# Spell override construction

**🟡 Intermediate · Lesson 08**

Two honest ways to construct with configuration: a factory that closes over its config (bind-site), and override at meld - a FLAT dict of keyword overrides for the melded spell's OWN constructor. Simple and top-level on purpose; targeting objects DEEPER in the graph is an advanced-tier lesson. (bind(**kwargs) is a different channel entirely: it lands on spell.metadata - lesson 06.)

## 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/08_spell_override_construction.py
```

```powershell
py -3.14t UX_and_AIX_experiences/02_intermediate/08_spell_override_construction.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/08_spell_override_construction.py)

## Public surface

factory spells, meld(override={...})

## Code

```{literalinclude} ../../downloads/02_intermediate/08_spell_override_construction.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

- [Flat overrides and live probes](../../intermediate/overrides.md)