What Are Chart Extensions
A Chart Extension is a set of optional YAML files you bundle inside a Helm chart to give Platz richer knowledge of your service. Without them, Platz can deploy your chart — users just fill in a raw YAML values blob. With them, your chart gets:
Inputs
platz/values-ui.yaml defines the form users fill in when creating or editing a deployment of your chart. Each entry in the top-level inputs list becomes a form field. Platz collects the submitted values, resolves any references (collection lookups, conditional inputs), and feeds them into the outputs section to produce Helm values and Kubernetes Secrets.
Outputs
The outputs section of values-ui.yaml is what turns submitted form values into Helm values and Kubernetes Secrets. Inputs collect data from the user; outputs map that data into the shape Helm expects.
Features
platz/features.yaml is where you declare chart-level behaviour: how many instances of this chart can exist per cluster, whether the chart should get an auto-generated ingress, whether Platz should poll a status endpoint, what icon to show in the deployment list, where to inject env-level node selectors and tolerations, and a few other knobs.
Actions
platz/actions.yaml defines custom operations that show up in a deployment's Actions menu. Each action describes an HTTP request Platz will make to the deployment's standard ingress when the user invokes it — typically for chart-specific operations like "rotate keys", "force re-index", "drain queue", "run migrations".
Resources
platz/resources.yaml defines resource types — structured child objects your chart's deployments can own. Examples: a Shop owned by a Storefront deployment, a Tenant owned by a SaaS app, a Webhook owned by an integration deployment, a Database owned by a database-provisioner deployment.
Versioning
Chart Extension schemas have evolved over time. Platz supports three versions; this page explains the version history, how Platz picks which one to read, and how to migrate older charts to the current format.