Full Stack Java Developer

Full-stack microservices architecture with Spring Boot, GraphQL, and event-driven communication. This section demonstrates a task management platform built with four Java services, PostgreSQL, MongoDB, Redis, and RabbitMQ — deployed on Kubernetes.

Every Java service exposes Prometheus metrics to a live Grafana dashboard.

Task Management System

A full-stack project management application demonstrating Spring Boot microservices, PostgreSQL, MongoDB, Redis, RabbitMQ, GraphQL, Google OAuth, and Kubernetes — all orchestrated with Docker Compose and CI/CD via GitHub Actions.

Tech Stack

• 4 Spring Boot microservices (gateway, task, activity, notification)
• GraphQL API gateway with JWT authentication
• PostgreSQL (tasks), MongoDB (activity logs), Redis (notifications)
• RabbitMQ event-driven architecture
• Google OAuth 2.0 login
• Next.js + TypeScript + Apollo Client frontend
• Minikube Kubernetes deployment (production), Docker Compose (local dev)
• CI/CD with GitHub Actions, Testcontainers, security scanning

Analytics & Database Optimization

The task-service exposes an analytics query layer backed by Flyway migrations, compound and partial indexes, Redis caching, HikariCP tuning, and MongoDB aggregation pipelines in the activity-service. The GraphQL gateway composes these into a single projectHealth query (see ADR docs/adr/java-task-management/07_analytics_and_optimization.md).

Architecture

Four Spring Boot services fronted by a GraphQL gateway. Writes land in Postgres; events fan out through RabbitMQ to the activity and notification services, which persist into MongoDB.

Request flow: Create a task

One click traces through the gateway, into task-service, onto RabbitMQ, and fans out to activity and notification consumers in parallel.