Adding argocd image

content/posts/application_kustomize_image.md

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+title = "Application Kustomize image"
+date = 2026-02-28T00:00:00-05:00
+draft = false
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+
+When creating [Applications](https://argo-cd.readthedocs.io/en/latest/user-guide/application-specification/) in [Argocd](https://argo-cd.readthedocs.io/en/stable/) I always prefer to use [kustomize](https://argo-cd.readthedocs.io/en/stable/user-guide/kustomize/) for my own manifests. It allows me to create a simple "base" of manifests and then alter it for the specific use case via the `kustomize` attribute within the application. This allows a single place (the `Application` or `ApplicationSet`) to stores all the high level information for configuring the installation.
+
+While working on one project or another, I don't remember anymore why I needed to figure this out, I noticed the `images` attribute works differently in Argocd than it does in kustomize. **Since you the reader might be interested in the solution as opposed to the exploration, let me get that out of the way now**:
+
+_format_: `- [old_image_name=]<image_name>:<image_tag>`
+
+Example:
+
+```yaml
+spec:
+  source:
+    path: examples/helloWorld
+    repoURL: 'https://github.com/kubernetes-sigs/kustomize'
+    targetRevision: HEAD
+    kustomize:
+      images:
+        - nginx=docker.io/nginx:v1.1.2
+```
+
+Documentation for this syntax was hard to find, so I had to go digging through the [source](https://github.com/argoproj/argo-cd/blob/a3b4c8327f38ef2edfb3be6c68f96729ce98f9d8/pkg/apis/application/v1alpha1/types.go#L653-L654) to find out how it should be formatted.
+
+Kustomize is less concise than argocd, having you [spell out each part](https://github.com/kubernetes-sigs/kustomize/blob/master/examples/image.md). The same example above in kustomize would look like this.
+
+```yaml
+images:
+- name: nginx
+  newName: docker.io/nginx
+  newTag: v1.1.2
+```