Raj Gajjar

AutoInvoice: GST invoicing for small businesses

An invoicing app for small businesses: create GST invoices, delivery challans, and proformas, then send them as PDFs over email or WhatsApp.

2026Full-stack
FastAPIReactPostgreSQLRedisAWS LambdaCloudflare Workers
UnifiedDesk landing page — GST invoicing made effortless for your business, with an illustration of a shop owner at a desk
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A billing workspace for small Indian businesses. Set up your company once, keep customers and inventory on file, and turn out invoices, delivery challans, and proformas from reusable templates. Each one renders as a PDF and goes straight to the customer by email or WhatsApp. It’s now live as UnifiedDesk.

What it does

  • Invoices built for GST: HSN/SAC codes filled in from inventory, tax and discount per line item, round-off, and the amount in words using Indian numbering (lakhs and crores).
  • More than invoices: delivery challans and proformas use the same templates and line items.
  • Sending: PDF generation, then delivery by Gmail or WhatsApp, with a compose window and a searchable customer picker.
  • Data tables: build your own tables with configurable columns, reminders, and export.
  • Accounts: email/password or Google sign-in. Claims-based JWTs live in cookies, so routes scoped to one owner skip a database lookup.

Security and ops

Bank details are encrypted at rest with AES-256-GCM and masked in the UI. Rate limiting runs on Redis, with an in-memory fallback if Redis can’t be reached. Every response carries security headers, and each log line from structlog includes the request ID. CI runs lint, type checks, mock tests, and integration tests against real Postgres and Redis.

Deploy

The FastAPI backend runs as a container on AWS Lambda behind Mangum, using Supabase Postgres and Upstash Redis. The React frontend runs on Cloudflare Workers. The Worker also proxies /api so the auth cookies count as first-party. Without that, Safari’s tracking protection dropped the cross-site cookies from the Lambda URL, and iOS users kept getting sent back to the login page.