Overview ​
SudoSOS is GEWIS’ point-of-sale and internal financial system. It records purchases, deposits, invoices, payouts, and the audit trail around them. This repository contains the backend API that enforces the rules.
After reading this page, you should know what SudoSOS is for, who uses it, and which terms show up throughout the docs.
Looking for API details?
- Swagger API:
https://sudosos.gewis.nl/api/api-docs/ - TypeDoc:
/typedoc/
What SudoSOS is ​
At its core, SudoSOS does two things:
- Point of sale: fast purchases at borrels and activities (self-service or cashier-driven).
- Ledger and settlement: track who owes what, generate invoices, and process deposits and payouts.
It integrates with GEWIS organisational data so that members, organs, and roles do not need to be managed twice.
Who uses it ​
- Members: buy items, top up, view their history.
- Cashiers: enter purchases for members.
- Organs/committees: act as sellers; manage products and points of sale.
- Finance/admin: generate invoices, handle exceptions, approve payouts, and report.
What the backend owns ​
- Authoritative business rules: validation, pricing rules via revisions, debt limits.
- Audit trail: transactions, transfers, invoices, and balance snapshots.
- Authorisation: role-based access control (RBAC).
- Integrations: sync of users/roles, Stripe deposit entry points, and mail notifications.
The backend does not provide a user interface. The dashboard and POS UI live in the separate frontend repository.
Frontend code
The dashboard and POS UI are in https://github.com/GEWIS/sudosos-frontend.
Terms you will see everywhere ​
- Transaction: a purchase event (one buyer, one or more sellers).
- Transfer: money movement that is not a purchase (deposit, payout, invoice, fine, write-off).
- Balance: cached snapshot derived from transactions and transfers. We treat balance as a multi-purpose voucher (MPV), which is the basis for our VAT reasoning (see Directive (EU) 2016/1065).
- Invoice: groups outstanding purchases for settlement.
- Revision: historical snapshot of product/container/POS configuration.
- Point of sale (POS): where purchases happen (and how permissions/config are scoped).
- Container: a group of products of a single seller shown together at a POS (e.g. fridge, bar).