NDA

At Crypto Payment System, I built and scaled a high-load fintech payment platform processing around 1,500 RPS. I developed the payment system from scratch and helped evolve it from a monolith into a microservice architecture. My work covered payment processing, external provider integrations, platform reliability, developer workflows, observability, and AI-powered data processing. I designed and implemented 15 API integrations with external payment providers, built a dispute engine that reduced refund-related losses and increased net revenue by 20%, and helped grow the platform’s daily transaction volume to $100K. To support high traffic reliably, I improved database connection management with PgBouncer and built asynchronous workflows with Celery, Redis, and Kafka. I also set up CI/CD pipelines for staging and production, increased test coverage to roughly 70%, and established centralized logging and monitoring with Grafana, Loki, and Promtail. Beyond the core payment platform, I built a Telegram bot that automated support workflows and reduced operational costs by 30%, implemented two-factor authentication, developed localization publishing and SendGrid-based email services, and created AI data-processing pipelines using Kafka and Qdrant vector search. I regularly conducted code reviews and introduced AI agents into the development workflow. I care about building payment infrastructure that remains secure, observable, maintainable, and reliable under real production load.