# Utility system logger

**🟠 Advanced · Lesson 04**

Logging through the AetherUtilitySystem - the process-wide provider host every runtime object resolves its logger from. THE BOOT LAW: melder boots SILENT. Aether starts with a null SafeLogger and stays quiet until YOU attach something - no surprise stdout, no library spam. Two public doors: aether.attach_logger(logger) - attach one real logger (stdlib Logger or channel-style), or None to detach back to silence aether.enable_logging(logger) - attach explicitly, or with no argument try the configured automatic channel-logger policy Runtime objects (books, conduits, the frames themselves) resolve their loggers through the utility system's provider path.

## Before you run

Use the [Advanced guide](../../advanced/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/03_advanced/04_utility_system_logger.py
```

```powershell
py -3.14t UX_and_AIX_experiences/03_advanced/04_utility_system_logger.py
```

{download}`Download this collection <../../downloads/advanced-examples.zip>` · [Source on GitHub](https://github.com/Synaptic724/melder/blob/a30a754d0bb61db0b142936010cdb82cffecec6f/UX_and_AIX_experiences/03_advanced/04_utility_system_logger.py)

## Public surface

md.Aether().attach_logger, enable_logging,
                   the boots-silent law

## Code

```{literalinclude} ../../downloads/03_advanced/04_utility_system_logger.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 advanced examples](index.md) · [Level guide](../../advanced/index.md)

## Related guides

- [Explicit logging setup](../../advanced/logging.md)

## API contracts

- [Aether](../../reference/api/configuration/aether.md)