Barbara Sousa

Architecting and delivering two production-grade Next.js applications for a blockchain SaaS platform serving a global leader in testing, inspection, and certification. Implemented distributed locking mechanisms with Node.js and PostgreSQL to ensure data consistency across cross-service transactions in mission-critical certification workflows. Designed a shared component library in a monorepo that reduced code duplication by 50% and accelerated feature delivery by approximately 40%. Working closely with backend and product teams to translate complex blockchain business logic into scalable, maintainable interfaces using React, Next.js, NestJS, and Tailwind CSS. I work closely with cross-functional teams to transform complex business logic into intuitive, scalable interfaces. I also collaborate on integrating the frontend with our NestJS backend and contribute to UI architecture decisions that support long-term growth and usability. At Multiledgers, I’ve been part of a fast-paced and innovation-driven environment, helping to deliver tech solutions that empower businesses in sustainability and infrastructure management.

Led the full mobile-first rebuild of the Metrópoles app for one of Latin America's largest digital news portals, reaching 50M+ monthly unique visitors. The refactored version shipped to production and tripled the active user base, growing it to approximately 200k users. Achieved Lighthouse scores of 100 on critical pages and reduced accessibility violations by 95% (WCAG AAA). Implemented interest-based push notifications using Firebase, improving user retention and content consumption. Used Sentry to monitor system health and reduce production incidents. Mentored 3 engineers and introduced CircleCI pipelines with Cypress E2E tests to catch regressions before production.

Developed web and mobile applications for Grupo Pão de Açúcar, one of LATAM's largest retail chains. Engineered high-concurrency Java backend services and React Native checkout flows that handled 100k+ concurrent sessions during Black Friday peaks with 99.9% availability, contributing to a 20% increase in mobile conversion rates. The app surpassed 7.5M downloads, with approximately 67% of in-store smartphone users opening it regularly to activate offers. Stack: React, React Native, Redux, Java, TypeScript.

Led the development of a Flutter application for an auto-enrollment pension startup based in London, UK. Responsible for designing and building the mobile system from scratch, while also contributing to the web application using React and TypeScript.

Built web and mobile applications for government projects using React, Redux, and React Native. Developed end-to-end test suites with Cypress across multiple applications, improving reliability and reducing regression risk in critical public sector systems.

As a Front-End Software Engineer at the Department of Scientific and Technical of the Federal Police, I played a pivotal role in the technological advancement of their systems. Initially working with vanilla JavaScript and jQuery, I contributed to the migration of systems to utilize Vue.js. This transition aimed at enhancing the efficiency and functionality of critical systems within the Federal Police, showcasing my adaptability and proficiency in modern front-end technologies.

Formação técnica