                                             |       | metadata:                         |
| - includeSelectors: true                    |         |   name: myapp                                         |       |   name: myapp                     |
|   pairs:                                    |         | spec:                                                 |       | spec:                             |
|     app: myapp                              |         |   selector:                                           |       |   selector:                       |
| resources:                                  |         |     matchLabels:                                      |       |     app: myapp                    |
|   - deployment.yaml                         |         |       app: myapp                                      |       |   ports:                          |
|   - service.yaml                            |         |   template:                                           |       |     - port: 6060                  |
| configMapGenerator:                         |         |     metadata:                                         |       |       targetPort: 6060            |
|   - name: myapp-map                         |         |       labels:                                         |       +-----------------------------------+
|     literals:                               |         |         app: myapp                                    |
|       - KEY=value                           |         |     spec:                                             |
+---------------------------------------------+         |       containers:                                     |
                                                        |         - name: myapp                                 |
                                                        |           image: myapp                                |
                                                        |           resources:                                  |
                                                        |             limits:                                   |
                                                        |               memory: "128Mi"                         |
                                                        |               cpu: "500m"                             |
                                                        |           ports:                                      |
                                                        |             - containerPort: 6060                     |
                                                        +-------------------------------------------------------+

File structure:

~/someApp
├── deployment.yaml
├── kustomization.yaml
└── service.yaml

The resources in this directory could be a fork of someone else’s configuration. If so, you can easily rebase from the source material to capture improvements, because you don’t modify the resources directly.

Generate customized YAML with:

kustomize build ~/someApp

The YAML can be directly applied to a cluster:

kustomize build ~/someApp | kubectl apply -f -

For more examples check upstream examples folder


Bugs

Bug ID Title Severity Status Arrival Last Modified Submitter
1098476 kustomize: binary-all FTBFS serious done 2025-02-21 00:45:01 +0000 2025-02-21 01:24:03 +0000 Adrian Bunk ([email protected])