Backend Developer (Java / Spring Boot)
Systems-Oriented Engineer building production-ready APIs.

I began programming during the pandemic by creating calculation tools to automate engineering computations. What started as small utilities evolved into a deep interest in backend systems and architecture.

For nearly three years, I’ve consistently studied and built with Java and Spring Boot while working full-time as a mechanical engineer.

Today, I focus on building structured, domain-driven backend systems with clean architecture and strong business rule enforcement.

My engineering background strengthens my:

• Analytical and critical thinking
• Systems-level reasoning
• Structured problem solving
• Attention to detail
• Discipline and long-term consistency

• Java 21
• Spring Boot 3
• JPA / Hibernate
• PostgreSQL
• REST API Design
• Swagger / OpenAPI

• Layered Architecture
• Modular Monolith Design
• Domain Modeling
• Business Logic inside Service Layer
• DTO separation (Request / Response)
• Validation & Data Integrity rules

• JUnit
• Mockito
• Service-layer unit testing

• Dockerized application
• VPS-hosted production API
• Environment-based configuration

Repository:
Inventory + POS Backend

Live API (Swagger):
https://inventory-api.renzoproject.site/swagger-ui/index.html

A modular monolith backend designed for real-world business scenarios.

Core domains include:

• Product catalog with variants and pricing history
• Inventory management with stock movements
• Sales lifecycle (OPEN → COMPLETED → CANCELLED)
• Payments and applied discounts
• Refund processing with strict validation rules
• Receipt generation for completed sales

This project emphasizes:

• Strong domain modeling
• Clear separation of concerns
• Transactional integrity
• Enforced business constraints
• Production deployment

• Transitioning into a Backend Developer role
• Deepening expertise in backend architecture
• Expanding toward full-stack capability (React / Angular)
• Studying microservices architecture fundamentals

Open to Backend Developer opportunities where I can contribute to real-world systems and continue growing as an engineer.