Open to opportunities

Carlos Mendoza

@carlosmendoza

Message

I build reliable backend systems for fintech, healthcare, and e-commerce using Java, Kafka, and cloud infrastructure.

Brazil

Message

What I'm looking for

I'm seeking a mid-level to senior backend role where I can build scalable production systems and grow into system design leadership.

I've built production backend systems at PicPay, supporting payment processing, fraud detection, and settlement workflows handling 500K+ daily transactions. I implemented event-driven microservices with Apache Kafka, Java/Spring Boot BFF services, and secure PHP/Laravel authentication APIs.

I work closely with technical leaders to turn architectural patterns into scalable code, contributing to decisions around Kafka, MongoDB partitioning, observability, and API design. Using New Relic and OpenSearch, I helped reduce mean time to detection from hours to minutes and protected customer-facing payment flows.

Previously at Mobile Saúde, I developed healthcare APIs, provider dashboards, AWS deployments, and third-party integrations for patient-care workflows. I also built frontend experiences in Vue.js and worked with MySQL, PHP, and secure cloud infrastructure.

Earlier, at ALERTRACK SOLUÇÕES, I delivered web scraping automation, REST APIs, real-time communication features, shipment tracking integrations, push notifications, and automated testing. I'm growing toward system design leadership while continuing to build dependable services across Java, Spring, Kafka, PHP, and AWS.

Experience

Work history, roles, and key accomplishments

Back End Developer

PicPay

Aug 2021 - Jun 2026 (4 years 10 months)

- Implemented event-driven microservices architecture using Apache Kafka under technical leadership, optimizing message routing and consumer groups for 500K+ daily transactions between payment processing, fraud detection, and settlement services. Ensured reliable delivery of critical financial data using TDD methodology (JUnit), achieving zero critical bugs in payment handling.

- Developed Backe

PHP Laravel Kafka Java MongoDB OpenAPI Spring Framework

Full Stack Engineer

Mobile Saúde

Dec 2018 - Aug 2021 (2 years 8 months)

- Developed and maintained healthcare APIs and backend services in PHP with Bitbucket version control and MySQL, implementing patient data workflows designed by product team. Healthcare work required meticulous attention to data integrity and HIPAA compliance.

- Built responsive frontend interfaces using Vue.js, creating dashboards for healthcare providers to access patient records and manage ap

PHP Web Application Development HTML CSS CodeIgniter API Development MySQL JavaScript Vue.Js

Full Stack Engineer

ALERTRACK SOLUÇÕES

Aug 2017 - Dec 2018 (1 year 4 months)

- Developed web scraping automation using Node.js and Selenium, extracting real-time e-commerce and logistics data. Automated data collection eliminated manual entry errors and enabled real-time inventory tracking for e-commerce customers.

- Built real-time communication features using WebRTC, enabling customer service teams to respond to customer inquiries instantly. Real-time chat reduced supp