#A.6.P:5.1 — System archetype: “same system across environments”

Preface node heading:a-6-p-5-1-system-archetype-same-system-across-environments:13495

#What this page is

This is generated FPF reference text from the specification preface or supporting sections. It helps interpret FPF; it is not FPF Reference product documentation.

#Methodology

Use it to understand how the specification wants to be read, then return to a route, pattern, or work packet for active work. Cite generated IDs only when the wording changes the task decision.

#Content

Tell. An operations note says: “Staging is the same service as Production.” Months later, incident metrics are aggregated “because it is the same service”, and evidence across environments is mixed, producing an incorrect causal story.

Show. Treat “same” as a red-flag umbrella token. Rewrite into an explicit cross-Context relation kind, typed to the facet the draft actually uses (service delivery system sameness for actuals and evidence aggregation; not about promise contents).

Show (candidate‑set note; endpoint facet restoration).

CandidateSetNote(triggerSpan="service" in "same service", position=endpointFacet(p₁)):
- candidates: {promiseContent, serviceAccessPoint, serviceProviderPrincipal, serviceDeliverySystem}
- selected:   serviceDeliverySystem
- why:        the claim is later used to justify mixing operational actuals and evidence (metrics + incident logs);
  local cues point to delivery records or carriers (manifests, config, and test runs), not clause carriers
- consequence: endpoints typecheck as `DeliverySystemRef` participants; clause or provider facets are explicitly out-of-scope

sameDeliverySystemUnder(
  leftDeliverySystemRef  = SystemRef(staging_delivery_system),
  rightDeliverySystemRef = SystemRef(prod_delivery_system),
  scope     = ClaimScope{SLO_family = X, signals = {latency, error_rate}},
  Γ_time    = interval[2025-12-01, 2026-01-31],
  viewpoint = OpsViewpoint,
  witnesses = {deploymentManifestPins, configPins, testRunPins}
)

aggregationAdmissibleIff(
  relationRef  = RelationRef(sameDeliverySystemUnder, SystemRef(staging_delivery_system), SystemRef(prod_delivery_system), ed=…),
  aggregatedActuals = deliveryWorkMetrics,              // actuals
  Γ_time       = interval[2025-12-01, 2026-01-31],
  witnesses    = {metricCarrierPins, incidentLogPins}   // evidence carriers for the actuals
)

Show. Now the relation is auditable: aggregation is admissible only if the relation kind’s admissibility claims say it preserves the needed characteristics under the declared scope and time, and if witnesses exist. Cross-Context reuse is explicit and cannot piggyback on label identity.

Last Updated: 2026-06-17 — upstream FPF commit 646b0b9b (github.com/ailev/FPF)