Objectives & prerequisites

What Hello Pico Fleet (Wrangler) teaches and what you need before starting.

Learning objectives

NoteLearning objectives
  • Author a single Wrangler-style Fleet fragment (wrangler.oe.academy/v1alpha1) that composes two already-approved InteractionTopologies over the same Manifold RuntimeEnvironment.
  • Name every Pico Element the fleet exposes and attribute each one back to the InteractionTopology that owns its runtime declaration.
  • Declare the channel bindings that participate on the fleet using only Channels already declared by the referenced InteractionTopologies — no invented Channels, no bypass of the underlying labs’ runtime descriptions.
  • Express one fleet-level lifecycle intent (lifecycle.desiredState: deployed with per-topology activation) distinct from per-topology runtime execution.
  • Apply the fleet as a ConfigMap onto the shared manifold namespace and confirm the on-cluster carrier matches the authored fragment verbatim, so the declared truth on the cluster equals what the learner authored.

Prerequisites

NotePrerequisites
  • Completion of the Hello Pico on Manifold lab — the first member InteractionTopology of the fleet.
  • Completion of the Hello Two Picos lab — the second member InteractionTopology of the fleet.
  • Familiarity with the Manifold course Phase 7 vocabulary (RuntimeSubstrate, RuntimeEnvironment, InteractionTopology, Channel, EventType, ControlSurface, OperatorIntent, Observation).
  • A local Kubernetes cluster; see the Kubernetes setup foundation for the canonical minikube install, PATH checks, and first cluster bring-up.

Environment

The canonical local Kubernetes setup — supported OS, install commands for docker, minikube, and kubectl, PATH checks, and a first cluster bring-up — lives in the Kubernetes course setup foundation. Complete that page first so docker, minikube, and kubectl resolve on your PATH.

Lab-specific additions on top of that canonical setup:

  • Reference minikube pin: v1.38.1 was used to author this lab (any v1.34+ should work).

  • Reference minikube profile: manifold-lab — the same profile the two member labs use so the fleet ConfigMap lands in the same cluster.

  • Python 3 with PyYAML on the host — used by verify.sh for the offline spec-compare between fleet.yaml and the ConfigMap carrier. verify.sh falls back to a lighter textual check when PyYAML is unavailable.

  • Estimated time: 20–30 minutes once the two member labs are already deployed.

  • Cleanup step (also repeated at the end of the walkthrough):

    kubectl -n manifold delete configmap hello-pico-fleet --ignore-not-found
rm -rf build/hello-pico-fleet

Pinned versions (reference)

The walkthrough was authored and verified against these versions. Newer versions are expected to work.

  • Kubernetes API version in minikube: v1.31.0
  • Wrangler API group used by the fleet fragment: wrangler.oe.academy/v1alpha1 — the same API group already used by the two member InteractionTopologies in the underlying labs.

One-time setup (optional)

If you have not already deployed the two member labs, deploy Hello Pico on Manifold first, then Hello Two Picos. This lab does not redeploy their manifests; it layers a fleet description over the RuntimeEnvironment they share.