Desenvolvedor Fullstack SR (C# / React)

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Desenvolvedor Fullstack SR (C# / React) based in Brazil. As a Senior Fullstack Developer, you will build and evolve scalable digital solutions using C#/.NET on the backend and React on the frontend. You will contribute across the full software lifecycle, from API and interface development to data modeling, testing, security, observability, and performance. The role offers the opportunity to work on sophisticated SaaS solutions where reliability, maintainability, and user experience are critical. You will collaborate closely with Product, QA, UX, and engineering teams in an agile environment. Your technical judgment and ownership will help establish strong engineering practices and accelerate continuous delivery. You will also have the opportunity to apply artificial intelligence, automation, and modern developer tooling to improve software development and engineering productivity.