Add minimum purchase condition for automatic promotions (with optional auto-add product)

[aroard]

I would like to propose an enhancement to the promotion system by introducing a minimum purchase requirement for automatic promotions.

Currently, automatic promotions can apply directly without a minimum cart threshold. The proposed feature would allow store owners to define a minimum purchase amount that must be reached before the promotion is activated.

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Use Case

Example:
• Promotion: Free Product X
• Condition: Minimum cart total of 100€
• Behavior:
• If cart total < 100€ → promotion does not apply
• If cart total ≥ 100€ → promotion automatically activates

Additionally:

If the promotion grants a specific product, the product would be automatically added to the cart when the minimum purchase is reached.

This ensures:
• Clear UX
• Fully automatic promotional flow
• No manual coupon entry required

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Extended Behavior

This logic would apply to:
• Automatic free product promotions
• Automatic percentage or fixed discounts (only activated once the minimum purchase is reached)

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Proposed Implementation Idea

High-level idea:
• Extend the promotion configuration with:
• minimum_purchase_amount
• Validate threshold during cart total calculation
• If condition is met:
• Apply discount
• Or automatically insert the promotional product into the cart

The promotion would deactivate automatically if the cart total drops below the threshold.

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Real-World Implementation

I have implemented this logic in my own Medusa backend and it works very well in production.

When a customer adds items to the cart:
• If the minimum purchase is reached, the promotion applies automatically.
• If the promotion is product-based, the product is automatically inserted.
• If the cart drops below the threshold, the promotion is removed.

This has been extremely practical from a business and UX perspective.

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Question

Would this be something aligned with Medusa’s promotion roadmap?

If useful, I can:
• Share implementation details
• Open a draft PR
• Refactor my implementation to match core architecture standards

Regarding sharing a live commercial site for testing: I’m not sure if that’s appropriate, but I could instead provide:
• A short demo video
• A minimal reproduction example
• Or a test branch

I’d be happy to contribute this feature properly to the core if there is interest.