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I'm a Senior Software Engineer with 7 years of experience, focusing on backend development, scalable architectures, and event-driven microservices using Java, Spring Boot, Redis, and AWS. I have a fintech background building secure, high-volume payment systems handling over a million transactions per day, and I excel at reliability, performance optimization, and modernizing distributed infrastructure.…I'm a Senior Software Engineer with 7 years of experience, focusing on backend development, scalable architectures, and event-driven microservices using Java, Spring Boot, Redis, and AWS. I have a fintech background building secure, high-volume payment systems handling over a million transactions per day, and I excel at reliability, performance optimization, and modernizing distributed infrastructure.

Ujjal Kundu

Full Stack Developer, Back-End Developer, Web Developer, +2

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I'm a Senior Software Engineer with 7 years of experience, focusing on backend development, scalable architectures, and event-driven microservices using Java, Spring Boot, Redis, and AWS. I have a fintech background building secure, high-volume payment systems handling over a million transactions per day, and I excel at reliability, performance optimization, and modernizing distributed infrastructure.…I'm a Senior Software Engineer with 7 years of experience, focusing on backend development, scalable architectures, and event-driven microservices using Java, Spring Boot, Redis, and AWS. I have a fintech background building secure, high-volume payment systems handling over a million transactions per day, and I excel at reliability, performance optimization, and modernizing distributed infrastructure.

Available to hire

I’m a Senior Software Engineer with 7 years of experience, focusing on backend development, scalable architectures, and event-driven microservices using Java, Spring Boot, Redis, and AWS.

I have a fintech background building secure, high-volume payment systems handling over a million transactions per day, and I excel at reliability, performance optimization, and modernizing distributed infrastructure.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Language

English

Advanced

Work Experience

Senior Software Engineer L-I at VivaSoft Ltd. (Bkash)

January 1, 2024 - January 1, 2026

Designed and implemented a configurable chunking and scheduling framework with dynamic chunk sizing, rate limiting, distributed locking, and controlled thread execution to ensure reliable multi-pod scheduling. Led the upgrade of core services from Java 11 to Java 21 and Spring Boot 2.x to 3.x, significantly improving code quality, maintainability, and long-term platform stability. Refactored the notification component into a dedicated event-driven microservice using AWS messaging services. Improved large-scale data processing by optimizing query execution, removing unnecessary calls, applying indexing strategies, and introducing scheduled data archiving. Mentored junior engineers, participated in technical hiring, and led multiple production deployments to ensure delivery quality and operational stability. Collaborated with DevOps, Product Owners, and Stakeholders during sprint planning to deliver features for a subscription-based payment platform. Implemented gateway API rate limiting

Senior Software Engineer L-II at VivaSoft Ltd. (Bkash)

June 1, 2022 - December 1, 2023

Built revenue-monitoring system using MV C architecture, enhancing system structure and efficiency by 20%. Designed database schemas and integrated them with applications using Spring JPA and Hibernate, improving DB performance by 25%. Migrated databases from MySQL to Oracle to meet application requirements, improving compatibility and performance by 30%. Implemented custom validation using AOP, reducing code complexity by 40% and increasing maintainability. Technologies included Java 8, Spring MVC, Gradle, Oracle PL/SQL, Jasper Reports, SVN, and a Waterfall methodology.