Istanbul, Türkiye
Principal Software Engineer with 15+ years of experience designing, building, and operating large-scale enterprise Java systems in banking, payments, and digital platforms. Expert in object-oriented design, distributed systems, microservices, concurrency, and event-driven architectures. Proven leader in delivering highly scalable backend platforms, mentoring engineers, and driving architectural decisions in complex enterprise environments.
- Led technical analysis, architectural design and development for an enterprise-scale e-mail platform serving 1.5M+ individual users and 44K+ enterprise customers, and a personal cloud storage platform serving 5M+ users and managing 5.8B+ files, focusing on scalable backend services and system reliability. - Developed RESTful APIs, backend services, and batch jobs using Java, Spring Boot, RabbitMQ, Kafka, Redis, Cassandra, Oracle, MySQL, OpenStack and Ceph. - Ensured system quality through unit/integration testing, load testing (JMeter), logging, and monitoring. - Implemented ELK Stack, Grafana, and Prometheus for observability and incident diagnosis. - Contributed to frontend web applications using Angular, React, TypeScript, and SCSS. - Built and maintained CI/CD pipelines with Docker and Jenkins. - Mentored junior engineers and supported Agile development practices.
- Served as developer lead on mission-critical payment systems supporting 450,000+ POS terminals and 350,000+ merchants. - Designed and implemented concurrent batch processing systems with strict time and reliability constraints. - Developed Spring-based services, SOAP APIs, and Oracle PL/SQL components. - Worked extensively on transaction management, concurrency, and system reliability.
- Developed and enhanced internet banking applications using Java, Spring MVC, and JSP. - Delivered enterprise web solutions using JavaScript, AJAX, jQuery, and CMS platforms.