Senior Back-end Developer (.NET)

8+ years of professional experience in backend development with .NET / C#Proven hands-on work with .NET Core / .NET 8+ (not primarily .NET Framework legacy maintenance)Proven production experience with Clean Architecture and CQRS patterns (MediatR or similar)Strong MySQL expertise with Dapper for high-performance queries and EF Core for domain managementHands-on AWS experience: Fargate, RDSDemonstrated focus on unit and integration testingC1 English level or higherExperience migrating large legacy systems incrementally without breaking existing behaviorActive use of AI tools (Claude Code, GitHub Copilot, or similar) integrated into the daily development workflowBonus: experience building or configuring MCP servers, multi-agent workflows, or custom AI integrationsSkills.NET 8+C#Clean ArchitectureCQRSMediatRMySQLDapperEF CoreAWS FargateAWS RDSUnit TestingIntegration Testing Migrate complex legacy business logic to modern .NET 8+ Web APIs following Clean Architecture principles (Domain, Application, Infrastructure)Design and implement secure, robust APIs with strict authentication flows and compliance-mandated session timeoutsOptimize MySQL data access: Dapper for performance-critical paths, EF Core for standard domain operationsDefine clear API contracts for frontend integration and payment provider connectivity (Braintree/Paymentech) You will lead the migration of a legacy system to a modern .NET 8+ backend under Clean Architecture. Working in a high-availability environment with complex business rules and strict security regulations, you will translate legacy logic into robust Web APIs, optimize MySQL data access, and implement secure authentication flows. Your work directly enables reliable integration with payment providers and frontend systems in a regulated domain where technical precision is critical. We provide the opportunity to participate in impactful and technically rigorous industrial data projects that drive innovation and professional growth. Our work environment emphasizes technical excellence, collaboration, and continuous innovation.Niuro supports a 100% remote work model, allowing flexibility in work location globally. We invest in career development through ongoing training programs and leadership opportunities, ensuring continuous growth and success.Upon successful completion of the initial contract, there is potential for long-term collaboration and stable, full-time employment, reflecting our long-term commitment to our team members.Joining Niuro means becoming part of a global community dedicated to technological excellence and benefiting from a strong administrative support infrastructure that enables you to focus on impactful work without distraction.