# Clusters unique per cluster

**🟡 Intermediate · Lesson 25**

Clusters - named groups of dynamic conduits that AUTO-SHARE cluster-scoped spells. unique_per_conduit_cluster finally comes alive: one instance per cluster, shared by every member. (This completes the declaration parked in the expert tier's example 01.)

## Before you run

Use the [Intermediate guide](../../intermediate/index.md) for prerequisite concepts. Run from a checkout with Melder installed and Python 3.14 free-threading selected. The collection download includes the level's local helper modules.

## Run the saved script

```bash
python UX_and_AIX_experiences/02_intermediate/25_clusters_unique_per_cluster.py
```

```powershell
py -3.14t UX_and_AIX_experiences/02_intermediate/25_clusters_unique_per_cluster.py
```

{download}`Download this collection <../../downloads/intermediate-examples.zip>` · [Source on GitHub](https://github.com/Synaptic724/melder/blob/1211e838099a342c9dde48f064b1e772b6060e13/UX_and_AIX_experiences/02_intermediate/25_clusters_unique_per_cluster.py)

## Public surface

create_cluster, add_conduit_to_cluster,
                   existence="unique_per_conduit_cluster"

## Code

```{literalinclude} ../../downloads/02_intermediate/25_clusters_unique_per_cluster.py
:language: python
:linenos:
```

## Check the outcome

The script contains its own assertions or demonstrated refusal paths. Run it to evaluate those checks against your installed version. The code above is taken directly from the saved file; no run output is invented here.

[More intermediate examples](index.md) · [Level guide](../../intermediate/index.md)

## Related guides

- [Connected subsystem walkthrough](../../intermediate/connected-subsystems.md)
- [Conduit clusters](../../advanced/clusters.md)