Portfolio

Led the design and build of a single sign-on system with biometric authentication, replacing per-system logins for healthcare staff in a mission-critical environment.

• Designed an SSO system with JWT, password encryption, and biometric authentication (fingerprint and facial recognition), integrated with more than 5 internal systems.
• Reduced healthcare staff access time by ~80% by eliminating individual logins per system.
• Reverse-engineered an undocumented 800-line legacy biometric engine, mapping its WebSocket integration and undocumented API endpoints to enable a new .NET implementation with CQRS.
• Rebuilt the biometric authentication UI in React, replacing the legacy JavaForms screen and adding retry logic, error/success states, and the first documented Swagger spec for the flow.

Built and maintained hospital management modules — clinical protocols, prescriptions, vital signs, bed and equipment management — for a system serving over 69,000 staff and 15.7 million patients.

• Optimized a critical prescription scheduling screen, cutting rendering time from 1.5s to 180ms via list virtualization, server-side pagination, and React memoization (useCallback, useMemo, memo).
• Worked across heterogeneous production databases (SQL Server for the auth module, Oracle for the legacy core), including data sync between the two.
• Created frontend architecture patterns adopted by the team — API notification middleware, routing conventions, and factories for recurring actions — reducing rework across the squad.
• Contributed to strategic architecture decisions: adopting Clean Architecture and CQRS in the .NET APIs and migrating the backend from Django to .NET 7.

Led the migration of GESCON, a legacy VB.NET municipal management system, to Angular and .NET 5, keeping the old system live and operational throughout the transition.

• Migrated a legacy VB.NET system to Angular + .NET 5 with zero downtime, running both systems in parallel during the cutover.
• Proposed and led the adoption of Clean Architecture: presented the plan to the team, drove a 1-month refactor, removed ~900 lines of dead code, and introduced automated tests.
• Found a sensitive data leak in the GESCON API, reported it, and shipped a fix that reduced data exposure to the minimum necessary.
• Applied file streaming to high-volume processing, cutting report generation time from 2s to 300ms and overall load time by 3s.

Built a data-privacy compliance platform with JWT authentication, role-based access control, and audit trails to meet LGPD (Brazil's data protection law) requirements across multiple client systems.

• Designed a platform with JWT auth, RBAC, audit trails, and encryption for sensitive data, giving the client traceability and legal compliance across systems.
• Delivered ASP.NET MVC and Razor Pages applications in C# with Entity Framework and SQL Server, focused on query optimization and high-volume reporting.
• Integrated REST APIs with legacy systems to consolidate data that previously lived in isolated platforms.