# NativeCAD 0.18.3 "Chan" — `nativecad-impactdiff`: the PCB impact diff for servers

**170 tools, the same as 0.18.2.** Installs on 0.17.2 and later get this release through the self-update: `cad_configure {update:"now"}` installs it, and `{autoUpdate:"auto"}` installs it by itself. Restart Claude to finish.

* **New command: `nativecad-impactdiff`** (CADSF-100738, CADSF-100742). What a board revision did to the board, as impactDiff v1 JSON, with no agent in the loop: for a git hook, a CI step, or a server that runs once per commit.
  * Two board files (`--before` / `--after`), or two commits of a repo (`--repo --before-ref --after-ref --path`, read with git plumbing, no checkout).
  * `--batch jobs.jsonl` runs many pairs through one engine, one result line per job.
  * `--targets file.json` passes the project's own limits (impedance classes, rails, power, IPC class / fab / creepage pairs, stackup, return path, ambient), so impacts are judged against them. Unknown keys are refused.
  * Offline by default: telemetry and auto-update off; with `CADSOLVER_FLEET_TOKEN` the engine runs in worker mode and the licence is never written to disk.
  * Exit codes: 0 ok, 1 an impact at or above `--fail-on`, 2 usage, 3 licence required, 4 refusal or engine error. Deterministic output.
  * Needs nothing from node_modules: install with `npm install -g https://featureboard.ai/nativecad/releases/nativecad-mcp-0.18.3.tgz`, or on an air-gapped box unpack the `.tgz` and run `node package/bin/nativecad-impactdiff.js`.

## Gates

* **bundle-smoke over stdio, on the shipped `.mcpb` and `.plugin`.** tools/list 170; staged git `47d6c023`, tree `d2fe536e005b`, 653 files.
* **Features:** MCP e2e cadsf-100738 (25 from source; 23 against the bundle), cadsf-100025 (43), package (277), cadsf-1662 (19), schema-sync (572), tool-list-budget (32). The shipped `.tgz`, unpacked with no node_modules: a two-pair `--batch` and the unlicensed exit 3.

**Downloads:** https://featureboard.ai/nativecad/releases/nativecad-mcp-0.18.3.mcpb and https://featureboard.ai/nativecad/releases/nativecad-mcp-0.18.3.tgz (`latest.json` lists bytes, sha256 and the ed25519 signature, key `d2791510af4077e7`).

**Build.** Built from `ticket/CADSF-100742` `47d6c023` (parent: master `989db2aa`), with `SOURCE_DATE_EPOCH` set to 1791159424. `dist/server.min.js` (sha256 `0f62aa5b…`) is identical in the `.tgz`, the `.mcpb` and the `.plugin`.