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Somnath Das
Somnath Das

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Bill Buddy

#devchallenge #hf26challenge

Hacktoberfest Open-Source AI Challenge Week 2: Side Hustle Submission 💸

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

BillBuddy 🧾⚡ — Private, Intelligent Invoicing for Side Hustles

What I Built

BillBuddy is a zero-leakage, local billing app for freelancers, consultants, and side hustlers who want professional invoicing without $15–$50/mo SaaS subscriptions or data privacy risks.

  • Fast Invoicing: Multi-currency ($, ₹, €, £, etc.), auto-numbering, live calculations, and clean A4 PDF export across 4 sleek templates.
  • AI Smart Draft: Generate complete structured invoices from natural language prompts (e.g., "Bill Acme Corp for 20h dev at $90/hr + $250 setup, 8% tax").
  • AI Financial Auditor: Evaluates profit margins, payment delay risks, tax compliance, and drafts client delivery emails.
  • Zero Data Leakage: Sensitive rates and client lists never leave your machine.

Demo

Watch the Demo

  • Local App: http://localhost:3000 (runs locally via npm start)
  • Key Flow: Edit in real time → Auto-generate via prompt → Audit with local AI → Export vector A4 PDF.

Code

GitHub logo somnathdas9733 / BillBuddy

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

BillBuddy 🧾⚡ — Private, Intelligent Invoicing for Modern Side Hustles & Businesses

What I Built

BillBuddy is a zero-leakage, high-performance billing and invoicing application designed specifically for freelancers, boutique agencies, consultants, and side hustlers.

What does it do?

  • Intuitive Invoice Creation: Complete business profile (name, logo, tax/GST/VAT ID, address), client details, auto-generated invoice numbers, custom currencies ($, ₹, €, £, A$, C$, Â¥), and dynamic line items with real-time tax, discounts, and totals calculation.
  • Easy Download as PDF for Customer: One-click, high-resolution A4 PDF download formatted specifically for clients, plus dedicated @media print zero-margin print mode.
  • 4 Professional Invoice Templates: Switch instantly between Modern Minimalist, Executive Navy, Emerald Luxe, and Monochrome Tech.
  • AI Smart Draft (Prompt to Invoice): Users can…
View on GitHub
  • Frontend: Vanilla JS (ES6+), Semantic HTML5, bespoke responsive CSS (@media print support).
  • Export & Parsing: html2pdf.js, marked.js.
  • Backend: Node.js & Express local proxy.
  • AI Engine: Local Gemma 4 (gemma4:latest, 7.5B) running on Ollama.

How I Built It

BillBuddy connects to Google's Gemma 4 on-device via Ollama (http://127.0.0.1:11434):

  1. Prompt-to-Invoice (/api/ollama/parse-prompt): Gemma 4 parses freeform text into a strict JSON schema to auto-populate invoice line items.
  2. CFO Financial Audit (/api/ollama/analyze-invoice): Audits invoice metadata for health score (1–10), cash-flow/payment risk, tax readiness, upsell opportunities, and a copy-paste client email.
  3. Local Q&A Assistant: In-app advisory for negotiation tips and payment term strategy.

Why Does Open Innovation Matter?

  • Financial Privacy: Invoicing data and client lists remain 100% on-device instead of third-party cloud servers.
  • Zero Token Cost: Unlimited drafts and financial audits with zero API fees or subscription tiers.
  • Offline Autonomy: Fully operational offline or in low-connectivity environments.

My Agent Session

Built using **Antigravity* (Google DeepMind agentic coding assistant) to generate and verify the app architecture, Ollama proxy, PDF exporter, and prompt pipelines end-to-end.*

Prize Categories

  • Side Hustle Track
  • Local Inference / Best Use of Open-Weight Models
  • Open-Source AI Innovation

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