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ROSSWEISSE KAS

A multi-user shared-fund bookkeeping app for small groups, with role-based access and realtime sync across devices.

CATEGORY
Web2 /Finance /Realtime
ROLE Independent Developer
STATUS
COMPLETED
YEAR 2026
ReactViteTypeScriptSupabasePostgreSQLFramer MotionLucide React

DEMO VIDEO

R DEMO VIDEO IN PREPARATION
00:45

OVERVIEW


Rossweisse Fund is a multi-user web application for recording a shared cash fund inside a small group. It runs on a Supabase backend with an online PostgreSQL database: an admin manages the fund while members can see the balance and their own payment status, and every change propagates to all connected devices in realtime. The earlier localStorage-only version was replaced by the hosted backend so the data is no longer trapped on a single browser.

PROBLEM


Small groups usually track a shared fund in a spreadsheet or a chat thread. Only one person holds the real numbers, members cannot verify their own payment status, and there is no audit trail when a figure changes.

SOLUTION


A role-separated web app on Supabase where the admin records payments and expenses while members get read-only visibility into the balance, their status, and the full history. Postgres row-level security enforces the role boundary, and realtime subscriptions keep every device in sync.

CORE FEATURES


  • Email auth with automatic admin assignment for the first account
  • Dashboard for balance, total income, and total expenses
  • Member management: add, edit, deactivate
  • Monthly fund periods with per-member payment status (paid, partial, unpaid)
  • Expense recording with categories
  • Transaction history plus an audit log visible to everyone
  • Period reports with WhatsApp sharing
  • JSON backup export and import
  • Realtime sync across devices

TECHNICAL CHALLENGES


  • Enforcing the admin/member split at the database level with RLS instead of trusting the client
  • Migrating an existing localStorage data model onto a hosted Postgres schema without losing records

ROLE & CONTRIBUTION


Full-stack application development

Supabase schema and row-level security policies

Auth and role model (first account becomes admin)

Realtime data store and state layer

TECHNOLOGY STACK


ReactViteTypeScriptSupabasePostgreSQLFramer MotionLucide React