JustSplit¶

Fair expense sharing made simple.

JustSplit is CyberEco's expense sharing application for groups, roommates, trips, and social events. It was the first application in the CyberEco ecosystem and serves as the proving ground for the shared data layer architecture.

Status: Live Application

JustSplit is available now at justsplit.cybere.co

What It Does¶

JustSplit takes the friction out of shared expenses. Whether you are splitting rent with roommates, tracking costs on a group trip, or managing household expenses with a partner, JustSplit handles the math and keeps everyone informed.

Core Features¶

Feature	Description
Group Management	Create and manage expense groups for any occasion -- trips, households, events, or ongoing shared costs
Expense Tracking	Log expenses with descriptions, amounts, dates, and custom split ratios. Multiple currency support included
Smart Splitting	Flexible split options: equal, percentage-based, exact amounts, or custom shares. The algorithm calculates who owes what
Settlement Suggestions	Optimized settlement paths that minimize the number of transactions needed to balance all debts
Real-time Sync	Changes sync instantly across all group members. Everyone sees the same balances at the same time
Balance Dashboard	Clear visualization of who owes whom, with running totals and transaction history

Part of the CyberEco Ecosystem¶

JustSplit is not a standalone app -- it is a first-class member of the CyberEco ecosystem. This means it benefits from shared infrastructure and interoperates with other CyberEco applications.

Single Sign-On¶

Users sign in once through the CyberEco Hub and are automatically authenticated in JustSplit. No separate account required, no extra password to remember.

Shared Data Layer¶

JustSplit is built on the same @cyber-eco/services data layer that powers every CyberEco application. This means:

Groups created in JustSplit are visible across the ecosystem (with appropriate permissions)
User profiles are managed centrally through the Hub
Financial data can flow to other CyberEco apps (like MyWealth) when the user grants permission
Notifications are delivered through the unified CyberEco notification system

Privacy Controls¶

JustSplit respects the privacy settings configured in the Hub. Users control exactly what data is shared, with whom, and for how long.

Technical Architecture¶

JustSplit demonstrates the power of the CyberEco data layer in a production application.

Built With the CyberEco Data Layer¶

import { createDataLayer } from '@cyber-eco/services';
import { FirebaseStorageAdapter } from '@cyber-eco/firebase';

// JustSplit uses the same data layer as every CyberEco app
const dataLayer = createDataLayer(adapter);

// Expense operations go through the orchestrator
await dataLayer.create('expenses', {
  groupId: 'trip-2025',
  amount: 120.00,
  description: 'Dinner at restaurant',
  paidBy: 'user123',
  splitBetween: ['user123', 'user456', 'user789'],
  splitType: 'equal',
});

Key Technical Details¶

Aspect	Detail
Data Layer	`@cyber-eco/services` with `FirebaseStorageAdapter`
Authentication	Firebase Auth via `@cyber-eco/auth`, SSO with Hub
Real-time Sync	Firestore real-time listeners through `DataLayerService`
Permissions	4-tier role hierarchy (owner/admin/moderator/member)
Offline Support	IndexedDB persistence via `FirebaseStorageAdapter`
Caching	Multi-level cache (L1 in-memory + L2 optional)

StorageAdapter Benefit¶

Because JustSplit uses the StorageAdapter interface (not Firebase directly), the entire application can be migrated to a different storage backend -- IPFS, a blockchain, or a peer-to-peer mesh -- without changing any business logic. The expense splitting algorithms, settlement calculations, and group management code remain identical regardless of where data lives.

Feature Roadmap¶

Planned enhancements for JustSplit within the CyberEco ecosystem.

Feature	Timeline	Description
Marketplace integration	2025-2026	Split payments for Marketplace purchases directly within JustSplit
Receipt scanning	2026	OCR-powered receipt scanning to auto-fill expense details
Recurring expenses	2026	Automated tracking for regular shared costs (rent, utilities)
P2P settlement	2027+	Direct peer-to-peer payments via CYE token
Encrypted expenses	2027+	Client-side encryption for sensitive financial data

Getting Started¶

As a UserAs a Developer

Create an account at hub.cybere.co
Navigate to justsplit.cybere.co
Create a group and invite your friends
Start logging expenses

Clone the monorepo: git clone https://github.com/cyber-eco/cybereco-hub.git
Install dependencies: npm ci
Build the data layer: npm run build
Explore JustSplit's use of @cyber-eco/services as a reference implementation

Try JustSplit View Solutions Overview