Full-Stack: Shipping Label Web App (Crypto Payments)
The Gist:
I need a robust, bug-free web app that acts as a simplified version of ShipStation.
Tech Stack: Node.js or Python Backend (NO PHP). React/Next.js Frontend.
Payment: 100% USDT via Escrow.
The Flow:
User: Signs up (Email/Pass, NO email verification needed) \(\to\) Logs in.
Wallet: User clicks "Add Funds" \(\to\) Redirects to Crypto Gateway (e.g., NowPayments/BTCPay) \(\to\) Pays USDT/LTC \(\to\) Redirects back \(\to\) Balance updates.
Action: User fills out a shipping form \(\to\) Clicks "Buy Label."
Backend: Checks Balance \(\to\) Deducts Cost \(\to\) Calls My Custom API \(\to\) Returns PDF Label.
Key Features (Must be flawless):
1. The "Create Label" Form:
Constraint: US-to-US addresses only.
Address Book: Auto-save new addresses. Dropdown to auto-fill previously used addresses.
Randomizer Button: A small button next to email/phone fields that, when clicked, auto-fills a random realistic email/phone number.
Duplicate: A "Clone" button on past orders that pre-fills the form with that data for a new shipment.
2. The Dashboard:
Simple table of history (Date, Recipient, Cost, Tracking #).
"Download Label" button.
3. Settings:
Simple page to update Password and Email.
Technical Requirements:
NO PHP. Preferred Stack: MERN (Mongo/Express/React/Node)
Mobile Responsive: The "Create Label" form must work perfectly on mobile devices (no zooming issues, broken inputs, or scrolling bugs).
Concurrency Handling: You must ensure that if a user has $10, they cannot fire two API calls simultaneously to spend that same $10 twice.
What I Provide:
The API: A custom REST API endpoint for label generation.
The Design/Flow: Access to a live example site to mimic.
The Gateway: API keys for the Crypto Payment Gateway.