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

# Lumin Discount App

> Apply mix and match bundle discounts at checkout

# Lumin Discount App

The theme’s mix & match UI shows tier messaging in the storefront. **Checkout discounts** are applied by the **Lumin Discount App**. Without it, customers may see “X% off” in the builder while paying full price.

## Video

```html theme={null}
<iframe
  src="https://www.loom.com/embed/VIDEO_ID"
  frameborder="0"
  allowFullScreen
  style="width: 100%; height: 400px; border-radius: 8px;"
></iframe>
```

## When you need it

* You use [Mix and match bundles](https://docs.lumintheme.com/guides/mix-and-match-bundles.md)
* You need automatic percentage (or tier) discounts based on bundle cart properties

## Setup checklist

1. Install **Lumin Discount App** from your Lumintheme distribution channel.
2. Open the app and enable discounts for LuminOS mix & match / `_lumin_bundle_*` line properties.
3. Align tier percents in the app with the percentages shown in the Bundle Builder section.
4. Place a test order (development store) and confirm the discount line appears at checkout.

## Related

* [Mix and match bundles](https://docs.lumintheme.com/guides/mix-and-match-bundles.md)
* [Cart drawer](https://docs.lumintheme.com/guides/cart-drawer.md)
* [Troubleshooting](https://docs.lumintheme.com/troubleshooting/common-issues.md)

## Still stuck?

Post in [Bugs](https://community.lumintheme.com/c/bugs) if the app is installed but checkout ignores tiers—include app version and a cart screenshot.


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