At GreenPay, I designed NATS-based payment processing with idempotent handlers, retries, and a dead-letter queue, improving successful payment conversion from 68% to 80%. I also developed payment-core services and consistent balance updates for 500+ merchants.
Previously, I designed a Kafka pipeline processing about 5M events per day for a container-security project and built transaction-processing services at FinTech Broker. At Wildberries, I developed cart and user-account backend services and introduced Redis session caching that reduced verification time from about 40 ms to 5 ms.
