Senior .NET Engineer (C# Full Stack)

**Job Title: Senior .NET Engineer (C\# Full Stack)** **Location: Remote / Brazil** **Duration: 3\+ Months** **Role Overview** As a Senior .NET Engineer, you will analyze complex technical challenges, decompose them into manageable components, and design scalable, maintainable solutions. You will play a key role in building robust backend systems while collaborating closely with cross\-functional teams to deliver high\-quality, customer\-centric features. **Key Responsibilities** * Analyze complex business and technical problems, design clean architectures, and implement core frameworks. * Design, develop, and maintain RESTful APIs and backend services using C\#, .NET Core, Web API, and Entity Framework. * Apply software architecture principles such as Domain\-Driven Design (DDD) and CQRS to create modular and scalable applications. * Design and manage SQL Server databases, including writing optimized queries, stored procedures, indexing, and performance tuning. * Use Entity Framework (EF Core or EF6\) for efficient ORM\-based data access. * Write clean, well\-documented, testable, and maintainable code following best practices. * Take end\-to\-end ownership of code quality by performing unit, integration, and performance testing in a Shift\-Left / No\-QA environment. * Collaborate with product managers and cross\-functional teams to gather requirements and deliver business\-focused solutions. * Leverage AI\-powered development tools (mandatory), such as GitHub Copilot, Claude, or similar, to improve productivity, code quality, and documentation. **Required Experience \& Skills** * 5\+ years of experience in enterprise or SaaS application development. * Strong hands\-on expertise in: + C\#, .NET Core, and Web API + Angular or other modern frontend frameworks + Entity Framework (EF Core or EF6\) + SQL Server, including query writing, stored procedures, indexing, and performance optimization