Gold & Silver Loan Management System

Overview

A staff-facing web app for a pawn-loan (gold/silver) shop, plus a self-service portal for the shop's B2B wholesale customers (Vyaparis) — covering the full loan lifecycle: pledge, release, renewal, top-up, and partial repayment, with two fully isolated authentication systems for staff vs. self-service customers.

What it does

• Architected a multi-transaction-type loan engine (pledge, release, renewal, top-up, partial-repayment) with a 3-mode interest calculator (slab/prorata/manual), validated against 799 real historical releases with zero discrepancies via a dedicated replay script.
• Built two fully isolated auth systems: NextAuth v5 (JWT) for staff with OWNER/ASSISTANT roles, and a separate custom HMAC-SHA256 signed-cookie session for the Vyapari self-service portal — no shared session concept between the two.
• Implemented dual QR/HID scanning input (Bluetooth scanner and phone-camera decode) feeding one shared per-workflow scan handler, used across single-item release, bulk release, and daily Vyapari settlement (Hishob).
• Backed by 153 unit tests (Vitest, 12 files) chaining real production interest/settlement functions, plus Playwright E2E coverage.