{
  "uid": "cogitave.learn.build-a-diyar-solution.summary",
  "kind": "moduleUnit",
  "href": "/modules/build-a-diyar-solution/summary/",
  "title": "Summary",
  "summary": "",
  "type": null,
  "products": [],
  "roles": [],
  "levels": [],
  "subjects": [],
  "headings": [
    "Next steps"
  ],
  "source": "You can now describe, precisely, how a Diyar device becomes a certified\nsolution - through signed documents and firmware-compiled registries, not\ncustom code written per customer.\n\nIn this module, you:\n\n- Learned what a signed device profile configures at boot (channels,\n  actuators, safety limits, process parameters, verdict binding), why an\n  unverifiable or invalid one is a loud refuse-to-start, and why append-only\n  evolution only lets a revision add channels or actuators, never rename or\n  remove one, within a major version.\n- Explained the HAL seam - `TempSource` / `RelayBank` / `MonotonicClock` -\n  that lets the same safety-critical core drive local hardware or a Modbus\n  (TCP or RTU) field device unchanged, and why a networked heat source without\n  a declared watchdog is rejected at load.\n- Explained why the `VerdictEngine` trait, not a valid signature alone, is\n  what lets a process rule run: a signed profile can only name an engine\n  already listed in the firmware-compiled `CERTIFIED_ENGINES` table, and the\n  reserved-id rule stops a generic engine from laundering a product engine's\n  identity.\n- Described the three documents in an app package (manifest, grant, profile),\n  why each is deliberately free of any evaluable construct, the three\n  non-implicative authority tiers (Observe / Operate / Actuate), and how\n  `effective_authority` computes A n B n C offline - plus the\n  firmware-compiled `CERTIFIED_ACTUATIONS` allowlist that gates hazardous\n  actuation on top of that.\n- Walked ISPM-15 end to end as one worked solution built entirely on that\n  machinery, why its verdict engine is byte-parity-locked to a frozen\n  reference oracle, and the honest limits: no third-party safety certification\n  exists yet, and the non-thermal siblings (`pressure-hold`, `coldroom-hold`,\n  `steam-sterilizer-f0`) are internal proof fixtures, not customer\n  deployments.\n\nThat completes the three modules of the \"Introduction to Cogitave Diyar\"\npath: understanding what Diyar is, its safety and evidence model, and now how\na device becomes a certified solution.\n\n## Next steps\n\n- @cogitave.learn.paths.introduction-to-diyar - return to the path to claim\n  your trophy.\n",
  "partOf": "cogitave.learn.build-a-diyar-solution",
  "durationInMinutes": 3,
  "quiz": null
}