Syed Ibna Zubayear

Lead Software Engineer

RedDot Digital Limited•  November 2020 - Present•  Dhaka, Bangladesh

• Enabled $4M+ in monthly loan recoveries by engineering a high-throughput, fault-tolerant Diameter Credit Control system in Go, processing 18K+ recharge events/sec during peak hours (~25M/day), through a non-blocking, event-driven architecture with Redis, PostgreSQL, and Kafka, achieving >99.99% uptime and replacing a legacy system with a 30x performance gain. • Achieved a 45% revenue increase by architecting scalable, low-latency microservices with Java, Spring WebFlux, Kafka, Redis, and PostgreSQL, using reactive streams, and distributed Redis caching, enabling 20K+ requests/sec and 85ms p95 latency, while maintaining 99.9% availability. • Achieved 99.999% message delivery success by developing a fault-tolerant SMPP messaging system with Kotlin, Kafka, and PostgreSQL. Utilized asynchronous processing, Kafka for message queuing, and horizontal scaling to process 30K+ messages/sec, improving delivery reliability, and minimizing downtime in telecom operations. • Led the end-to-end product development lifecycle for key services within an Agile (Scrum) environment, conducting high-quality code reviews, and collaborating with DevOps to establish CI/CD pipelines, enabling 99.9999% uptime. Drove continuous improvement through load testing and performance tuning, reducing churn by 15% and boosting user engagement by 20% within six months. • Designed and deployed scalable APIs and background workers using Spring Boot, JUnit, and Oracle DB, processing 30M+ service requests and delivering $50K in CAPEX and $200K in OPEX savings through thoughtful technical tradeoff decisions and system optimization.