Crossplane v2: the mode enum with one value, the empty DeploymentRuntimeConfig that makes your function pod BestEffort, and the override that fixes it

Artifact — a Crossplane v2 Composition that provisions native Kubernetes children with no cloud provider (v2 composes core resources directly), plus two cited file:lines at a pinned tag: the Composition mode enum proving it has exactly one value (Pipeline) and that Resources is absent from the schema, not deprecated; and the default DeploymentRuntimeConfig proving its spec is empty — the line that makes your function pod land BestEffort with resources: {}. Then the mandatory DeploymentRuntimeConfig override that sizes it — build-mechanics#sizing applied to the platform you are building. The platform has a pod-sizing problem of its own, and that is the phase's thesis in miniature.

Rests on — KRO's bare mechanism, the contrast that makes Crossplane's extra machinery legible; P8's discipline of seeing what an abstraction costs its consumer; and the build-track sizing rule, which the phase's Build-track line points straight at your own function pods.

Topology — platform, continued.

Read — the module framing and the source question below, and the stale-levers note: mode: Resources is a lever older material recommends that no longer exists. Held to the archaeology standard — cite the tool's own Go, and live-verify, because it moves.

Question to answer from the source: in Crossplane at its pinned tag, the Composition mode enum — enumerate its values (there is one) and confirm Resources is absent from the schema, not deprecated. Then find where the default DeploymentRuntimeConfig is created and show its spec is empty — the line that makes your function pod BestEffort. Cite both. The platform you build has the pod-sizing problem you spent P8 learning to see.

Build — install Crossplane, a function, and a Composition that emits native children; observe the function pod ship resources: {}; then fix it:

helm install crossplane crossplane-stable/crossplane -n crossplane-system --create-namespace
kubectl apply -f function-patch-and-transform.yaml   # functions are mandatory now
kubectl apply -f webapp-xrd.yaml -f webapp-composition.yaml   # mode: Pipeline — the only value
# the hazard, before the fix:
kubectl get pod -n crossplane-system -l pkg.crossplane.io/function -o \
  jsonpath='{.items[0].spec.containers[0].resources}{"\n"}'   # {} — BestEffort, no request, no limit
# the mandatory override:
kubectl apply -f - <<'YAML'
apiVersion: pkg.crossplane.io/v1beta1
kind: DeploymentRuntimeConfig
metadata: {name: sized}
spec:
  deploymentTemplate:
    spec:
      template:
        spec:
          containers:
          - name: package-runtime
            resources: {requests: {memory: 128Mi}, limits: {memory: 256Mi}}
YAML

Verify from outside — both mechanism claims are file:line a reader clones and opens: the mode enum with one entry, and the empty default runtime config. "Crossplane composes it" fails the gate; <file>:<line>@<tag> for each passes. The resources: {} on the function pod is a live jsonpath output, not an assertion — and the override changing it to a sized pod is the fix, checkable the same way.

Expect — a Composition provisioning native children with no provider, a function pod that ships unbounded until you size it, and two citations a hostile reader can verify. The DeploymentRuntimeConfig override is non-optional on this node — 12.C4 is what happens without it.

Write down — the two cited Crossplane lines (the mode enum, the empty runtime config) and the override that sized the function pod. Combined with the KRO baseline: what the extra machinery buys, and what it costs.

Footprint note — Crossplane core is 3 pods, ~384Mi plus one function pod that is BestEffort until sized — the exact hazard class that ruled out Argo CD, now on a pod you cannot avoid. On the single platform node the override is mandatory.

Teardown — keep the XRD, Composition and a DeploymentRuntimeConfig for the Helm contrast and the capstone; 12.C4 deliberately removes the override next, so note its current state. The topology stays.