Matheus de Almeida Piffer

Multi-tenant student information portal serving higher education institutions across Admissions, Registration, Billing, Financial Aid, Housing, and Academics — modernizing legacy ASP Classic applications.

Architecture & Scale

• Designed modular architecture with 31 feature modules serving 3 portal types (student, faculty, applicant)
• Built server-first approach using Next.js 15 App Router + React 19 Server Components
• Implemented 45+ reusable shadcn/ui components with Radix UI primitives

Authentication & Multi-Tenancy

• Built RBAC system supporting 5 roles (student, faculty, applicant, admin, support)
• Implemented middleware with real-time JWT validation and session corruption recovery
• Created tenant-aware configuration for institutional customization

Accessibility & i18n

• Achieved WCAG 2.2 AA compliance with automated axe-core testing in Playwright
• Implemented full i18n support for 4 languages (EN, PT, ES, FR) with namespace

Led architecture and development of a multi-tenant SaaS platform for field sales and promoter management serving retail networks. Full technical ownership from system design to production deployment.

Architecture & Scale

• Architected 100k+ lines of TypeScript across 32 domain modules using DDD and clean architecture
• Designed single-database multi-tenant system with complete tenant isolation
• Implemented repository pattern, use cases, and presenter layers for maintainability

AI & Machine Learning Features

• Developed production-ready WhatsApp AI chatbot (V2) with 100% test coverage
• Implemented RAG system for document Q&A with semantic search (Azure AI Search)
• Built 3-tier intent classification: Pattern → Semantic → LLM cascade
• Integrated Azure OpenAI (GPT-4o), AWS Bedrock, and embedding models

Real-Time & Async Processing

• Designed queue-based architecture with BullMQ handling 5s webhook constraintsBuilt 3-tier memory system for conversational context preservation
• Created bulk import pipelines for CSV/Excel processing at scale

High-traffic supermarket e-commerce platform with multiple sales channels.

Designed and developed backend services using NestJS with async processing via BullMQ, supporting scalable order and integration workflows.

Led the migration of critical integrations from Magento to VTEX, improving system scalability and reliability.

Built and maintained an internal admin panel using Next.js, integrated with Azure Blob Storage for asset management.

Developed Backend-for-Frontend (BFF) services to synchronize data across client-facing applications and third-party systems.

Managed database operations including schema design, query optimization, and data migrations.

Implemented unit, integration, and end-to-end (E2E) tests using Jest to ensure system stability and maintainability.

Worked closely with product and business stakeholders to translate requirements into technical solutions, while maintaining high code quality through reviews and documentation.