VoiceyBill — Backend

REST API powering transaction management, voice-to-transaction AI processing, receipt scanning, report scheduling, and user auth for VoiceyBill.

Tech stack

• Express 4 + TypeScript
• MongoDB via Mongoose 8
• Passport.js + JWT for authentication
• Google Generative AI (Gemini) for voice transcription classification
• OpenAI for receipt scanning
• Cloudinary for file/image storage
• Resend for transactional email (report delivery)
• node-cron for scheduled report jobs

Prerequisites

• Node.js 20 or later
• MongoDB instance (local or Atlas)

Setup

cp .env.example .env   # fill in required values
npm ci

Environment variables

Variable	Description
PORT	Server port (default 5000)
MONGO_URI	MongoDB connection string
JWT_SECRET	Secret for signing JWT tokens
CLOUDINARY_CLOUD_NAME	Cloudinary cloud name
CLOUDINARY_API_KEY	Cloudinary API key
CLOUDINARY_API_SECRET	Cloudinary API secret
GEMINI_API_KEY	Google Generative AI key (voice processing)
OPENAI_API_KEY	OpenAI key (receipt scanning)
RESEND_API_KEY	Resend API key (report emails)
CLIENT_URL	Allowed CORS origin for the web client

Development

npm run dev     # ts-node-dev with hot reload
npm run build   # compile TypeScript → dist/
npm start       # run compiled build

API areas

• Auth — register, login, JWT refresh
• Transactions — CRUD, bulk delete, CSV import, duplicate, recurring intervals
• Analytics — dashboard stats, income/expense trends, category breakdown
• Voice — upload audio, AI transcription → structured transaction data
• Receipt scan — upload receipt image, AI extraction → transaction fields
• Reports — generate reports, schedule recurring email delivery
• User — profile update, avatar upload

Contributing

See CONTRIBUTING.md, CODE_OF_CONDUCT.md, and SECURITY.md.