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type: reference
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# Contracts

Part of **Project Yukart**, making an old 2008 Mitsubishi Z27AG a bit smarter with modern technologies.  
This file serves as the minimalist portal to other docs


## What this repo is about

The topic namespace, payload schemas and signal registry that every other repo
depends on. Rust services, Python tooling and the Dart client all read the same
definitions from here.

| File | Holds |
|---|---|
| [`schema/topics.json`](schema/topics.json) | Topic namespace: payload kind, retention, rate, publisher |
| [`schema/envelope.json`](schema/envelope.json) | JSON Schema for the decoded-signal envelope |
| [`schema/signals.json`](schema/signals.json) | Signal registry — the single source for name, unit, type and range |
| [`docs/BOUNDARY.md`](docs/BOUNDARY.md) | Display boundary protocol: what crosses between `svc-gw` and the app |
| [`checklists/`](checklists/) | Recording checklists as data; the app bundles exact copies (its **Captures** page) |

The Z27AG DBC lands here too, once Phase 2 produces one.

- For implementation practice guidelines, refer to the [guidelines](docs/GUIDELINES.md);  
- For implementation plans and history, refer to [them](docs/impl/);