Backend Engineer
- Built the Go backend behind PLN electricity payments: prepaid tokens, postpaid bills, and electric-stove purchases. Delivered the end-to-end order and payment flow: WhatsApp OTP login with slide-captcha protection, PLN Data Gateway inquiry, and Virtual Account issuance through bank and PSP integrators (BTN, Winpay), plus SSO officer access and secured internal APIs for revenue and reconciliation reporting.
- Contributed to the mini app PPOB services: the transaction and billing API, a cron-driven scheduler that expires payments, retries pending billings, and syncs provider status, and the internal back-office for products, settlement, and reconciliation.
- Built the gamification campaign engine across the mini app services: rule-based eligibility from successful transactions, server-side weighted reward draws, an inventory-safe reward ledger with idempotent claims, an admin console for campaign setup, and scheduled jobs that activate campaigns and expire entitlements automatically.
- Building a Bank Indonesia SNAP-standard payment gateway on a Go microservices architecture (gRPC, PostgreSQL, Redis, Kafka) covering Virtual Account, e-wallet (DANA, MotionPay, GoPay), and QRIS channels, with per-bank PSP integrators and automated reconciliation and settlement, in development for production rollout.
- Engineered a real-time fraud monitoring service for the payment gateway that flags suspicious activity (velocity, volume, ratio, and operational-hours rules) into reviewable incidents for fraud analysts. The gateway only collects payments, so the service surfaces alerts rather than blocking transactions.