At Transdata, I build and maintain Flutter and Android applications for POS systems and public transport validators used across more than 400 cities in South America.
I re-engineered NFC communication through Kotlin Method Channels, reducing validation latency by 75% from 12.5 seconds to 3.1 seconds. I also patched critical payment handshake vulnerabilities that prevented an estimated R$300K in potential fraud losses.
I architected an offline-first Flutter/BLoC ABT digital wallet with Pix and Apple Pay/Google Pay integrations, scaling it to more than 10 major cities. My work includes payment integrations, Mifare/NFC operations, Pix webhooks, WebSocket communication, automated testing, and Azure DevOps CI/CD pipelines.
Previously at Blueintra, I developed a Flutter app for spare-parts cataloging, quizzes, and rewards. I led a Clean Architecture refactor that reduced feature delivery and bug-resolution time by approximately 50%.
