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# knut's own quality matrix (L4b)
knut consumes the published reusable test-matrix engine
[`nornir-testmatrix`](https://crates.io/crates/nornir-testmatrix) as a
**dev-dependency** of the `knut-bifrost` member (the crate that already hosts
the file→graph lifecycle integration tests). This proves the matrix framework
is reusable from this repo — knut can render its OWN quality matrix
standalone, with no nornir checkout.
## Run knut's matrix
```sh
cargo run -p knut-bifrost --example quality_matrix
```
This runs `run_full_matrix(".", Aspect::DEFAULT)` — build, unit, doctest,
clippy, fmt, audit — writes the rows to `target/quality-matrix.jsonl` via
`JsonFileSink`, and prints `render_matrix(&rows)`.
It shells one `cargo` invocation per aspect, so it is **deliberately NOT** in
the normal `cargo test` path (no cargo-inside-cargo on every test run).
## Wiring proof (fast + offline)
`crates/knut-bifrost/tests/testmatrix_wiring.rs` is an inject-and-assert test
(`testmatrix_roundtrip_and_render_inject_assert`): it feeds canned
`TestResultRow`s (varied status / aspect / metric) through the real
`JsonFileSink` round-trip and `summarize_runs` + `render_matrix`, then asserts
exact tallies, that aspect+metric survive serde, and that the rendered grid
shows the red `✗` marker. No cargo subprocess, no network.