0005. Accounting systems behind a plugin interface

Status	Accepted
Date	2026-10-10
Deciders	Stuart Meeks

Context

The design partner shop is believed to use Xero. Other shops use MYOB, QuickBooks or others. Coupling invoicing directly to one provider would make Signboard unusable for most shops.

Decision

We will define an accounting interface covering contacts, invoices and payments, and implement Xero as the first provider. Signboard's invoicing works without any provider configured.

Consequences

• Other providers can be contributed without touching core invoicing.
• The interface must be designed around the common denominator of providers, not Xero's specifics.