Muthukumar K.
Senior Java Backend Developer
Experience
Senior Java Backend Developer
Upwork
- Developed Java 21 / Spring Boot 3.2 microservices with REST and GraphQL APIs for GDPR-compliant consent workflows using Hexagonal Architecture.
- Enhanced Backend-for-Frontend (BFF) performance, applying AI-assisted tools for code refactoring and optimization across global customer platforms.
- Built event-driven workflows with Kafka, RabbitMQ, AWS SQS, and integrated Salesforce Marketing Cloud for real-time consent tracking.
- Implemented OAuth2/Keycloak security, automated CI/CD with Jenkins, GitHub Actions, Gradle, and deployed containerized services on Docker/Kubernetes with AWS and Azure.
- Executed unit, integration, and contract testing with JUnit 5, TestNG, Mockito, and TestContainers, while monitoring performance via Grafana, Kibana, and CloudWatch.
Senior Java Backend Developer
Upwork
- Developed Java 21 / Spring Boot 3.2 microservices using Hexagonal Architecture for digital identity verification and e-signature management, ensuring modularity and scalability.
- Integrated Keycloak 24.x with OAuth2.1 and OpenID Connect for SSO and RBAC, enhancing secure authentication and EU eIDAS compliance.
- Designed API-first microservices with OpenAPI 3.1, Swagger, and GraphQL, improving interoperability with external providers while reducing integration complexity.
- Built event-driven workflows using Kafka, RabbitMQ, and AWS SQS, applying AI-assisted tools for code refactoring and performance optimization.
- Automated CI/CD pipelines with Jenkins, GitHub Actions, Gradle, containerized services with Docker/Kubernetes, deployed on AWS EKS and Azure, monitored via Grafana, Kibana, CloudWatch, and TestContainers.
Senior Java Developer
Accenture
- Developed Java 21 / Spring Boot 3.1 microservices for quoting, claims, and policy renewals using Hexagonal Architecture and DDD for modular, scalable systems.
- Implemented asynchronous event-driven workflows using Apache Kafka 3.6, RabbitMQ, and ActiveMQ to improve responsiveness and scalability.
- Integrated GraphQL APIs with REST endpoints and applied AI-assisted tools for code refactoring and optimization, reducing payload overhead.
- Utilized gRPC v1.56 for high-performance inter-service communication, decreasing latency by 20% versus REST-based calls.
- Managed data persistence using MongoDB 6.0, Couchbase 7.2, Redis 7.2, and PostgreSQL, optimizing caching and hybrid storage performance.
- Secured backend APIs using OAuth2.1, Keycloak 24.x, and JWT, enabling SSO, RBAC, and compliance with enterprise security standards.
- Automated CI/CD pipelines with Jenkins 2.440, GitHub Actions, and Gradle; containerized deployments with Docker 24.x/Kubernetes on AWS EKS/ECS and Azure.
- Integrated Salesforce middleware and Shopify APIs to synchronize policy and quote data, improving CRM and backend communication.
- Configured Grafana 10.x, Kibana 8.x, and AWS CloudWatch dashboards for observability, performance tuning, and anomaly detection; used TestContainers for integration testing.
- Ensured end-to-end system reliability and scalability across distributed microservices, monitoring performance and optimizing JVM throughput and concurrency.
Senior Java Developer
Engineering Group
- Developed Java 17 / Spring Boot 2.6 microservices for account and payment processing using Hexagonal Architecture, ensuring modularity and high scalability.
- Integrated REST and GraphQL APIs, applying AI-assisted tools for code refactoring and performance optimization across banking services.
- Implemented asynchronous workflows using Kafka 2.8 and ActiveMQ 5.16, enabling real-time transaction updates and notification delivery.
- Managed Oracle 19c and PostgreSQL 13 databases via Spring Data JPA and Flyway, optimizing queries and ensuring schema evolution.
- Automated CI/CD pipelines using Jenkins and GitHub Actions, containerized microservices with Docker 20.10, deployed on AWS EKS/Kubernetes.
- Secured APIs with Keycloak/OAuth2.1 and JWT, implementing federated SSO and role-based access control for sensitive financial data.
- Configured Grafana, Kibana, Prometheus, and AWS CloudWatch for monitoring, performance tuning, and proactive anomaly detection; used TestContainers for integration testing.
- Applied JVM optimization techniques and multithreading strategies to enhance backend performance and transaction throughput.
- Integrated Salesforce APIs for customer data synchronization, ensuring seamless CRM interaction and consistent data across banking workflows.
- Ensured observability, resilience, and scalability of distributed systems through container orchestration, cloud deployment, and AI-assisted code review tools.
Senior Java Developer
Iason
- Developed Java 12 / Spring Boot 2.2 microservices for employee and inventory management, integrating REST APIs and applying AI-assisted tools for code optimization.
- Implemented asynchronous workflows using Apache Camel 3.x, Kafka 3.6, RabbitMQ 3.9, and ActiveMQ 5.x for reliable backend messaging.
- Secured services with Spring Security, OAuth2.0, Keycloak, and JWT, ensuring role-based access control and compliance across internal systems.
- Automated CI/CD pipelines with Jenkins 2.440, GitHub Actions, and Gradle; containerized deployments with Docker 20.10 on AWS EKS/ECS and Azure.
- Enhanced observability and performance with Grafana 8.x, Kibana 7.x, AWS CloudWatch, and TestContainers for integration testing.
Java Developer
Reply Srl
Developed modular microservices for employee and inventory management using Java 12, Spring Boot 2.2, enabling scalable backend operations and preparing for future IoT integrations.
Secured APIs and services with Spring Security, OAuth2.0, HTTPS, and role-based access control (RBAC), ensuring compliance and controlled access across internal and external systems.
Implemented asynchronous, event-driven processing using Apache Camel 3.x, Kafka 3.6, RabbitMQ 3.9, and ActiveMQ 5.x, supporting reliable IoT telemetry and backend messaging workflows.
Containerized microservices with Docker 20.10 and deployed on AWS EKS/ECS, leveraging AWS Secrets Manager for secure credential management and scalable cloud infrastructure.
Automated CI/CD pipelines with Jenkins 2.440 and Maven 3.8, integrating JUnit 5 and Mockito for testing, and maintained observability with AWS CloudWatch, Grafana 8.x, and Kibana 7.x for proactive monitoring and diagnostics.
Developed backend billing and accounting microservices using Java 11, Spring Boot 2.0, and Spring MVC, applying REST and GraphQL APIs for efficient data querying and integration.
Implemented OAuth2.0, Keycloak, and JWT for secure authentication, ensuring compliance with enterprise-grade access and encryption standards.
Designed multi-threaded and event-driven workflows using Apache Kafka 3.5 and ActiveMQ 5.x, enabling asynchronous communication and high system throughput.
Automated build and deployment with Jenkins 2.440, Maven 3.8, and GitHub Actions, containerizing services via Docker 20.10 and deploying to AWS EKS with Kubernetes 1.22.
Enhanced performance with Redis 7.x caching and hybrid data storage using MongoDB 6.0 and Couchbase 7.2, monitored with Grafana and Kibana for observability.
Converted a web application using the iText library for PDF document signing to ASP.NET for digital signature, involving API calls, key exchange, hashing, and PDF processing using RUPS, pdfSweep, and pdfHTML.
Refactored legacy code and implemented a password-based encryption algorithm using PBE with MD5 and DES, increasing application security.
Java Automation Tester
Inetz Tech Solutions
- Selected the test cases to be automated and performed functional testing of the front-end using Selenium IDE and WebDriver, and created the data driven framework using TestNG.
- Conducted browser testing in parallel on various machines using Selenium Grid.
- Developed the persistence layer using Hibernate ORM, utilizing the Hibernate Query Language API and the singleton pattern.
- Developed queries using HQL and the Query Criteria API of Hibernate 5.0.
Web Developer
Infiniti Software Solutions Pvt. Ltd
- Developed a travel automation platform to provide backend support to various travel agencies.
- Integrated multiple GDS/APIs and accounting systems into the online booking tool to automate processes.
- Worked with MVC framework and front-end development using HTML, CSS, Bootstrap 3.0.0, JavaScript, jQuery, MySQL, PostgreSQL, and MongoDB.
Software Application Developer
Apollo Computer Education
- Developed a MATLAB coding project for school students.
- Integrated system project utilizing microcontrollers, Raspberry Pi, and Embedded C.
Summary
Senior Java Backend Developer with 8+ years of experience in designing and developing scalable microservices using Java 8-21 and Spring Boot. Skilled in Hexagonal Architecture, DDD, REST/GraphQL APIs, and event-driven systems with Kafka, RabbitMQ, and Apache Camel. Experienced in secure authentication (OAuth2.1, OpenID Connect, Keycloak), CI/CD automation (Jenkins, GitHub Actions, Maven, Gradle), and containerized deployments on Docker, Kubernetes, AWS, and Azure. Proficient in cloud integrations, AI-assisted code optimization, and middleware (Salesforce, Shopify), ensuring high performance, reliability, and observability across distributed systems.
Languages
Education
VIT University
Doctorate from Research (PhD) in Communications Digital · Communications Digital · Vellore, India
Anna University
Masterful - Technology of Information, IoT, Big Data Analytics and Cloud Computing · Technology of Information · Chennai, India
Anna University
Three-Year - Technology of Information, Programming Python, Cloud Computing, IoT and Programming in C · Technology of Information · Chennai, India
Certifications & licenses
Driving Licence: B
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