12+ years building enterprise-grade software with .NET and modern cloud technologies. Specializing in Fintech, clean architecture, and systems that scale.
const developer = {
name: "Jonathan Peris",
role: "Software Engineer",
location: "Itanhaém, Brazil",
experience: "12+ years",
focus: [".NET", "Fintech", "Cloud"],
languages: ["C#", "Rust", "Go", "Python"],
available: true,
};I specialize in .NET and Fintech — currently building core financial modules for a capital markets platform at Derivative Path.
My work spans .NET Core+, ASP.NET Core, Entity Framework, and MAUI. I design systems with CQRS, DDD, Microservices, Hexagonal Architecture, and Cloud-Native principles — always building for durability.
I've delivered across financial services, automotive (Mercedes-Benz/T-Systems), EdTech, healthcare, retail, and insurance. Strong DevOps background with Azure, Docker, and CI/CD.
Beyond .NET, I explore Rust, Go, and Python — driven by curiosity about performance, concurrency, and the next generation of systems.
Software Engineer on the CAAR team, focused on developing and refining the General Ledger, Hedge Accounting, and Fiscal Calendar modules for the DerivativeEDGE platform. Enabling clients to achieve streamlined financial reporting, accurate hedge accounting, and efficient fiscal period management.
Spearheaded the critical platform and architecture migration of SGP Eletrônica — vital software for mapping and parameterization of Electronic Control Units (ECUs) within Mercedes-Benz trucks and buses. Ensured seamless transition while modernizing architecture and enhancing capabilities for advanced automotive diagnostics.
Drove full-cycle development of the ExamReview platform — backend services, infrastructure, and mobile. Engineered the CMS delivering educational materials to thousands of students via LMS. Built the Admin platform for access control and hierarchy structuring. All platforms on Azure with Microservices, CQRS, and full test coverage.
Ensured reliability of international wire transfers within XP Inc.'s international accounts group. Maintained and enhanced monitoring processes for Brazil-US fund transfers, managing Azure infrastructure and .NET Core microservices leveraging SAGA patterns and message queues for transactional consistency.
Led design and development of key internal applications in Agile/Scrum. Engineered T-Atendo (helpdesk for Mercedes-Benz factory workers), Multi Manager (resource booking for on-site assets), and T-Entrego (corporate gift distribution platform). All built with .NET Core, Azure, and microservices.
Built specialized applications for factory operations and corporate functions. Developed mileage control systems for Mercedes-Benz trucks and maintained institutional and intranet applications for internal communication and processes.
Developed hospital internal control applications and proof of concept projects. 5A Attiva maintains all internal Amil clinical systems in hospitals and clinics across Brazil.
Developed the second version of the label generation system for all Leroy Merlin stores and expanded the business operations management system. SONDA is a leader in systems integration and IT services in Latin America.
Developed insurance sales applications for major insurers including Zurich, Assurant, Mapfre, and Cardiff. Built integration with SIGEP WEB (Post Office) for ticket issuance and object returns.
Technical support for the state water supply and sanitation company. Configured Active Directory, virtual machines, LDAP, and managed backup contingency. Participated in development of the company's process system.
A full-featured .NET sample application showcasing clean architecture, dependency injection, comprehensive testing, and Docker containerization. Built as a real-world reference for modern .NET development practices with a complete web client.
A classic side-scrolling platformer built from scratch with C and SDL2. Compiled to WebAssembly so it runs directly in the browser — no install needed. Features sprite animation, collision detection, and retro-style gameplay.
My entry for the Rinha de Backend 2024/Q1 challenge — a high-performance concurrency-focused API built in C# with PostgreSQL and Nginx. Designed to handle extreme load under strict resource constraints (1.5 CPU / 550MB RAM).
Load testing suite for the Rinha de Backend 2024/Q1 challenge using Grafana K6. Simulates realistic concurrent traffic patterns to stress-test API endpoints and validate correctness under heavy load.