[Job - 31359]Sr. Developer FullStack (.Net/React) , Brazil

At CI&T, we help large enterprises transform the potential of AI into real business impact with AI Deployment, AI-native execution, and tech-integrated business solutions. With 30 years of experience in technological transformation, we accelerate innovation with expertise in Agentic SDLC, Application modernization, Data & AI, Martech and Business strategy. We are 8,000 CI&Ters across more than 25 countries, collaborating to build solutions with real impact. AI is already part of how we work, evolve, and innovate every day. We are looking for a Fullstack Developer with a strong focus on frontend development (70%) and solid backend skills (30%) , working in a modern tech stack built on .NET 8, C# , and React . You will build high-quality, scalable, and maintainable features across the full stack, collaborating closely with product, design, and engineering teams. Requisitos: Develop and maintain responsive, performant, and accessible user interfaces using React Implement reusable components following best practices for scalability and maintainability Collaborate with UX/UI designers to translate designs into functional features Ensure cross-browser compatibility and performance optimization Write unit and integration tests for frontend components Develop and maintain RESTful APIs and services using .NET 8 and C# Implement business logic using the Mediator pattern (MediatR) for clean and decoupled architecture Use AutoMapper for efficient object-to-object mapping Implement asynchronous messaging with Rebus and Azure Service Bus Contribute to database design and queries using PostgreSQL and MongoDB Write unit tests using xUnit and generate realistic test data with Faker (Bogus) Create test doubles and mocks using NSubstitute Participate in code reviews to uphold code quality standards Work with Azure DevOps for project management, version control, and pipelines Follow GitFlow branching strategy for organized and release-oriented development Contribute to Azure Pipelines (CI/CD) using YAML-based configurations Solid experience with React (hooks, context, state management) Proficiency in JavaScript / TypeScript Experience with component-driven development and modern frontend architecture patterns Experience with .NET 8 and C# for backend development Familiarity with MediatR, AutoMapper , and clean architecture principles Experience with messaging/queueing systems (Rebus, Azure Service Bus, or equivalent) Experience with PostgreSQL — relational modeling and query optimization Experience with MongoDB — document-based modeling and aggregation Proficiency with Entity Framework Core (EF Core) xUnit for unit and integration testing NSubstitute for mocking and test doubles Faker / Bogus for realistic test data generation Azure DevOps, Git, GitFlow, Azure Pipelines, Azure Service Bus Diferenciais: Knowledge of CQRS combined with MediatR Familiarity with Docker and containerization Exposure to Azure cloud services (App Services, Functions) Understanding of Domain-Driven Design (DDD) principles Experience with micro-frontend architecture #LI-AM2 Our benefits: -Health and dental insurance -Meal and food allowance -Childcare assistance -Extended paternity leave -Partnership with gyms and health and wellness professionals via Wellhub (Gympass) TotalPass; - Profit Sharing and Results Participation (PLR); -Life insurance - Continuous learning platform (CI&T University); -Discount club -Free online platform dedicated to physical, mental, and overall well-being -Pregnancy and responsible parenting course -Partnerships with online learning platforms -Language learning platform And many more! More details about our benefits here: https://ciandt.com/br/pt-br/carreiras At CI&T, inclusion starts at the first contact. If you are a person with a disability, it is important to present your assessment during the selection process. See which data needs to be included in the report by clicking here . This way, we can ensure the support and accommodations that you deserve. If you do not yet have the assessment, don't worry: we can support you in obtaining it. We have a dedicated Health and Well-being team, inclusion specialists, and affinity groups who will be with you at every stage. Count on us to make this journey side by side.