Matheus – React, Typescript, .NET

It's self-checkout systems for multiple convenience brands across Europe.

• Implemented the MVP React application and central state management.
• Built the promotion engine library in .NET.
• Architected a central payment system for all stores.
• Wrote integration and end-to-end tests.
• Optimized database queries for better performance.
• Automated infrastructure provisioning and deployment with Terraform.
• Mentored and onboarded 5+ developers to the project.
• Coordinated with internal and external teams, including security and auditors, to ensure compliance for self-checkout systems.

It's a secure messaging layer that enables Swiss organizations to exchange sensitive data reliably and in a structured way. It provides API and webhook-based integration for seamless message delivery, processing, and auditing across systems.

• Designed and implemented a secure messaging architecture for the Swiss company network.
• Built API- and webhook-based communication flows for reliable message exchange.
• Developed Blazor SSR pages to administer message delivery.
• Implemented event sourcing for full auditability and traceability.
• Built resilient message processing with retry, queuing, and failure handling.
• Designed and optimized PostgreSQL data models for sensitive, high-integrity data.
• Applied end-to-end security practices for confidential information handling.
• Automated deployment pipelines to a private Kubernetes cluster.
• Designed CI/CD workflows for versioning, rollout, and rollback.
• Containerized services and managed Kubernetes orchestration.
• Implemented logging, monitoring, and observability for distributed message flows.

It's an open-source multi-currency budgeting and finance tracker, designed to help users manage budgets, expenses, and assets.

• Implemented multi-currency financial models and calculations.
• Built a scalable full-stack architecture with Next.js, Drizzle ORM, and PostgreSQL.
• Developed dynamic reporting and expense visualization features.
• Maintained code quality, testing, and open-source documentation.

It's a secure document exchange platform that enables structured, compliant communication between institutions, allowing them to efficiently request information and share updates related to insured individuals and companies.

• Designed and implemented a full system architecture covering front-end, back-end, and infrastructure.
• Modeled and optimized database schema for structured document exchange.
• Built scalable APIs and core business logic for inter-agency workflows.
• Developed modular, reusable frontend component system.
• Implemented advanced search and filtering across documents and entities.
• Automated infrastructure provisioning and deployment with Terraform.
• Ensured compliance with D-SIPD standards and secure data exchange protocols.
• Implemented end-to-end testing strategy (unit, integration, and e2e).
• Optimized performance, reliability, and system observability.
• Led debugging, issue resolution, and ongoing system improvements.

It's a digital receipt platform that allows customers to receive receipts instantly via QR codes.

• Designed and implemented an end-to-end workflow for digital receipt delivery.
• Built a secure QR-code system linking transactions to individual customers.
• Implemented real-time receipt delivery via server-sent events.
• Developed a fast, resilient back-end for transaction feeds and user requests.
• Created front-end pages for instant receipt viewing and safe reloads.
• Ensured transaction integrity and accurate QR-to-receipt mapping.
• Integrated with the company's point-of-sale systems for seamless rollout.
• Added logging, monitoring, and error handling for reliable delivery.