Backend Software Engineer focused on Java, Spring Boot, REST APIs, software architecture, testing, and technical documentation.

I use this GitHub as a professional engineering portfolio: a place to document how I design, build, test, and evolve backend systems with clarity and long-term maintainability.

• Modern Java, from Java 17 to the latest stable releases, and Spring Boot 3
• REST API design and backend architecture
• Authentication and authorization with Spring Security
• PostgreSQL, JPA/Hibernate, migrations, and data modeling
• Automated tests with JUnit, Mockito, and Testcontainers
• Docker, CI/CD, observability, and production-minded documentation
• TypeScript and React for frontend integration and full product demos
• Clean code, maintainable design, and technical decision records

I am reorganizing this profile around a smaller set of well-documented public repositories. The goal is to keep public projects that are easy to understand, clone, run, test, and evaluate.

Planned portfolio standards:

• Clear README with project purpose, architecture, stack, setup, and testing instructions
• Architecture notes and ADRs for important technical decisions
• Automated tests and CI pipelines
• Docker-based local environment when useful
• OpenAPI documentation for REST APIs
• Roadmap, changelog, and issue-based development

Portfolio-grade backend project built incrementally to demonstrate Java, Spring Boot, REST APIs, Flyway migrations, validation, automated tests, CI, and documentation through a real SaaS billing domain.

Current implemented slices:

• Organizations
• Customers
• Plans
• Subscriptions
• Subscription cancellation

Repository: https://github.com/joaoscioli/subscription-billing-api

A structured knowledge base about the Spring ecosystem, covering Spring Boot, Spring Framework, Spring Data, Spring Security, Spring Cloud, messaging, integration, documentation, and related projects.

Repository: https://github.com/joaoscioli/everything-about-spring

Experiments and practical labs combining Spring Boot and AI-oriented backend services. This repository is being improved into a stronger portfolio project with tests, CI, documentation, and clearer architecture.

Repository: https://github.com/joaoscioli/spring-ai-in-action-labs

A growing repository for software architecture, design principles, architectural patterns, and engineering trade-offs.

Repository: https://github.com/joaoscioli/everything-about-software-architecture

The main implementation project in progress is the Subscription Billing API. The current goal is to evolve it from a strong backend foundation into a complete portfolio case study with authentication, role-based access control, observability, ADRs, API documentation, and deployment notes.

I value systems that are understandable before they are clever. My engineering style prioritizes explicit trade-offs, small iterations, automated verification, and documentation that helps the next developer move faster.

• GitHub: https://github.com/joaoscioli
• LinkedIn: https://www.linkedin.com/in/joaoscioli
• Email: joaoscioli@outlook.com