saleor Saleor Core
Backend behavior reference derived from the Saleor core source code. Covers internal mechanics that aren't fully documented in the public API reference — discount precedence, stock availability modes, denormalized fields, and known Dashboard gotchas.
When to Apply
- Building or debugging discount/promotion UI in the Dashboard
- Investigating why a voucher or promotion isn't applying
- Understanding order-level vs line-level discount precedence
- Working with
OrderDiscount/OrderLineDiscountobjects - Debugging
unit_discount_valueonOrderLine - Deciding whether discounts stack or suppress each other
- Building price-explanation / waterfall tooling on confirmed orders
- Reconstructing how an order-level discount distributed across lines
- Handling free-gift order lines (
OrderLine.isGift = true) - Working on stock availability, shipping zones, warehouses, or
Shop.useLegacyShippingZoneStockAvailability - Debugging why
PRODUCT_VARIANT_*_IN_CHANNELwebhooks aren't firing - Building diagnostic / "doctor" tooling that explains availability problems
- Auditing Dashboard copy that uses "available" / "in stock" / "purchasable"
Rule Categories
| Priority | Category | Impact | Prefix |
|---|---|---|---|
| 1 | Discounts | CRITICAL | discount- |
| 2 | Stock | CRITICAL | stock- |
Quick Reference
1. Discounts (CRITICAL)
discount-precedence— Full precedence hierarchy, stacking rules, manual vs voucher vs promotion interactions, denormalized field semantics, known Dashboard bugorder-discount-allocation— Two-pass calculation of order-level discounts (Pass A collapses records into a single subtotal_discount; Pass B distributes proportionally across lines with last-line absorbing rounding), what the API exposes (per-line totals, per-record-at-order amounts) and what it doesn't (per-record-per-line decomposition), gift-line shape gotcha (ORDER_PROMOTIONonOrderLine.discounts[]whenisGift = true), reconstruction guidance for consumers
2. Stock (CRITICAL)
stock-availability-modes—Shop.useLegacyShippingZoneStockAvailability(3.23+), purchasability vs shippability, server queryset dispatch, mode-conditional webhooks, Dashboard UI / copy / severity rules, migration footguns, test fixtures
How to Use
Read individual rule files for detailed explanations and source-level evidence:
rules/discount-precedence.md
rules/order-discount-allocation.md
rules/stock-availability-modes.md
Each rule file contains:
- Precedence hierarchy or computation rules
- Source code references from
saleor/with function names and file paths - Anti-patterns and known bugs