John Anderson Mascarelo Duarte — Senior Software Engineer

I’m a Senior Software Engineer and Full-Stack Developer with over 26 years of experience designing, developing, and leading enterprise software solutions. I specialize in Java (Spring Boot, Java EE, JPA, Hibernate) and have over 6 years of experience in React, ReactNative, Node.js, SQL, and AWS cloud. I build robust, scalable, and high-performance systems for financial, government, and corporate sectors in Brazil and Portugal. My core expertise lies in Java and its ecosystem — including Spring Boot, Java EE, JPA, Hibernate, EJB, CDI, JSF, PrimeFaces, and REST APIs — combined with over 6 years of experience in React, Node.js, SQL (Oracle PL/SQL, MySQL), and cloud platforms such as AWS. I’ve also worked extensively with application servers such as JBoss, WildFly, and Tomcat. Throughout my career, I’ve led technical teams, defined architecture strategies, and integrated mission-critical platforms with a focus on security, availability, and performance. I’m equally comfortable designing systems from scratch or modernizing legacy applications to meet modern standards. Passionate about clean architecture, code quality, and continuous learning, I strive to leverage my deep technical background and leadership experience to build solutions that are both technically excellent and strategically impactful. Main Technologies: Java | Spring Boot | JSF | Primefaces | React | React Native | Node.js | AWS | Kubernetes | Docker | CI/CD Pipelines | Microservices

Stackforce AI infers this person is a Full-Stack Developer with expertise in Fintech and Healthcare solutions.

Location: São Paulo, Brazil

Experience: 27 yrs 4 mos

Skills

Java
Spring
React
Aws
Jsf
Financial Systems

Career Highlights

26 years of experience in enterprise software solutions.
Led development of AI-driven platforms recognized globally.
Expert in Java ecosystem and cloud technologies.

Work Experience

Capgemini

Senior Java Developer (Instituto de Informática, I.P. – Portugal) (3 yrs 3 mos)

JD Digital Tecnologia

Senior Full-Stack Developer | Technical Lead (5 yrs)

Trace Sistemas

Software Development Coordinator (Java/PLSQL) (11 yrs 6 mos)

TotalBanco (now part of TOTVS Financial Systems Division)

Software Factory Coordinator / Senior Java Developer (8 yrs 8 mos)

Education

Postgraduate Specialization in Forensic Computing and Digital Investigation at IPOG - Instituto de Pós-Graduação e Graduação

Postgraduate Specialization in Software Engineering at Universidade Gama Filho

Bachelor’s Degree in Computer Systems at ULBRA

John Anderson Mascarelo Duarte

Senior Software Engineer

São Paulo, Brazil27 yrs 4 mos experience

Highly StableAI Enabled

Key Highlights

26 years of experience in enterprise software solutions.
Led development of AI-driven platforms recognized globally.
Expert in Java ecosystem and cloud technologies.

Stackforce AI infers this person is a Full-Stack Developer with expertise in Fintech and Healthcare solutions.

Contact

Skills

Core Skills

JavaSpringReactAwsJsfFinancial Systems

Other Skills

SQLOracleDockerGitGitLabHTMLCSSREST APIScrumJava EEJPAHibernateNode.jsReact NativeMySQL

About

Experience

27 yrs 4 mos

Total Experience

8 yrs 4 mos

Average Tenure

3 yrs 3 mos

Current Experience

Capgemini

Senior Java Developer (Instituto de Informática, I.P. – Portugal)

Feb 2023 – Present · 3 yrs 3 mos · Remote

I work at Capgemini as part of the technical team at the Instituto de Informática, I.P., responsible for corporate systems of Portugal’s Social Security. My role focuses on the development and modernization of enterprise solutions, ensuring high performance, reliability, and compliance with European technical standards.
I design and maintain systems using Java EE, Spring Boot, Hibernate, JSF, Oracle PL/SQL, and Java Swing, supporting applications that handle millions of daily transactions. I contribute to architecture design, backend optimization, and the integration of legacy systems into microservice-based environments, driving scalability and efficiency.
I also participated in projects using React for responsive interfaces and AWS for secure API integrations, improving connectivity and system interoperability.
Key Responsibilities:
Backend development with focus on scalability and performance.
Creation and maintenance of REST APIs integrated with business-critical services.
Architecture design and modernization of legacy components.
Integrations with external platforms using AWS best practices.
Automation, version control, and system stability in Linux environments.
Collaboration with multidisciplinary European teams under Agile/Scrum methodology.
Key Results and Achievements:
Resolved critical issues in a legacy accounting and payment system, improving accuracy and reliability.
Corrected benefit calculations after in-depth system and legislation analysis, ensuring data integrity.
Achieved a reduction of more than 40% in client-submitted tickets, enhancing stability and user satisfaction.
These initiatives reinforced Capgemini’s technical excellence and innovation capability, delivering consistent results, long-term reliability, and measurable value to the organization and its stakeholders.
Technologies and Skills: Java | Spring | AWS | SQL | Oracle | Docker | Git | GitLab | React | HTML | CSS | REST API | Scrum

JavaSpringAWSSQLOracleDocker+7

Jd digital tecnologia

Senior Full-Stack Developer | Technical Lead

Feb 2018 – Feb 2023 · 5 yrs · Guaíba, Rio Grande do Sul, Brazil · On-site

Worked on innovative software solutions for startups and digital transformation initiatives in Brazil and Portugal, applying modern technologies, cloud architecture, and agile methodologies to deliver scalable products.
A major achievement was the development of SmartTour, an AI-driven platform recognized by the World Health Organization as one of the Top 10 Global Innovation Solution for COVID-19 tracking during the pandemic.
The platform combined React, Node.js, and AWS cloud infrastructure orchestrated with Kubernetes and Docker to create a highly scalable and secure environment.
It utilized Artificial Intelligence (AI), behavioral personas, and an expert system to analyze movement patterns and provide predictive insights for smart-city health management.
After the pandemic, SmartTour evolved into “Consensus”, an advanced AI multi-agent system applied in the tourism and smart-city sectors. Consensus enables multiple AI agents to collaborate autonomously, generating optimized recommendations and forecasts for tourism dynamics and city development.
Additionally, I designed and implemented complete enterprise and web platforms from scratch — from architecture and database design to frontend and backend development — using Java (Spring Boot, Java EE, JPA, Hibernate) combined with React.js, Node.js, and React Native.
Delivered secure REST APIs integrating Oracle and MySQL databases, and implemented cloud-native deployments on AWS with Docker and Kubernetes, supported by CI/CD pipelines for continuous delivery.
Collaborated with multidisciplinary teams and mentored developers, promoting clean code, modular design, and agile best practices in fast-paced startup environments.
Tecnologies: Java EE | Spring | JPA | Hibernate | React | Node.js | React Native | Oracle | MySQL | REST | AWS | Docker | Linux | Artificial Intelligence

Java EESpringJPAHibernateReactNode.js+9

Trace sistemas

Software Development Coordinator (Java/PLSQL)

Aug 2007 – Feb 2019 · 11 yrs 6 mos · Porto Alegre, Rio Grande do Sul, Brazil · On-site

Led the design and development of multiple enterprise software platforms from the ground up, focused on workflow automation, help desk management, and agile project governance.
Created a complete suite of management tools between 2009 and 2013, including:
A work planning and team allocation system for project and resource scheduling.
An Agile project management platform with Kanban boards, Burn Down charts, and team dashboards.
A high-performance project scheduling tool, similar to Microsoft Project, with strong emphasis on usability and performance.
Collaborative Canvas and Business Model Canvas applications for strategic planning.
Provided technical leadership and system architecture direction, coordinating the development team and establishing best practices in software engineering, version control, and code quality.
Designed and implemented large-scale enterprise applications using Java EE, JSF, PrimeFaces, Struts, Hibernate, AJAX, ExtJS, HTML5, JavaScript, and Oracle Database.
Collaborated closely with stakeholders to align software architecture with business goals, governance requirements, and agile delivery standards.
Core Technologies:
Java EE · Spring · JSF · PrimeFaces · Struts · Hibernate · Oracle PL/SQL · AJAX · ExtJS · HTML5 · JavaScript · Linux

Java EESpringJSFPrimeFacesStrutsHibernate+7

Totalbanco (now part of totvs financial systems division)

Software Factory Coordinator / Senior Java Developer

Jan 1999 – Sep 2007 · 8 yrs 8 mos · Porto Alegre, Rio Grande do Sul, Brazil · On-site

Led the Software Factory for financial systems development, overseeing Java-based solutions for major banking and credit institutions.
Designed and developed enterprise financial applications, including systems for credit analysis, loan management, internet banking, and card operations.
Developed integration modules between Java and PowerBuilder (2001), enabling interoperability across legacy and modern systems.
Delivered the “Commercial Credit Note” platform for Banco John Deere (2002), streamlining credit operations and automation workflows.
Created in-house Java development frameworks (2003) and provided technical guidance and mentorship to the Software Factory team.
Promoted to Software Factory Coordinator (2005), managing the entire Java development division, ensuring high-quality delivery and adherence to financial compliance standards.
Served as Project Manager for the Unicred North-Northeast Credit System (2006), leading a large-scale project for credit and cooperative management.
Specialized in financial software architecture, integration with banking systems, and performance optimization for high-volume transactions.
Core Technologies:
Java EE · PowerBuilder · JSP · Servlets · JDBC · Oracle · PL/SQL · Financial Systems · Internet Banking · Credit Management