> ## Documentation Index
> Fetch the complete documentation index at: https://ctrlrun.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# run

> Drive every case against `backend` and report what each came to (SPEC-v0.6 §2).

`ctrlrun.conformance.store.run` — function, defined at `src/ctrlrun/conformance/store/__init__.py:52`

```python theme={null}
from ctrlrun.conformance.store import run
```

Needs the `conformance` extra: `pip install "ctrlrun[conformance]"`. Importing it without that raises `MissingDependency` carrying the install command.

```python theme={null}
def run(backend: StoreBackend, *, only: Sequence[str] = (), processes: int = CONTENDERS) -> StoreReport
```

Drive every case against `backend` and report what each came to (SPEC-v0.6 §2).

`only` selects case ids; an unknown name **raises** rather than silently running everything
or nothing. It is a keyword and not a CLI flag -- §9.4 adds no command, so there is nothing
for an unknown name to exit from.

`processes` is how many contenders the two E1 cases run, in threads and in OS processes
respectively. It is `v0.1 §7` T3's eight by default. A review found it named in §2.4, §9.1
and T143 while the code used a module constant, so the parameter that the specification
freezes did not exist.

Every case gets a freshly `reset()` backend, so no case can see another's rows. A case that
raises out of its own body is reported as a failed case naming the exception, never as a
crashed run: one broken case must not hide the twenty that worked.

## Next

* [Python API index](/reference/api/index).
* [Get started](/get-started/quickstart) · [Why](/why).


## Related topics

- [run](/reference/api/verify-run.md)
- [Run it in production](/production/index.md)
- [CTRLRun](/index.md)
- [Run on Postgres](/guides/run-on-postgres.md)