The project intentionally stays dependency-light while demonstrating product UX, browser storage, deterministic money calculations, accessible UI patterns, testing and static deployment.
Semantic HTML provides the UI, CSS provides the design system, app.js owns state and UI orchestration, and settlement.js contains the isolated finance engine.
Browser UI
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app.js — state + events
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settlement.js — deterministic calculations
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localStorage — workspace persistenceThe problem does not require a framework. Keeping the application native makes the state model visible, reduces bundle size and lets the repository demonstrate fundamentals rather than dependency management.
Amounts are stored as integer minor units to avoid common floating-point money errors.
Members and expenses live inside named workspaces instead of one global session object.
Each expense records who shared it, so a WiFi bill and a dinner can involve different people.
The test suite covers equal splits, participant-specific expenses, paise remainders, multi-expense balances and deterministic transfer output.
npm testFor the browser app, open the static site through a local web server so ES modules resolve correctly.
The repository includes a GitHub Actions workflow that runs syntax and settlement checks on pushes and pull requests. GitHub Pages can then serve the static site from the repository.