payment-flow-architecture

name	payment-flow-architecture
description	Architect money-safe payments: represent money as integer minor units + currency (never floats), keep a double-entry append-only ledger as source of truth (the PSP is an integration you reconcile against), design a money-event model, and reconcile continuously.

Payment Flow Architecture

Money = integers

Integer minor units (cents) + currency code. Never floats — float money = rounding-error disputes.

Double-entry ledger = source of truth

Every movement = balanced debits/credits in an append-only ledger you own. The PSP is an integration you reconcile against, not your books.

Reconcile continuously

Match ledger to PSP (payouts/fees/disputes); a discrepancy is a bug or fraud, not rounding. Unreconciled = mystery money.

Hand off

Money events here; revenue recognition/GL -> finance; regulation -> regulatory-compliance.