Case study · Food ordering · Payments
Domino's Pakistan
Digital wallet, rule-based free delivery and a refactored client API for Domino's Pakistan.
- Role
- Software Engineer at Simplex, building the features below on the backend.
- Company
- Simplex Technology Solutions
- Stack
- NestJS · Node.js · React · MySQL · GTM
01Project
What the system is
Domino's Pakistan takes customer orders online. At Simplex Technology Solutions my work on the platform focused on checkout flexibility and the quality of the APIs its clients depend on.
02Problem
What needed solving
Checkout needed more flexibility: wallet credits as a way to pay, and free delivery decided by time, channel, deals and location instead of a fixed threshold. The client-facing APIs these features depend on also needed restructuring.
03Contribution
What I worked on
- Built the wallet and free-delivery checkout features on the backend.
- Refactored the existing client-facing APIs.
04Engineering
What shipped
- 01
Digital wallet
Customers can hold wallet credits and use them to pay, which makes checkout more flexible.
- 02
Dynamic free delivery
Free-delivery eligibility is decided by rules on time, channel, active deals and the customer's location instead of a fixed threshold.
- 03
Client API refactor
Restructured the client-side APIs with stricter validation, documentation, security fixes and better performance.
05Stack
How the pieces fit
Client
- React
- GTM
Services
- Node.js
- NestJS
Data
- MySQL
06Complexity
What made it non-trivial
- Free-delivery eligibility combines four inputs, so the rules have to stay predictable when time, channel, deals and location overlap.
- Wallet credits are a balance customers spend at checkout, where any mistake is visible to them.
- Refactoring client-facing APIs means tightening structure and validation without breaking the apps that already call them.
07Outcome
What it changed
- Customers can pay with wallet credits, making checkout more flexible.
- Free delivery is decided by rules instead of a single threshold.
- Client APIs with a clearer structure, stricter validation, documentation, and security and performance fixes.