---
id: TST-PFM-DJE-158
title: Capacity signals
kind: unit
product_area: platform
module: data-job-engine
revision: 1
status: draft
source_sha:
  services-platform: ad3f6a6582843008ed0f5a17b131878d15829af1
  macroservice-libraries: 54536a441935c6e09fdb7f96f0bec71c52ba4e03
  services-crm: a8d1364f1dd44b723bb5f9acba12f983e9ec8d69
  services-membership: 5994c270e8a37a30f848e99ba5b5ee6b87c08893
  react-console: baf6dae382d6f41dce976c7f848667ccc37e076f
repository: services-platform
files:
  - modules/capacity/tests/unit/services/capacity/capacity-signals.spec.ts
implements: []
environment: local
implementation_state: implemented
latest_result: not-run
latest_run_at: null
latest_run_ref: null
conformance: not-verified
estimated_minutes: 1
isolation: In-memory fixtures and restored dependency doubles.
evidence:
  - 'services-platform:modules/capacity/tests/unit/services/capacity/capacity-signals.spec.ts'
assertion_inventory:
  - capacity signals
  - the window
  - ends a minute before the current minute and spans six minutes
  - the queries
  - 'read the cluster, the proxy and each API stage by its CloudWatch statistic'
  - the readings
  - 'are one a minute, oldest first, whatever order the datapoints came in'
  - read the proxy borrow latency in milliseconds
  - carry null for a metric with no datapoint in the minute
  - key each API latency by the API name
  - capacity latency baseline
  - is the median of the hourly p95 values
  - has no value for no datapoints
  - is due when none is stored
  - is not due when it was computed less than an hour ago
  - reads an empty parameter as no baseline
registration_note: Registration describes existing source; the suite is not executed by this documentation job.
---

# Capacity signals

## Verification Boundary

The suite checks an isolated production calculation, declaration or adapter. The structured assertion inventory records the checks present at the pinned revision.

## What This Suite Proves

The existing checks exercise capacity signals. The specification bindings identify the narrower outcomes supported by those assertions.

## What It Does Not Prove

An isolated check does not establish a deployed workflow, database enforcement or complete feature acceptance.

## Real Dependencies and Test Doubles

The production function or declaration is exercised with in-memory inputs and dependency doubles. This boundary does not require a live database.

## Must Not Be Doubled

The production function under examination and its returned decisions remain real; replacing their answers defeats the check.