# Last Tuesday Stripe added an optional discount field

Canonical URL: <https://datadriven.io/problems/last-tuesday-stripe-added-an-optional-discount-field-by-wed-adbb8256>

Domain: Pipeline Design · Difficulty: medium

## Problem

Last Tuesday Stripe added an optional discount field. By Wednesday morning the curated fct_orders table silently double-counted discounts; three downstream teams discovered the breakage at different times because nobody was monitoring fct_orders. Apply the section's pipelines-as-products framing and declare the contract for fct_orders so the next schema drift is caught before consumers see broken data.

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