BillBuddy

This is a submission for the Hacktoberfest Open-Source AI Challenge Week 2: Side Hustle

What I Built

Meet BillBuddy, a personal finance web app designed to make expense tracking and budgeting simpler.

It is easy to lose track of small expenses throughout the month. BillBuddy brings transactions, budgets, and spending insights together in one place so users can understand where their money goes and make more informed financial decisions.

Demo

https://bill-buddy-2jck0jz8l-riya-rathis-projects.vercel.app/

Code

https://github.com/riyarathi2211/billBuddy

How I Built It

I built BillBuddy using React and Vite, with a focus on a clean interface and a practical, responsive user experience.

I organized the application into separate pages for the Dashboard, Documents, Budgets, Insights, Categories, and Export. This keeps the interface easy to navigate without overcrowding a single screen.

Transactions are stored in IndexedDB, while budget settings are persisted in localStorage. Spending summaries, budget alerts, unusual-expense flags, and monthly forecasts are calculated from the available transaction history.

Receipt scanning uses OCR to help extract text from uploaded receipts.

AI and open-source model disclosure: The current Smart Insights functionality uses locally calculated rules and spending statistics. These features should not be described as generative AI unless an open-source AI model is actually integrated into the application.

For this challenge, I would like to explore how open-weight models and local inference could further improve expense categorization, receipt understanding, and personalized financial recommendations without depending on a paid, closed AI API.

Why Does Open Innovation Matter?

My Agent Session

Open innovation makes it easier for developers to experiment, learn from existing tools, and build useful applications without having to create every component from scratch.

For a personal finance tool like BillBuddy, open-source libraries make features such as OCR, data visualization, and browser-side persistence more accessible.

It also creates opportunities to experiment with open-weight AI models that can potentially run locally. This could reduce dependence on external services, improve user control over financial data, and make intelligent features more accessible to people with limited budgets.

For me, open innovation is about making useful technology more accessible while giving developers the freedom to learn, customize, and improve it.