Java demo showcasing both the Observer and Publish/Subscribe design patterns. Includes simple, practical implementations to highlight their differences.

A distributed J2EE Online Auction System utilizing EJB (Enterprise Java Beans) (Singleton, Stateless, MDB) & JMS for high-concurrency, asynchronous bid processing. Features realtime updates via WebSockets, thread-safe concurrency control, & a Bootstrap/jQuery UI powered by Jackson JSON serialization, deployed as a scalable EAR (Enterprise Archive)

Simulação de fluxo de pedidos assíncrono com Spring Boot e ActiveMQ. Demonstra mensageria (JMS), desacoplamento e processamento entre microserviços independentes.

Agibank challenge | Scalable financial contract validation service with high-volume asynchronous processing

Event-driven Spring Boot system using Apache Kafka for decoupled order processing and inventory management, with modular architecture and Docker-based orchestration.

A service for interacting with the Kindle catalog of books. Users can retrieve books and recommendations, remove old books, and submit new versions of books for publishing to the catalog. In order to accomplish this, I implemented asynchronous processing and thread safety.

A robust, scalable payment gateway system built in Java, designed to demonstrate Low-Level Design (LLD), clean architecture, and real-world backend engineering concepts such as idempotency, asynchronous processing, and webhook reliability.

HTTP API with asynchronous data processing using RabbitMQ and Spring Boot

Notification Management Microservice for StayEase built with Spring Boot, Java 21, MySQL, Spring Security, Spring Data JPA, JavaMailSender, Asynchronous Processing, and Gradle. Supports reliable email notifications, duplicate notification prevention, automatic retry with exponential backoff, notification status tracking, and seamless microservices

Built a distributed task processing system using Spring Boot and RabbitMQ, implementing asynchronous processing with retry mechanism, Dead Letter Queue (DLQ), delayed retries, and idempotent worker design for fault tolerance and scalability.

물류 센터 바코드 수집 파이프라인, 설계부터 부하·장애 검증까지. Kafka → Redis Streams → 배치 적재로 이어지는 비동기 구조를 Docker 다중 컨테이너로 구성하고, 응답 시간과 DB 쓰기 부하 개선, 장애 격리, 무손실을 실측으로 검증했습니다.

JavaFX desktop application for local log analysis, filtering, timelines and CSV export

REST API sviluppata con Java 21 e Spring Boot per gestire città tramite CAP, raccogliere dati meteorologici da Open-Meteo e consultare medie precalcolate. Include raccolta asincrona, prevenzione dei duplicati, Swagger UI e Docker.

This Spring Boot application demonstrates several key architectural patterns for handling large document processing without blocking operations or memory issues:

Distributed async notifications: Spring Boot API and batch workers, RabbitMQ retries/DLQ, PostgreSQL, mock email/SMS, NGINX—event-driven reliability and load-testing reference.

🚀 Build and manage a high-availability online auction system with real-time bidding using Java EE, EJB, JMS, and a responsive user interface.