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

# Callbacks

> systematica.tuners.optuna_.callbacks

## `OptunaLoggingCallback`

```python theme={null}
OptunaLoggingCallback(
    update_interval: int = 1,
    timer: object = None,
)
```

Lightweight Optuna callback that displays trials in a Rich table.
Works with both single and multi-objective optimization.

**Parameters**:

| Name              | Type     | Default | Description                                            |
| ----------------- | -------- | ------- | ------------------------------------------------------ |
| `update_interval` | `int`    | `--`    | Update table every N trials (default: 1)               |
| `timer`           | `object` | `--`    | Timer object with elapsed() method (e.g., vbt.Timer()) |