Case study
Prestasia
Online tryout & exam prep platform for CPNS and Kedinasan
Prestasia is a subscription platform for Indonesian civil-service exam preparation. I built the customer product end to end: pricing and checkout, the CAT-simulated tryout engine, per-question results review and an affiliate programme with payouts.
- Role
- Product engineer — built end to end
- Context
- Own product
- Stack
- Next.js, React 19, SWR, Tailwind CSS
Overview
Most candidates prepare on a phone, on mobile data that cuts in and out. The exam had to behave like the real computer-based test without ever losing progress.
So the attempt engine journals answers on the device before they reach the network and reconciles with the server afterwards, while the deadline and grading stay authoritative on the server. A refresh, a suspended tab or a dropped connection is still a valid attempt rather than a lost one.
Key achievements
- Offline-resilient attempt engine: answers journalled locally and reconciled on reconnect
- Server-authoritative timer and grading that survive network drops
- Plan subscription, checkout, payment history and withdrawals
- Affiliate and referral programme with commission payouts