Hải Thạch

Backend Developer with a year of experience building multi-tenant SaaS applications. Designed and implemented LMS, Payment, Subscription, and Affiliate Tracking modules, with hands-on experience in payment integration, subscription lifecycle management, quota management, and event-driven workflows using Kafka. Experienced in translating business requirements into scalable backend solutions while maintaining system reliability and operational efficiency.

Pay It Today, Backend Developer at HANEXT Technology (2026-05 – Present)

Embedded payment platform integrated with Sell It Today, enabling workspace owners to distribute revenue shares to tenant members through compliant payout workflows.

• Developed and maintained RESTful APIs using NestJS and TypeScript, migrating core business logic from a legacy Supabase backend.
• Leveraged Supabase strictly for managed database services, authentication, and cloud storage.
• Implemented KYC and KYB onboarding workflows for individual users and business entities.
• Integrated with Treezor APIs to manage identity verification, compliance status, and payout eligibility.
• Built webhook processing and synchronization mechanisms to handle verification events and maintain consistency across systems.
• Monitored system reliability using Grafana, analyzing logs to efficiently troubleshoot and resolve staging environment issues reported by QA.

Sell It Today, Backend Developer at HANEXT Technology (2025-06 – 2026-05)

Multi-tenant SaaS platform that enables creators and businesses to sell digital products and online courses through one-time purchases and subscription plans. The platform includes LMS, payment processing, affiliate tracking, workspace management, and KYC-enabled payout workflows.

• Developed and maintained RESTful APIs using NestJS, TypeScript, PostgreSQL, and TypeORM.
• Designed and implemented payment workflows for one-time purchases, subscription plans, and add-on packages using Stripe.
• Built subscription lifecycle management covering upgrades, downgrades, renewals, quota allocation, payment failure recovery, and payout eligibility workflows based on Stripe KYC verification status.
• Designed affiliate tracking workflows with IP detection, fraud prevention mechanisms, and Kafka-based event publishing for downstream services.
• Implemented LMS features including course enrollment, learner progress tracking, course completion, and analytics for content creators.
• Utilized AI tools to accelerate coding and leveraged Grafana log analysis to quickly validate system issues reported by QA.

Bachelor of Information Technology in Information Technology – University of Information Technology - UIT (2026-04)

Associate Degree Sofware Development in Software Development – FPT Polytechnic College - FPL (2023-07 – 2025-09)