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Ahad Brothers billing & inventory
Billing and stock control for Ahad Brothers, an educational shop: customer bills, inventory and payments in one SolidJS and NestJS application.
Built byAhsan NadeemAbout this project
The challenge
Ahad Brothers, an educational shop, needed one system to bill customers at the counter and keep track of every item on its shelves, so that sales and stock always tell the same story.
The approach
ZNova built a web application with a SolidJS front end and a NestJS API, on PostgreSQL through Prisma. Staff sign in, create a customer's bill and manage inventory from the same screens, while payment steps and stock changes are written as database transactions, so a sale and its stock movement are recorded together or not at all.
The outcome
The shop bills its customers and manages its inventory in one application, with a consistent record behind every sale. ZNova is now building Ahad Brothers' online store on the same foundations.
Inside the product.
A look at the screens. Drag the front one aside or use the arrows to flip through.
- billing-inventory-app / billing
Billing (1 / 3)
How it's built, layer by layer.
From what people see down to what it runs on, with the stack behind each layer.
billing-inventory-app · architecture
Interface
- SolidJS
- Sign-in for shop staff
- Billing screen for customer bills
- Inventory screens
API
- NestJS
- TypeScript
- Billing and inventory modules
- Payment-related workflows
- Authentication for every request
- PDF export
Data
- Prisma
- PostgreSQL
- Typed queries through Prisma
- Bills and stock movements as transactions
What shipped.
The capabilities that went live, one card each.
Customer bills
Staff create a customer's bill in a few steps at the counter.
Inventory management
Stock is managed in the same application that bills for it, so counts follow every sale.
Payment workflows
Payment-related steps sit next to the bills they settle.
Secure sign-in
Only signed-in staff can create bills or change stock.
One consistent record
Bills and stock changes are saved as database transactions, together or not at all.
Typed end to end
TypeScript from the SolidJS screens through the NestJS API to Prisma's queries.
Decisions that shaped it.
The engineering calls behind the build, and why they were made.
Transactions as the source of truth
Billing and stock changes go through database transactions, so a sale and its stock movement are recorded together or not at all.
One system, not three
Billing, inventory and payments share one application and one database instead of separate tools that drift apart.
Types from screen to database
Prisma generates typed queries from the schema, and TypeScript carries those types through the API to the screens, so a schema change shows up as a compile error, not a wrong bill.
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