Jonatas S. O. Vieira

Senior Software Engineer

Campinas, BR.

About

Highly accomplished Senior Software Engineer with over 9 years of experience in designing, developing, and optimizing complex distributed systems and data processing platforms. Specializes in leveraging Java, Python, and cloud-native technologies (AWS, Kubernetes, Kafka) to build scalable microservices architectures and deliver high-impact solutions for diverse industries, including finance, logistics, and telecommunications.

Work

Kohls US

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Java Software Engineer

Menomonee Falls, Wiscounsin, United States

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Contract

Summary

Help the team design, develop, and maintain the pricing engine platform responsible for calculating product prices, discounts, and promotional rules at scale. Support and enhance the legacy system while simultaneously contributing to the development of a new modernized platform based on Spring Boot and Kotlin. Apply clean architecture and strong object-oriented design principles, focusing on high reusability, maintainability, modularization, and testability through small, well-defined methods and components. Follow modern development practices such as SOLID principles, domain-driven design concepts, and automated testing strategies. Work with feature flags to safely release and validate new functionalities in production environments. Use GitLab CI for continuous integration and deployment pipelines, and OpenShift as the container orchestration platform for deploying and managing microservices. The ecosystem includes Java 17 legacy applications currently being migrated to Java 25 and modern Kotlin-based services. The technology stack also includes Maven for dependency management and build automation, IntelliJ IDEA as the primary development environment, and MySQL as the relational database solution.

Sysmap Solutions

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Software/Data Engineer

Brazil, Brazil

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Summary

Leading the development of a robust data processing platform, specializing in data preparation and leveraging advanced distributed systems.

Highlights

Architected and implemented a scalable data processing platform using Java, Python, Apache Kafka, and Kafka Streams to handle high-volume data preparation.

Integrated Open Telemetry and Spring Sleuth for comprehensive distributed tracing and observability across microservices, improving system diagnostics and performance monitoring.

Utilized Docker and Kubernetes for efficient container orchestration and deployment, ensuring high availability and seamless scaling of critical data infrastructure.

Implemented robust monitoring and logging solutions with Grafana and the ELK stack (Elasticsearch, Logstash, Kibana) to provide real-time insights into platform health and operational metrics.

Olist Digital Services

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Software Engineer

Brazil, , Brazil

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Summary

Developed and deployed a critical API for freight hiring and label generation, integrating with diverse carrier partners to streamline logistics operations.

Highlights

Designed and implemented a comprehensive API, developed with Java and Python, to manage end-to-end freight hiring processes and generate shipping labels for multiple carrier partners.

Leveraged AWS EKS, SNS, and SQS to build a highly available and scalable microservices architecture, ensuring robust communication and efficient message queuing.

Utilized Spring Boot and Spring Data with PostgreSQL for efficient data management and persistence, optimizing API performance and data integrity.

Integrated JasperReports for dynamic label generation and ZPL for printer compatibility, enhancing operational efficiency and accuracy in logistics processes.

Managed containerized deployments with Docker and Kubernetes, and optimized data caching with Redis for improved API response times and user experience.

Zup Innovation

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Software Engineer

Brazil, , Brazil

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Summary

Engineered microservices solutions for major Brazilian banks, significantly reducing operational costs and modernizing legacy mainframe systems.

Highlights

Contributed to a project that enabled Brazilian banks to achieve R$2 billion in savings by successfully re-architecting mainframe-based services into a modern microservices architecture.

Developed high-performance microservices using Java and Python with Spring Boot, enhancing system agility, scalability, and maintainability.

Migrated critical banking functionalities from legacy mainframes to a cloud-native environment, leveraging Docker, Kubernetes, and AWS Fargate for robust deployment.

Implemented resilient data persistence layers with SQL Server and Spring Data, ensuring high data integrity and efficient transaction processing for financial applications.

Integrated RabbitMQ for asynchronous messaging, improving inter-service communication and overall system resilience within the banking infrastructure.

Logicalis

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Software Engineer

Brazil, , Brazil

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Summary

Developed robust systems for Brazilian telecommunications companies to track and analyze mobile IP address data, managing high-volume logs and data for critical insights.

Highlights

Designed and implemented a data tracking system for Brazilian telco companies, monitoring the entire range of mobile IP addresses assigned to customers.

Processed and managed a massive volume of daily logs and IP change data, enabling comprehensive historical analysis and real-time querying capabilities.

Utilized Java, Groovy, and Python with Spring Boot to build scalable backend services for data ingestion and processing.

Implemented data pipeline automation with Apache NiFi and integrated monitoring tools like Mmonit, NetSNMP, Grafana, and Riemann.io for comprehensive system health oversight.

Deployed solutions using Docker and Kubernetes, ensuring efficient resource management and high availability for critical data services.

Managed authentication and authorization with FreeRadius and Keycloak, and facilitated high-speed data search and analysis with Elasticsearch.

Synchro Tax Solutions

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Software Engineer

Brazil, , Brazil

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Summary

Developed and maintained internal systems crucial for supporting the company's entire tax operation, providing essential tools across all departments.

Highlights

Engineered and enhanced internal enterprise systems using Java, Spring Boot, and Python to optimize operational workflows across various departments.

Developed user interfaces with ReactJS and JSF, significantly improving the usability and efficiency of internal tools for diverse business functions.

Implemented advanced search functionalities and data indexing with SOLR, enabling quick and accurate access to critical tax-related information.

Contributed to the full software development lifecycle, from requirements gathering to deployment, ensuring the delivery of robust and reliable internal applications.

Education

Federal Institute of Education, Science and Technology of Sao Paulo, SP-Campinas

Campinas, SP, Brazil
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Technologist Degree Systems Analysis and Development

Courses

Tutor of PL3 (Programming Language 3)

Awards

Highest Academic Achievement (High School)

School Performance Assessment of Sao Paulo

Recognized for achieving the highest grade in class during the school performance assessment of Sao Paulo at the high school level, demonstrating early academic excellence.

Languages

Portuguese

English

Skills

Programming Languages

Java, Python, JavaScript, Groovy.

Frameworks & Libraries

Spring Boot, Spring Data, ReactJS, JSF.

Data Technologies

Apache Kafka, Kafka Streams, PostgreSQL, OracleDB, SQL Server, Elasticsearch, Redis, SOLR, Apache NiFi, RabbitMQ.

Cloud & DevOps

AWS (EKS, SNS, SQS, Fargate), Docker, Kubernetes, Open Telemetry, Spring Sleuth, Grafana, ELK Stack, Unix, GIT, Ansible.

Methodologies & Tools

Scrum, Microservices Architecture, Distributed Systems, API Development, Data Pipelines, System Design, Monitoring, Observability, JasperReports, ZPL.

Security & Authentication

FreeRadius, Keycloak.