Render the same Jsonnet for many clusters or tenants without writing a snippet by hand for each one: let a Flux Operator ResourceSet template a JsonnetSnippet per input, and JaaS renders each instance into its own ExternalArtifact. The ResourceSet supplies the per-instance values through Go template substitution; JaaS does the evaluation. There is no ResourceSet field in the JaaS API — you use the two together: the ResourceSet templates ordinary JsonnetSnippet CRs, which JaaS reconciles like any other. This needs the Flux Operator installed alongside JaaS in the operator mode described under operator mode .

The worked example below fans the maintained operator dashboard (see Dashboard ) out across a fleet: each cluster gets its own rendered dashboard, scoped to its own Prometheus and labelled with its own title.

1. Declare the per-instance inputs

A ResourceSetInputProvider of .spec.type Static exports a fixed list of inputs from .spec.defaultValues. List one entry per cluster, each carrying the values the dashboard’s top-level arguments need:

apiVersion: fluxcd.controlplane.io/v1
kind: ResourceSetInputProvider
metadata:
  name: clusters
  namespace: monitoring
spec:
  type: Static
  defaultValues:
    clusters:
      - name: prod
        datasource: prometheus-prod
        selector: 'cluster="prod"'
      - name: staging
        datasource: prometheus-staging
        selector: 'cluster="staging"'

Other provider types export inputs from a live source instead — Git branches, pull requests, or OCI artifact tags — and .spec.schedule (with cron, timeZone, and window) gates when those inputs refresh, so the templated snippets only change inside the window. The time-based delivery guide covers that pattern.

2. Template a JsonnetSnippet per input

A ResourceSet consumes the provider through .spec.inputsFrom, then templates its .spec.resources once per resolved input. Each rendered JsonnetSnippet points at the dashboard OCIRepository and threads the per-cluster values into spec.tlas with << inputs.x >> substitution:

apiVersion: fluxcd.controlplane.io/v1
kind: ResourceSet
metadata:
  name: cluster-dashboards
  namespace: monitoring
spec:
  serviceAccountName: dashboards-tenant
  inputsFrom:
    - kind: ResourceSetInputProvider
      name: clusters
  resources:
    - apiVersion: jaas.metio.wtf/v1
      kind: JsonnetSnippet
      metadata:
        name: dashboard-<< inputs.name >>
        namespace: monitoring
      spec:
        serviceAccountName: dashboards-tenant
        sourceRef:
          kind: OCIRepository
          name: jaas-dashboard
        libraries:
          - kind: JsonnetLibrary
            name: grafonnet
        tlas:
          datasource: ["<< inputs.datasource >>"]
          title: ["JaaS operator — << inputs.name >>"]
          selector: ['<< inputs.selector >>']
        interval: 10m
        output: rendered

The ResourceSet creates dashboard-prod and dashboard-staging, each with its own datasource UID, title, and query selector. JaaS reconciles each snippet independently and publishes one ExternalArtifact per cluster, named after the snippet. Point a GrafanaDashboard at each artifact exactly as the Dashboard page shows, and the grafana-operator pushes the per-cluster JSON to Grafana.

The same shape generalises beyond dashboards: any per-tenant or per-environment Jsonnet — manifest libraries, config documents — fans out the same way. Add a cluster to the provider’s list and the ResourceSet renders one more snippet; no new snippet YAML by hand.

For where this pattern sits relative to running JaaS or the Flux Operator alone, see JaaS vs Flux Operator ResourceSet .