EM-RTL-04 · Subject model · W-IND
Basket, checkout and sales transaction
An online basket or a store basket, the checkout that turns it into a sale, and the completed sales transaction with lines, applied prices, tenders, receipt and voids. Customer orders for later fulfilment and invoices are separate contours.
Partially published; research continues
Claude: initial-industry-contour-and-card-supplement; Grok: not-started.
Published results
The independent second-provider study, fixtures and the full research protocol remain open. Runtime promotion is governed by the package allocation holds.
Subject boundary and candidate types
- Basket
- BasketLine
- CheckoutSession
- SalesTransaction
- TenderLine
- Receipt
- VoidRecord
Deep research questions
- When does a basket become a sale and when a customer order for later fulfilment?
- How are voids recorded without deleting the transaction?
- How are tenders split across payment methods and gift cards?
Verifiable invariants
- A completed transaction balances: lines, adjustments and taxes equal the tenders
- A void is a new record that references the original
- Each transaction references its selling location, device and operator
End-to-end acceptance scenario
For a synthetic store and web shop, complete one cash and one card sale, void one line, abandon one basket, turn one checkout into a click and collect order, and show the balanced transaction records.
Negative case
Abandoned baskets are counted as sales, and stock is reserved for days for baskets that will never be paid.
Approaches to compare
- ARTS standards (OMG): POSLog for point of sale transactions
- schema.org: Order, BuyAction and Offer
- W3C Payment Request API: checkout payment interface
Candidates in the live catalogue
- WM-ECO-020 · Sales Order · 0.3.0-research.1 · installable
Semantic fit requires boundary research; a published model does not by itself complete this card. - WM-ECO-009 · Payment · 0.3.0-research.1 · installable
Semantic fit requires boundary research; a published model does not by itself complete this card. - WM-ECO-008 · Invoice / Commercial Document · 0.3.0-research.1 · installable
Semantic fit requires boundary research; a published model does not by itself complete this card.
Result requirements
Every card is executed together with the full research contract: definitions, fields and cardinalities, lifecycle, sources, data mastership, rights, the five object facets, at least eight invariants, positive and negative examples, dependencies, migration and applicability limits.