# Mateus R. Campos — Backend Developer

> Backend Developer focused on Java/Spring Boot, Node.js, and REST APIs, with a strong background in research, data, and technical documentation.

- **Canonical:** https://portfolio-mateusribeirocampos.vercel.app
- **Language:** English (en)
- **Machine-readable source:** https://portfolio-mateusribeirocampos.vercel.app/portfolio.md?lang=en

## Profile

I’m Mateus R. Campos, a Computer Science graduate and Backend Developer. My background also includes international scientific research, data analysis, and structured problem-solving. I apply this experience to developing REST APIs, authentication and authorization solutions, service integrations, automated tests, and reliable, maintainable applications.

## How I work

### Integration-oriented backend

I design REST APIs, authentication, authorization, and service integrations with attention to contracts, data, and operational continuity.

### Verifiable quality

I use automated tests, TDD when it fits, documentation, and version control to reduce regressions and make maintenance easier.

### Analytical thinking

From scientific research, I bring the ability to break down problems, validate hypotheses, and communicate technical decisions clearly.

## Core capabilities

- **Backend:** Java 21, Spring Boot, Spring Security, JPA/Hibernate, Node.js, Express.js
- **Testing:** JUnit 5, Mockito, TDD, Jacoco, MockMvc, RestAssured
- **Frontend:** React, Next.js, TypeScript, JavaScript, React Native
- **Databases:** PostgreSQL, MySQL, MongoDB, SQLite
- **DevOps:** Docker, GitHub Actions, Git, CI/CD
- **Deploy:** Vercel, Render, Supabase, Swagger/OpenAPI

## Experience

### Backend Development Intern

- **Organization:** Isaac Kennedy Desenvolvimento de Software LTDA
- **Period:** 08/2025 - 11/2025

Worked on backend application development and maintenance, focused on APIs, data, stability, and collaboration in an agile environment.

- Developed and maintained backend applications using Node.js.
- Implemented RESTful APIs and integrated SQL and NoSQL databases.
- Handled bug fixing, automated tests, Git version control, and Scrum/Kanban project tracking.

### Researcher I

- **Organization:** Institut Sophia Agrobiotech, INRAE - CEA Team
- **Period:** 01/2017 - 01/2019

Applied research in complex projects with international teams, data analysis, and scientific communication in English.

- Led multidisciplinary projects with advanced statistical analysis in R and Python.
- Developed predictive models for complex biological systems.
- Published scientific results and produced technical documentation for international audiences.

## Featured projects

### CVnoAlvo

Web application for adapting resumes to specific job openings, with compatibility analysis, ATS-focused artifact generation, Java/Spring backend, PostgreSQL, and JWT authentication.

- **Type:** Production product
- **Status:** Live
- **Architecture:** Next.js -> Java 21 API -> Spring Security -> PostgreSQL -> External services
- **Technologies:** Java 21, Spring Boot, Spring Security, JWT, PostgreSQL, Docker, Next.js

**Engineering evidence**

- **Product:** A guided workflow that turns a job opening into ATS-focused resume artifacts.
- **Backend:** Java/Spring services with JWT security and PostgreSQL persistence.
- **Delivery:** Full-stack product running in production with external integrations.
- [Live product](https://www.cvnoalvo.com.br)

### DSCommerce

E-commerce REST API with products, categories, users, orders, OAuth2/JWT authentication, role-based authorization, JPA/Hibernate persistence, and OpenAPI documentation.

- **Type:** Backend API
- **Status:** Public deployment
- **Architecture:** REST API -> Spring Security -> Service layer -> JPA / Hibernate -> PostgreSQL
- **Technologies:** Java 21, Spring Boot 3, Spring Security, OAuth2, JWT, PostgreSQL, JPA, Docker

**Engineering evidence**

- **Security:** OAuth2/JWT authentication with role-based authorization.
- **Domain:** Products, categories, users and orders modeled as API resources.
- **Delivery:** OpenAPI documentation, Maven build and containerized deployment.

- [Source code](https://github.com/mateusribeirocampos/project-spring-boot-dscommerce)
- [Live product](https://project-spring-boot-dscommerce.onrender.com)

### SYSMP

Full-stack deadline management system with JWT authentication, an admin dashboard, PostgreSQL, and real-time communication for operational follow-up.

- **Type:** Full-stack system
- **Status:** Private product
- **Architecture:** React -> Express API -> JWT -> WebSocket -> PostgreSQL
- **Technologies:** Node.js, Express, React, TypeScript, WebSocket, PostgreSQL, JWT

**Engineering evidence**

- **Operations:** Administrative workflows for users, documents and deadlines.
- **Real time:** WebSocket communication for operational status updates.
- **Security:** JWT authentication protecting administrative access.

- [Source code](https://github.com/mateusribeirocampos)

## Additional projects

### Dragenda

Healthcare scheduling application with a React frontend, Node.js/Express backend, SQLite persistence, and separate frontend/backend deployments on Vercel and Render.

- **Type:** Scheduling application
- **Status:** Public demo
- **Technologies:** React, React Native, Bootstrap, Node.js, Express, SQLite

- [Source code](https://github.com/mateusribeirocampos/dragenda)
- [Live product](https://dragenda.vercel.app)

### Website - Santa Rita church

Responsive institutional website for Santa Rita Church, built with React, TypeScript, Vite, and Tailwind CSS for clear content organization and mobile access.

- **Type:** Institutional website
- **Status:** Live
- **Technologies:** React.js, TypeScript, Tailwind CSS, Vite

- [Source code](https://github.com/mateusribeirocampos/santarita)
- [Live product](https://igrejasantaritaourofino.vercel.app/)

### DIO - Machine Learning

Study repository from the DIO Machine Learning Practitioner Bootcamp, with Python notebooks for facial recognition, image recommendation, and virtual assistant experiments.

- **Type:** Applied studies
- **Status:** Study repository
- **Technologies:** Jupyter Notebook, Python, Keras, R, Machine Learning, Deep Learning

- [Source code](https://github.com/mateusribeirocampos/diollm)
- [Live product](https://colab.research.google.com/github/mateusribeirocampos/diollm/blob/main/Notebooks/Project_Draft/Sistema_de_recomenda%C3%A7%C3%A3o_por_imagens_.ipynb)

## Education

- **Computer Science:** Universidade Anhembi Morumbi (2022-2026)
- **Doctor of Science in Entomology:** UFRPE (2009-2013) | Visiting Scholar: University of Nebraska-Lincoln (USA)
- **Master of Science in Entomology:** UFV (2007-2009)
- **Bachelor's in Agronomy:** UFV (2002-2007)

## Contact

- **Contact form:** https://portfolio-mateusribeirocampos.vercel.app/contact
- **GitHub:** https://github.com/mateusribeirocampos
- **LinkedIn:** https://www.linkedin.com/in/mateus-ribeiro-de-campos-6a135331/
- **Website:** https://portfolio-mateusribeirocampos.vercel.app