Wanchai Nupinit — High-Reliability Backend & Crypto Infrastructure.
For 3+ years at Bitkub — Thailand's leading crypto exchange — I've owned the Wallet domain end-to-end: FIDO2/WebAuthn passkey auth, real-time fraud detection, and compliance systems serving millions of users at 99.5%+ uptime with zero critical security incidents. I write Go, think in microservices, and ship things that stay up at 3am without anyone having to wake up.
Bitkub Online Co., Ltd
Senior Software Engineer — Crypto Wallet Team
Bangkok, Thailand
Sole backend owner of Bitkub's Crypto Wallet domain — Golang microservices powering crypto deposits and withdrawals for millions of users at 99.5%+ uptime with zero critical security incidents over 3 years. Shipped passkey auth, real-time fraud detection, and compliance systems end-to-end.
PTT Digital Solutions Co., Ltd
Full Stack Developer
Bangkok, Thailand
Built real-time event notification microservice and operational monitoring dashboard for PTT fuel station network — alerting operators on anomalies and enabling regional managers to track multi-site KPIs in a single view.
Technical Ecosystem
Deep expertise in distributed systems, security, and cloud-native architecture.
Languages
Go (Golang)
TypeScript
JavaScript
Python
SQL
Backend & APIs
Node.js
REST API
Microservices
RabbitMQ
Kafka
Frontend
ReactJS
Next.js
HTML/CSS
Databases
MySQL
MongoDB
Redis
Elasticsearch
High-Impact Projects
All Projectsarrow_forward
Passkey Crypto Withdrawal
Designed and implemented FIDO2/WebAuthn biometric authentication for crypto withdrawal, eliminating SMS OTP vulnerabilities and SIM-swap attacks.
- Designed credential registration flow, server-side verification, and device binding.
- Eliminated SMS OTP vulnerability — zero SIM-swap incidents post-launch.
- Coordinated with security team for threat modeling and pentest review.
Mule Account Detection
Automated fraud detection system to identify mule accounts used for money laundering using async scoring pipeline.
- Scoring pipeline using multiple signals: transaction patterns, account age, behavioral data.
- Async RabbitMQ architecture — zero latency impact on main withdrawal flow.
- Collaborated with compliance team to define rules and tune false-positive thresholds.
FaceCheck Verification
Integrated liveness detection into the crypto withdrawal verification flow to prevent account takeover fraud.
- Built API layer connecting Bitkub's backend to 3rd-party liveness check provider.
- Reduced account takeover fraud via biometric identity verification.
Etax System Redesign
Re-architected the Etax (electronic tax document) system from a monolithic EC2 process into a stateless Golang microservice.
- Before: monolithic process running 5–6 hrs/day on dedicated EC2 instance.
- After: reduced to 2–3 hrs/day (~50% improvement).
- Stopped idle EC2 instance → saved $300.08/month in infrastructure costs.
Get in Touch
Looking for a senior engineer to architect your next high-reliability system?
